🎨 Fewer serial macros

Marlin/src/HAL/AVR/fastio.cpp

     SET_WGM(5, FAST_PWM_ICRn);            // Fast PWM with ICR5 as TOP
 
     //SERIAL_ECHOLNPGM("Timer 5 Settings:");
-    //SERIAL_ECHOLNPAIR("  Prescaler=", prescaler);
-    //SERIAL_ECHOLNPAIR("        TOP=", ICR5);
-    //SERIAL_ECHOLNPAIR("      OCR5A=", OCR5A);
-    //SERIAL_ECHOLNPAIR("      OCR5B=", OCR5B);
-    //SERIAL_ECHOLNPAIR("      OCR5C=", OCR5C);
+    //SERIAL_ECHOLNPGM("  Prescaler=", prescaler);
+    //SERIAL_ECHOLNPGM("        TOP=", ICR5);
+    //SERIAL_ECHOLNPGM("      OCR5A=", OCR5A);
+    //SERIAL_ECHOLNPGM("      OCR5B=", OCR5B);
+    //SERIAL_ECHOLNPGM("      OCR5C=", OCR5C);
   }
   else {
     // Restore the default for Timer 5

Marlin/src/HAL/AVR/pinsDebug.h

 
 inline void com_print(const uint8_t N, const uint8_t Z) {
   const uint8_t *TCCRA = (uint8_t*)TCCR_A(N);
-  SERIAL_ECHOPAIR("    COM", AS_DIGIT(N));
+  SERIAL_ECHOPGM("    COM", AS_DIGIT(N));
   SERIAL_CHAR(Z);
-  SERIAL_ECHOPAIR(": ", int((*TCCRA >> (6 - Z * 2)) & 0x03));
+  SERIAL_ECHOPGM(": ", int((*TCCRA >> (6 - Z * 2)) & 0x03));
 }
 
 void timer_prefix(uint8_t T, char L, uint8_t N) {  // T - timer    L - pwm  N - WGM bit layout
   uint8_t WGM = (((*TCCRB & _BV(WGM_2)) >> 1) | (*TCCRA & (_BV(WGM_0) | _BV(WGM_1))));
   if (N == 4) WGM |= ((*TCCRB & _BV(WGM_3)) >> 1);
 
-  SERIAL_ECHOPAIR("    TIMER", AS_DIGIT(T));
+  SERIAL_ECHOPGM("    TIMER", AS_DIGIT(T));
   SERIAL_CHAR(L);
   SERIAL_ECHO_SP(3);
 
     const uint16_t *OCRVAL16 = (uint16_t*)OCR_VAL(T, L - 'A');
     PWM_PRINT(*OCRVAL16);
   }
-  SERIAL_ECHOPAIR("    WGM: ", WGM);
+  SERIAL_ECHOPGM("    WGM: ", WGM);
   com_print(T,L);
-  SERIAL_ECHOPAIR("    CS: ", (*TCCRB & (_BV(CS_0) | _BV(CS_1) | _BV(CS_2)) ));
-  SERIAL_ECHOPAIR("    TCCR", AS_DIGIT(T), "A: ", *TCCRA);
-  SERIAL_ECHOPAIR("    TCCR", AS_DIGIT(T), "B: ", *TCCRB);
+  SERIAL_ECHOPGM("    CS: ", (*TCCRB & (_BV(CS_0) | _BV(CS_1) | _BV(CS_2)) ));
+  SERIAL_ECHOPGM("    TCCR", AS_DIGIT(T), "A: ", *TCCRA);
+  SERIAL_ECHOPGM("    TCCR", AS_DIGIT(T), "B: ", *TCCRB);
 
   const uint8_t *TMSK = (uint8_t*)TIMSK(T);
-  SERIAL_ECHOPAIR("    TIMSK", AS_DIGIT(T), ": ", *TMSK);
+  SERIAL_ECHOPGM("    TIMSK", AS_DIGIT(T), ": ", *TMSK);
 
   const uint8_t OCIE = L - 'A' + 1;
   if (N == 3) { if (WGM == 0 || WGM == 2 || WGM ==  4 || WGM ==  6) err_is_counter(); }

Marlin/src/HAL/DUE/eeprom_flash.cpp

     pageContents[i] = (((uint32_t*)data)[i]) | (~(pageContents[i] ^ ((uint32_t*)data)[i]));
 
   DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM PageWrite   ", page);
-  DEBUG_ECHOLNPAIR(" in FLASH address ", (uint32_t)addrflash);
-  DEBUG_ECHOLNPAIR(" base address     ", (uint32_t)getFlashStorage(0));
+  DEBUG_ECHOLNPGM("EEPROM PageWrite   ", page);
+  DEBUG_ECHOLNPGM(" in FLASH address ", (uint32_t)addrflash);
+  DEBUG_ECHOLNPGM(" base address     ", (uint32_t)getFlashStorage(0));
   DEBUG_FLUSH();
 
   // Get the page relative to the start of the EFC controller, and the EFC controller to use
     __enable_irq();
 
     DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Unlock failure for page ", page);
+    DEBUG_ECHOLNPGM("EEPROM Unlock failure for page ", page);
     return false;
   }
 
     __enable_irq();
 
     DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Write failure for page ", page);
+    DEBUG_ECHOLNPGM("EEPROM Write failure for page ", page);
 
     return false;
   }
 
     #ifdef EE_EMU_DEBUG
       DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Verify Write failure for page ", page);
+      DEBUG_ECHOLNPGM("EEPROM Verify Write failure for page ", page);
 
       ee_Dump( page, (uint32_t *)addrflash);
       ee_Dump(-page, data);
           }
         }
       }
-      DEBUG_ECHOLNPAIR("--> Differing bits: ", count);
+      DEBUG_ECHOLNPGM("--> Differing bits: ", count);
     #endif
 
     return false;
   uint32_t addrflash = uint32_t(getFlashStorage(page));
 
   DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM PageErase  ", page);
-  DEBUG_ECHOLNPAIR(" in FLASH address ", (uint32_t)addrflash);
-  DEBUG_ECHOLNPAIR(" base address     ", (uint32_t)getFlashStorage(0));
+  DEBUG_ECHOLNPGM("EEPROM PageErase  ", page);
+  DEBUG_ECHOLNPGM(" in FLASH address ", (uint32_t)addrflash);
+  DEBUG_ECHOLNPGM(" base address     ", (uint32_t)getFlashStorage(0));
   DEBUG_FLUSH();
 
   // Get the page relative to the start of the EFC controller, and the EFC controller to use
     __enable_irq();
 
     DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Unlock failure for page ",page);
+    DEBUG_ECHOLNPGM("EEPROM Unlock failure for page ",page);
 
     return false;
   }
     __enable_irq();
 
     DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Erase failure for page ",page);
+    DEBUG_ECHOLNPGM("EEPROM Erase failure for page ",page);
 
     return false;
   }
   for (i = 0; i < PageSize >> 2; i++) {
     if (*aligned_src++ != 0xFFFFFFFF) {
       DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Verify Erase failure for page ",page);
+      DEBUG_ECHOLNPGM("EEPROM Verify Erase failure for page ",page);
       ee_Dump(page, (uint32_t *)addrflash);
       return false;
     }
   if (curGroup >= GroupCount) curGroup = 0;
 
   DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM Current Group: ",curGroup);
+  DEBUG_ECHOLNPGM("EEPROM Current Group: ",curGroup);
   DEBUG_FLUSH();
 
   // Now, validate that all the other group pages are empty
     for (int page = 0; page < PagesPerGroup; page++) {
       if (!ee_IsPageClean(grp * PagesPerGroup + page)) {
         DEBUG_ECHO_START();
-        DEBUG_ECHOLNPAIR("EEPROM Page ", page, " not clean on group ", grp);
+        DEBUG_ECHOLNPGM("EEPROM Page ", page, " not clean on group ", grp);
         DEBUG_FLUSH();
         ee_PageErase(grp * PagesPerGroup + page);
       }
   }
 
   DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM Active page: ", curPage);
+  DEBUG_ECHOLNPGM("EEPROM Active page: ", curPage);
   DEBUG_FLUSH();
 
   // Make sure the pages following the first clean one are also clean
   for (int page = curPage + 1; page < PagesPerGroup; page++) {
     if (!ee_IsPageClean(curGroup * PagesPerGroup + page)) {
       DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Page ", page, " not clean on active group ", curGroup);
+      DEBUG_ECHOLNPGM("EEPROM Page ", page, " not clean on active group ", curGroup);
       DEBUG_FLUSH();
       ee_Dump(curGroup * PagesPerGroup + page, getFlashStorage(curGroup * PagesPerGroup + page));
       ee_PageErase(curGroup * PagesPerGroup + page);

Marlin/src/HAL/DUE/pinsDebug.h

 void pwm_details(int32_t pin) {
   if (pwm_status(pin)) {
     uint32_t chan = g_APinDescription[pin].ulPWMChannel;
-    SERIAL_ECHOPAIR("PWM = ", PWM_INTERFACE->PWM_CH_NUM[chan].PWM_CDTY);
+    SERIAL_ECHOPGM("PWM = ", PWM_INTERFACE->PWM_CH_NUM[chan].PWM_CDTY);
   }
 }
 

Marlin/src/HAL/ESP32/wifi.cpp

 
   MDNS.addService("http", "tcp", 80);
 
-  SERIAL_ECHOLNPAIR("Successfully connected to WiFi with SSID '" WIFI_SSID "', hostname: '" WIFI_HOSTNAME "', IP address: ", WiFi.localIP().toString().c_str());
+  SERIAL_ECHOLNPGM("Successfully connected to WiFi with SSID '" WIFI_SSID "', hostname: '" WIFI_HOSTNAME "', IP address: ", WiFi.localIP().toString().c_str());
 }
 
 #endif // WIFISUPPORT

Marlin/src/HAL/LPC1768/eeprom_sdcard.cpp

   PGM_P const rw_str = write ? PSTR("write") : PSTR("read");
   SERIAL_CHAR(' ');
   SERIAL_ECHOPGM_P(rw_str);
-  SERIAL_ECHOLNPAIR("_data(", pos, ",", value, ",", size, ", ...)");
+  SERIAL_ECHOLNPGM("_data(", pos, ",", value, ",", size, ", ...)");
   if (total) {
     SERIAL_ECHOPGM(" f_");
     SERIAL_ECHOPGM_P(rw_str);
-    SERIAL_ECHOPAIR("()=", s, "\n size=", size, "\n bytes_");
-    SERIAL_ECHOLNPAIR_P(write ? PSTR("written=") : PSTR("read="), total);
+    SERIAL_ECHOPGM("()=", s, "\n size=", size, "\n bytes_");
+    SERIAL_ECHOLNPGM_P(write ? PSTR("written=") : PSTR("read="), total);
   }
   else
-    SERIAL_ECHOLNPAIR(" f_lseek()=", s);
+    SERIAL_ECHOLNPGM(" f_lseek()=", s);
 }
 
 // File function return codes for type FRESULT. This goes away soon, but

Marlin/src/HAL/SAMD51/pinsDebug.h

 void pwm_details(int32_t pin) {
   if (pwm_status(pin)) {
     //uint32_t chan = g_APinDescription[pin].ulPWMChannel TODO when fast pwm is operative;
-    //SERIAL_ECHOPAIR("PWM = ", duty);
+    //SERIAL_ECHOPGM("PWM = ", duty);
   }
 }
 

Marlin/src/HAL/STM32/eeprom_flash.cpp

         // load current settings
         uint8_t *eeprom_data = (uint8_t *)SLOT_ADDRESS(current_slot);
         for (int i = 0; i < MARLIN_EEPROM_SIZE; i++) ram_eeprom[i] = eeprom_data[i];
-        DEBUG_ECHOLNPAIR("EEPROM loaded from slot ", current_slot, ".");
+        DEBUG_ECHOLNPGM("EEPROM loaded from slot ", current_slot, ".");
       }
       eeprom_data_written = false;
     }
         ENABLE_ISRS();
         TERN_(HAS_PAUSE_SERVO_OUTPUT, RESUME_SERVO_OUTPUT());
         if (status != HAL_OK) {
-          DEBUG_ECHOLNPAIR("HAL_FLASHEx_Erase=", status);
-          DEBUG_ECHOLNPAIR("GetError=", HAL_FLASH_GetError());
-          DEBUG_ECHOLNPAIR("SectorError=", SectorError);
+          DEBUG_ECHOLNPGM("HAL_FLASHEx_Erase=", status);
+          DEBUG_ECHOLNPGM("GetError=", HAL_FLASH_GetError());
+          DEBUG_ECHOLNPGM("SectorError=", SectorError);
           LOCK_FLASH();
           return false;
         }
           offset += sizeof(uint32_t);
         }
         else {
-          DEBUG_ECHOLNPAIR("HAL_FLASH_Program=", status);
-          DEBUG_ECHOLNPAIR("GetError=", HAL_FLASH_GetError());
-          DEBUG_ECHOLNPAIR("address=", address);
+          DEBUG_ECHOLNPGM("HAL_FLASH_Program=", status);
+          DEBUG_ECHOLNPGM("GetError=", HAL_FLASH_GetError());
+          DEBUG_ECHOLNPGM("address=", address);
           success = false;
           break;
         }
 
       if (success) {
         eeprom_data_written = false;
-        DEBUG_ECHOLNPAIR("EEPROM saved to slot ", current_slot, ".");
+        DEBUG_ECHOLNPGM("EEPROM saved to slot ", current_slot, ".");
       }
 
       return success;

Marlin/src/HAL/STM32/pinsDebug.h

       if (over_7) pin_number -= 8;
 
       uint8_t alt_func = (alt_all >> (4 * pin_number)) & 0x0F;
-      SERIAL_ECHOPAIR("Alt Function: ", alt_func);
+      SERIAL_ECHOPGM("Alt Function: ", alt_func);
       if (alt_func < 10) SERIAL_CHAR(' ');
       SERIAL_ECHOPGM(" - ");
       switch (alt_func) {

Marlin/src/HAL/STM32/usb_host.cpp

     capacity = info.capacity.block_nbr / 2000;
     block_size = info.capacity.block_size;
     block_count = info.capacity.block_nbr;
-    // SERIAL_ECHOLNPAIR("info.capacity.block_nbr : %ld\n", info.capacity.block_nbr);
-    // SERIAL_ECHOLNPAIR("info.capacity.block_size: %d\n", info.capacity.block_size);
-    // SERIAL_ECHOLNPAIR("capacity                : %d MB\n", capacity);
+    //SERIAL_ECHOLNPGM("info.capacity.block_nbr : %ld\n", info.capacity.block_nbr);
+    //SERIAL_ECHOLNPGM("info.capacity.block_size: %d\n", info.capacity.block_size);
+    //SERIAL_ECHOLNPGM("capacity                : %d MB\n", capacity);
   }
 };
 

Marlin/src/HAL/shared/Delay.cpp

       auto report_call_time = [](PGM_P const name, PGM_P const unit, const uint32_t cycles, const uint32_t total, const bool do_flush=true) {
         SERIAL_ECHOPGM("Calling ");
         SERIAL_ECHOPGM_P(name);
-        SERIAL_ECHOLNPAIR(" for ", cycles);
+        SERIAL_ECHOLNPGM(" for ", cycles);
         SERIAL_ECHOPGM_P(unit);
-        SERIAL_ECHOLNPAIR(" took: ", total);
+        SERIAL_ECHOLNPGM(" took: ", total);
         SERIAL_ECHOPGM_P(unit);
         if (do_flush) SERIAL_FLUSHTX();
       };
 
       uint32_t s, e;
 
-      SERIAL_ECHOLNPAIR("Computed delay calibration value: ", ASM_CYCLES_PER_ITERATION);
+      SERIAL_ECHOLNPGM("Computed delay calibration value: ", ASM_CYCLES_PER_ITERATION);
       SERIAL_FLUSH();
       // Display the results of the calibration above
       constexpr uint32_t testValues[] = { 1, 5, 10, 20, 50, 100, 150, 200, 350, 500, 750, 1000 };

Marlin/src/MarlinCore.cpp

 void idle(bool no_stepper_sleep/*=false*/) {
   #if ENABLED(MARLIN_DEV_MODE)
     static uint16_t idle_depth = 0;
-    if (++idle_depth > 5) SERIAL_ECHOLNPAIR("idle() call depth: ", idle_depth);
+    if (++idle_depth > 5) SERIAL_ECHOLNPGM("idle() call depth: ", idle_depth);
   #endif
 
   // Core Marlin activities
   #if BOTH(HAS_WIRED_LCD, SHOW_BOOTSCREEN)
     const millis_t elapsed = millis() - bootscreen_ms;
     #if ENABLED(MARLIN_DEV_MODE)
-      SERIAL_ECHOLNPAIR("elapsed=", elapsed);
+      SERIAL_ECHOLNPGM("elapsed=", elapsed);
     #endif
     SETUP_RUN(ui.bootscreen_completion(elapsed));
   #endif

Marlin/src/core/bug_on.h

  */
 #pragma once
 
-// We need SERIAL_ECHOPAIR and macros.h
+// We need SERIAL_ECHOPGM and macros.h
 #include "serial.h"
 
 #if ENABLED(POSTMORTEM_DEBUGGING)
   // Useful macro for stopping the CPU on an unexpected condition
-  // This is used like SERIAL_ECHOPAIR, that is: a key-value call of the local variables you want
+  // This is used like SERIAL_ECHOPGM, that is: a key-value call of the local variables you want
   // to dump to the serial port before stopping the CPU.
-                          // \/ Don't replace by SERIAL_ECHOPAIR since ONLY_FILENAME cannot be transformed to a PGM string on Arduino and it breaks building
-  #define BUG_ON(V...) do { SERIAL_ECHO(ONLY_FILENAME); SERIAL_ECHO(__LINE__); SERIAL_ECHOLNPGM(": "); SERIAL_ECHOLNPAIR(V); SERIAL_FLUSHTX(); *(char*)0 = 42; } while(0)
+                          // \/ Don't replace by SERIAL_ECHOPGM since ONLY_FILENAME cannot be transformed to a PGM string on Arduino and it breaks building
+  #define BUG_ON(V...) do { SERIAL_ECHO(ONLY_FILENAME); SERIAL_ECHO(__LINE__); SERIAL_ECHOLNPGM(": "); SERIAL_ECHOLNPGM(V); SERIAL_FLUSHTX(); *(char*)0 = 42; } while(0)
 #elif ENABLED(MARLIN_DEV_MODE)
   // Don't stop the CPU here, but at least dump the bug on the serial port
-                          // \/ Don't replace by SERIAL_ECHOPAIR since ONLY_FILENAME cannot be transformed to a PGM string on Arduino and it breaks building
-  #define BUG_ON(V...) do { SERIAL_ECHO(ONLY_FILENAME); SERIAL_ECHO(__LINE__); SERIAL_ECHOLNPGM(": BUG!"); SERIAL_ECHOLNPAIR(V); SERIAL_FLUSHTX(); } while(0)
+                          // \/ Don't replace by SERIAL_ECHOPGM since ONLY_FILENAME cannot be transformed to a PGM string on Arduino and it breaks building
+  #define BUG_ON(V...) do { SERIAL_ECHO(ONLY_FILENAME); SERIAL_ECHO(__LINE__); SERIAL_ECHOLNPGM(": BUG!"); SERIAL_ECHOLNPGM(V); SERIAL_FLUSHTX(); } while(0)
 #else
   // Release mode, let's ignore the bug
   #define BUG_ON(V...) NOOP

Marlin/src/core/debug_out.h

 //
 
 #undef DEBUG_SECTION
-#undef DEBUG_ECHOPGM_P
 #undef DEBUG_ECHO_START
 #undef DEBUG_ERROR_START
 #undef DEBUG_CHAR
 #undef DEBUG_ECHOLN
 #undef DEBUG_ECHOPGM
 #undef DEBUG_ECHOLNPGM
-#undef DEBUG_ECHOPAIR
-#undef DEBUG_ECHOPAIR_P
+#undef DEBUG_ECHOPGM_P
+#undef DEBUG_ECHOLNPGM_P
 #undef DEBUG_ECHOPAIR_F
 #undef DEBUG_ECHOPAIR_F_P
-#undef DEBUG_ECHOLNPAIR
-#undef DEBUG_ECHOLNPAIR_P
 #undef DEBUG_ECHOLNPAIR_F
 #undef DEBUG_ECHOLNPAIR_F_P
 #undef DEBUG_ECHO_MSG
   #define DEBUG_ECHOLN            SERIAL_ECHOLN
   #define DEBUG_ECHOPGM           SERIAL_ECHOPGM
   #define DEBUG_ECHOLNPGM         SERIAL_ECHOLNPGM
-  #define DEBUG_ECHOPAIR          SERIAL_ECHOPAIR
-  #define DEBUG_ECHOPAIR_P        SERIAL_ECHOPAIR_P
+  #define DEBUG_ECHOPGM           SERIAL_ECHOPGM
+  #define DEBUG_ECHOPGM_P         SERIAL_ECHOPGM_P
   #define DEBUG_ECHOPAIR_F        SERIAL_ECHOPAIR_F
   #define DEBUG_ECHOPAIR_F_P      SERIAL_ECHOPAIR_F_P
-  #define DEBUG_ECHOLNPAIR        SERIAL_ECHOLNPAIR
-  #define DEBUG_ECHOLNPAIR_P      SERIAL_ECHOLNPAIR_P
+  #define DEBUG_ECHOLNPGM         SERIAL_ECHOLNPGM
+  #define DEBUG_ECHOLNPGM_P       SERIAL_ECHOLNPGM_P
   #define DEBUG_ECHOLNPAIR_F      SERIAL_ECHOLNPAIR_F
   #define DEBUG_ECHOLNPAIR_F_P    SERIAL_ECHOLNPAIR_F_P
   #define DEBUG_ECHO_MSG          SERIAL_ECHO_MSG
 #else
 
   #define DEBUG_SECTION(...)        NOOP
-  #define DEBUG_ECHOPGM_P(P)          NOOP
   #define DEBUG_ECHO_START()        NOOP
   #define DEBUG_ERROR_START()       NOOP
   #define DEBUG_CHAR(...)           NOOP
   #define DEBUG_ECHOLN(...)         NOOP
   #define DEBUG_ECHOPGM(...)        NOOP
   #define DEBUG_ECHOLNPGM(...)      NOOP
-  #define DEBUG_ECHOPAIR(...)       NOOP
-  #define DEBUG_ECHOPAIR_P(...)     NOOP
+  #define DEBUG_ECHOPGM_P(...)      NOOP
+  #define DEBUG_ECHOLNPGM_P(...)    NOOP
   #define DEBUG_ECHOPAIR_F(...)     NOOP
   #define DEBUG_ECHOPAIR_F_P(...)   NOOP
-  #define DEBUG_ECHOLNPAIR(...)     NOOP
-  #define DEBUG_ECHOLNPAIR_P(...)   NOOP
   #define DEBUG_ECHOLNPAIR_F(...)   NOOP
   #define DEBUG_ECHOLNPAIR_F_P(...) NOOP
   #define DEBUG_ECHO_MSG(...)       NOOP

Marlin/src/core/serial.cpp

 
 void print_pos(LINEAR_AXIS_ARGS(const_float_t), PGM_P const prefix/*=nullptr*/, PGM_P const suffix/*=nullptr*/) {
   if (prefix) serialprintPGM(prefix);
-  SERIAL_ECHOPAIR_P(
+  SERIAL_ECHOPGM_P(
     LIST_N(DOUBLE(LINEAR_AXES), SP_X_STR, x, SP_Y_STR, y, SP_Z_STR, z, SP_I_STR, i, SP_J_STR, j, SP_K_STR, k)
   );
   if (suffix) serialprintPGM(suffix); else SERIAL_EOL();

Marlin/src/core/serial.h

 void serialprintPGM(PGM_P str);
 
 //
-// SERIAL_ECHOPAIR... macros are used to output string-value pairs.
+// SERIAL_ECHOPGM... macros are used to output string-value pairs.
 //
 
 // Print up to 20 pairs of values. Odd elements must be literal strings.
 #define __SEP_N(N,V...)           _SEP_##N(V)
 #define _SEP_N(N,V...)            __SEP_N(N,V)
 #define _SEP_N_REF()              _SEP_N
-#define _SEP_1(s)                 SERIAL_ECHOPGM(s);
+#define _SEP_1(s)                 serialprintPGM(PSTR(s));
 #define _SEP_2(s,v)               serial_echopair_PGM(PSTR(s),v);
 #define _SEP_3(s,v,V...)          _SEP_2(s,v); DEFER2(_SEP_N_REF)()(TWO_ARGS(V),V);
-#define SERIAL_ECHOPAIR(V...)     do{ EVAL(_SEP_N(TWO_ARGS(V),V)); }while(0)
+#define SERIAL_ECHOPGM(V...)      do{ EVAL(_SEP_N(TWO_ARGS(V),V)); }while(0)
 
 // Print up to 20 pairs of values followed by newline. Odd elements must be literal strings.
 #define __SELP_N(N,V...)          _SELP_##N(V)
 #define _SELP_N(N,V...)           __SELP_N(N,V)
 #define _SELP_N_REF()             _SELP_N
-#define _SELP_1(s)                SERIAL_ECHOLNPGM(s);
+#define _SELP_1(s)                serialprintPGM(PSTR(s "\n"));
 #define _SELP_2(s,v)              serial_echopair_PGM(PSTR(s),v); SERIAL_EOL();
 #define _SELP_3(s,v,V...)         _SEP_2(s,v); DEFER2(_SELP_N_REF)()(TWO_ARGS(V),V);
-#define SERIAL_ECHOLNPAIR(V...)   do{ EVAL(_SELP_N(TWO_ARGS(V),V)); }while(0)
+#define SERIAL_ECHOLNPGM(V...)    do{ EVAL(_SELP_N(TWO_ARGS(V),V)); }while(0)
 
 // Print up to 20 pairs of values. Odd elements must be PSTR pointers.
 #define __SEP_N_P(N,V...)         _SEP_##N##_P(V)
 #define _SEP_N_P(N,V...)          __SEP_N_P(N,V)
 #define _SEP_N_P_REF()            _SEP_N_P
-#define _SEP_1_P(s)               serialprintPGM(s);
-#define _SEP_2_P(s,v)             serial_echopair_PGM(s,v);
-#define _SEP_3_P(s,v,V...)        _SEP_2_P(s,v); DEFER2(_SEP_N_P_REF)()(TWO_ARGS(V),V);
-#define SERIAL_ECHOPAIR_P(V...)   do{ EVAL(_SEP_N_P(TWO_ARGS(V),V)); }while(0)
+#define _SEP_1_P(p)               serialprintPGM(p);
+#define _SEP_2_P(p,v)             serial_echopair_PGM(p,v);
+#define _SEP_3_P(p,v,V...)        _SEP_2_P(p,v); DEFER2(_SEP_N_P_REF)()(TWO_ARGS(V),V);
+#define SERIAL_ECHOPGM_P(V...)    do{ EVAL(_SEP_N_P(TWO_ARGS(V),V)); }while(0)
 
 // Print up to 20 pairs of values followed by newline. Odd elements must be PSTR pointers.
 #define __SELP_N_P(N,V...)        _SELP_##N##_P(V)
 #define _SELP_N_P(N,V...)         __SELP_N_P(N,V)
 #define _SELP_N_P_REF()           _SELP_N_P
-#define _SELP_1_P(s)              { serialprintPGM(s); SERIAL_EOL(); }
-#define _SELP_2_P(s,v)            { serial_echopair_PGM(s,v); SERIAL_EOL(); }
-#define _SELP_3_P(s,v,V...)       { _SEP_2_P(s,v); DEFER2(_SELP_N_P_REF)()(TWO_ARGS(V),V); }
-#define SERIAL_ECHOLNPAIR_P(V...) do{ EVAL(_SELP_N_P(TWO_ARGS(V),V)); }while(0)
+#define _SELP_1_P(p)              { serialprintPGM(p); SERIAL_EOL(); }
+#define _SELP_2_P(p,v)            { serial_echopair_PGM(p,v); SERIAL_EOL(); }
+#define _SELP_3_P(p,v,V...)       { _SEP_2_P(p,v); DEFER2(_SELP_N_P_REF)()(TWO_ARGS(V),V); }
+#define SERIAL_ECHOLNPGM_P(V...)  do{ EVAL(_SELP_N_P(TWO_ARGS(V),V)); }while(0)
 
 #ifdef AllowDifferentTypeInList
 
 
 #endif
 
-#define SERIAL_ECHOPGM_P(P)         (serialprintPGM(P))
-#define SERIAL_ECHOLNPGM_P(P)       do{ serialprintPGM(P); SERIAL_EOL(); }while(0)
-
-#define SERIAL_ECHOPGM(S)           (serialprintPGM(PSTR(S)))
-#define SERIAL_ECHOLNPGM(S)         (serialprintPGM(PSTR(S "\n")))
-
 #define SERIAL_ECHOPAIR_F_P(P,V...) do{ serialprintPGM(P); SERIAL_ECHO_F(V); }while(0)
 #define SERIAL_ECHOLNPAIR_F_P(V...) do{ SERIAL_ECHOPAIR_F_P(V); SERIAL_EOL(); }while(0)
 
 #define SERIAL_ERROR_START()        serial_error_start()
 #define SERIAL_EOL()                SERIAL_CHAR('\n')
 
-#define SERIAL_ECHO_MSG(V...)       do{ SERIAL_ECHO_START(); SERIAL_ECHOLNPAIR(V); }while(0)
-#define SERIAL_ERROR_MSG(V...)      do{ SERIAL_ERROR_START(); SERIAL_ECHOLNPAIR(V); }while(0)
+#define SERIAL_ECHO_MSG(V...)       do{ SERIAL_ECHO_START();  SERIAL_ECHOLNPGM(V); }while(0)
+#define SERIAL_ERROR_MSG(V...)      do{ SERIAL_ERROR_START(); SERIAL_ECHOLNPGM(V); }while(0)
 
 #define SERIAL_ECHO_SP(C)           serial_spaces(C)
 

Marlin/src/core/utility.cpp

     #if HAS_BED_PROBE
 
       #if !HAS_PROBE_XY_OFFSET
-        SERIAL_ECHOPAIR("Probe Offset X0 Y0 Z", probe.offset.z, " (");
+        SERIAL_ECHOPGM("Probe Offset X0 Y0 Z", probe.offset.z, " (");
       #else
-        SERIAL_ECHOPAIR_P(PSTR("Probe Offset X"), probe.offset_xy.x, SP_Y_STR, probe.offset_xy.y, SP_Z_STR, probe.offset.z);
+        SERIAL_ECHOPGM_P(PSTR("Probe Offset X"), probe.offset_xy.x, SP_Y_STR, probe.offset_xy.y, SP_Z_STR, probe.offset.z);
         if (probe.offset_xy.x > 0)
           SERIAL_ECHOPGM(" (Right");
         else if (probe.offset_xy.x < 0)
         SERIAL_ECHOLNPGM(" (enabled)");
         #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
           if (planner.z_fade_height)
-            SERIAL_ECHOLNPAIR("Z Fade: ", planner.z_fade_height);
+            SERIAL_ECHOLNPGM("Z Fade: ", planner.z_fade_height);
         #endif
         #if ABL_PLANAR
           SERIAL_ECHOPGM("ABL Adjustment");
           SERIAL_ECHO(ftostr43sign(rz, '+'));
           #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
             if (planner.z_fade_height) {
-              SERIAL_ECHOPAIR(" (", ftostr43sign(rz * planner.fade_scaling_factor_for_z(current_position.z), '+'));
+              SERIAL_ECHOPGM(" (", ftostr43sign(rz * planner.fade_scaling_factor_for_z(current_position.z), '+'));
               SERIAL_CHAR(')');
             }
           #endif
       SERIAL_ECHOPGM("Mesh Bed Leveling");
       if (planner.leveling_active) {
         SERIAL_ECHOLNPGM(" (enabled)");
-        SERIAL_ECHOPAIR("MBL Adjustment Z", ftostr43sign(mbl.get_z(current_position), '+'));
+        SERIAL_ECHOPGM("MBL Adjustment Z", ftostr43sign(mbl.get_z(current_position), '+'));
         #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
           if (planner.z_fade_height) {
-            SERIAL_ECHOPAIR(" (", ftostr43sign(
+            SERIAL_ECHOPGM(" (", ftostr43sign(
               mbl.get_z(current_position, planner.fade_scaling_factor_for_z(current_position.z)), '+'
             ));
             SERIAL_CHAR(')');

Marlin/src/feature/backlash.cpp

           switch (axis) {
             case CORE_AXIS_1:
               //block->steps[CORE_AXIS_2] += influence_distance_mm[axis] * planner.settings.axis_steps_per_mm[CORE_AXIS_2];
-              //SERIAL_ECHOLNPAIR("CORE_AXIS_1 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
+              //SERIAL_ECHOLNPGM("CORE_AXIS_1 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
               //  " da=", da, " db=", db, " block->steps[axis]=", block->steps[axis], " err_corr=", error_correction);
               break;
             case CORE_AXIS_2:
               //block->steps[CORE_AXIS_1] += influence_distance_mm[axis] * planner.settings.axis_steps_per_mm[CORE_AXIS_1];;
-              //SERIAL_ECHOLNPAIR("CORE_AXIS_2 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
+              //SERIAL_ECHOLNPGM("CORE_AXIS_2 dir change. distance=", distance_mm[axis], " r.err=", residual_error[axis],
               //  " da=", da, " db=", db, " block->steps[axis]=", block->steps[axis], " err_corr=", error_correction);
               break;
             case NORMAL_AXIS: break;

Marlin/src/feature/bedlevel/abl/abl.cpp

   /*
   static float last_offset = 0;
   if (ABS(last_offset - offset) > 0.2) {
-    SERIAL_ECHOLNPAIR("Sudden Shift at x=", rel.x, " / ", bilinear_grid_spacing.x, " -> thisg.x=", thisg.x);
-    SERIAL_ECHOLNPAIR(" y=", rel.y, " / ", bilinear_grid_spacing.y, " -> thisg.y=", thisg.y);
-    SERIAL_ECHOLNPAIR(" ratio.x=", ratio.x, " ratio.y=", ratio.y);
-    SERIAL_ECHOLNPAIR(" z1=", z1, " z2=", z2, " z3=", z3, " z4=", z4);
-    SERIAL_ECHOLNPAIR(" L=", L, " R=", R, " offset=", offset);
+    SERIAL_ECHOLNPGM("Sudden Shift at x=", rel.x, " / ", bilinear_grid_spacing.x, " -> thisg.x=", thisg.x);
+    SERIAL_ECHOLNPGM(" y=", rel.y, " / ", bilinear_grid_spacing.y, " -> thisg.y=", thisg.y);
+    SERIAL_ECHOLNPGM(" ratio.x=", ratio.x, " ratio.y=", ratio.y);
+    SERIAL_ECHOLNPGM(" z1=", z1, " z2=", z2, " z3=", z3, " z4=", z4);
+    SERIAL_ECHOLNPGM(" L=", L, " R=", R, " offset=", offset);
   }
   last_offset = offset;
   //*/

Marlin/src/feature/bedlevel/ubl/ubl.cpp

   GRID_LOOP(x, y)
     if (!isnan(z_values[x][y])) {
       SERIAL_ECHO_START();
-      SERIAL_ECHOPAIR("  M421 I", x, " J", y);
+      SERIAL_ECHOPGM("  M421 I", x, " J", y);
       SERIAL_ECHOLNPAIR_F_P(SP_Z_STR, z_values[x][y], 4);
       serial_delay(75); // Prevent Printrun from exploding
     }

Marlin/src/feature/bedlevel/ubl/ubl.h

 
       if (DEBUGGING(LEVELING)) {
         if (WITHIN(x1_i, 0, (GRID_MAX_POINTS_X) - 1)) DEBUG_ECHOPGM("yi"); else DEBUG_ECHOPGM("x1_i");
-        DEBUG_ECHOLNPAIR(" out of bounds in z_correction_for_x_on_horizontal_mesh_line(rx0=", rx0, ",x1_i=", x1_i, ",yi=", yi, ")");
+        DEBUG_ECHOLNPGM(" out of bounds in z_correction_for_x_on_horizontal_mesh_line(rx0=", rx0, ",x1_i=", x1_i, ",yi=", yi, ")");
       }
 
       // The requested location is off the mesh. Return UBL_Z_RAISE_WHEN_OFF_MESH or NAN.
 
       if (DEBUGGING(LEVELING)) {
         if (WITHIN(xi, 0, (GRID_MAX_POINTS_X) - 1)) DEBUG_ECHOPGM("y1_i"); else DEBUG_ECHOPGM("xi");
-        DEBUG_ECHOLNPAIR(" out of bounds in z_correction_for_y_on_vertical_mesh_line(ry0=", ry0, ", xi=", xi, ", y1_i=", y1_i, ")");
+        DEBUG_ECHOLNPGM(" out of bounds in z_correction_for_y_on_vertical_mesh_line(ry0=", ry0, ", xi=", xi, ", y1_i=", y1_i, ")");
       }
 
       // The requested location is off the mesh. Return UBL_Z_RAISE_WHEN_OFF_MESH or NAN.
                      // because part of the Mesh is undefined and we don't have the
                      // information we need to complete the height correction.
 
-      if (DEBUGGING(MESH_ADJUST)) DEBUG_ECHOLNPAIR("??? Yikes! NAN in ");
+      if (DEBUGGING(MESH_ADJUST)) DEBUG_ECHOLNPGM("??? Yikes! NAN in ");
     }
 
     if (DEBUGGING(MESH_ADJUST)) {
-      DEBUG_ECHOPAIR("get_z_correction(", rx0, ", ", ry0);
+      DEBUG_ECHOPGM("get_z_correction(", rx0, ", ", ry0);
       DEBUG_ECHOLNPAIR_F(") => ", z0, 6);
     }
 

Marlin/src/feature/bedlevel/ubl/ubl_G29.cpp

             SERIAL_ECHOLNPGM("Mesh invalidated. Probing mesh.");
           }
           if (param.V_verbosity > 1) {
-            SERIAL_ECHOPAIR("Probing around (", param.XY_pos.x);
+            SERIAL_ECHOPGM("Probing around (", param.XY_pos.x);
             SERIAL_CHAR(',');
             SERIAL_DECIMAL(param.XY_pos.y);
             SERIAL_ECHOLNPGM(").\n");
     }
 
     if (!WITHIN(param.KLS_storage_slot, 0, a - 1)) {
-      SERIAL_ECHOLNPAIR("?Invalid storage slot.\n?Use 0 to ", a - 1);
+      SERIAL_ECHOLNPGM("?Invalid storage slot.\n?Use 0 to ", a - 1);
       return;
     }
 
     }
 
     if (!WITHIN(param.KLS_storage_slot, 0, a - 1)) {
-      SERIAL_ECHOLNPAIR("?Invalid storage slot.\n?Use 0 to ", a - 1);
+      SERIAL_ECHOLNPGM("?Invalid storage slot.\n?Use 0 to ", a - 1);
       goto LEAVE;
     }
 
   #endif
 
   #ifdef Z_PROBE_END_SCRIPT
-    if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("Z Probe End Script: ", Z_PROBE_END_SCRIPT);
+    if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("Z Probe End Script: ", Z_PROBE_END_SCRIPT);
     if (probe_deployed) {
       planner.synchronize();
       gcode.process_subcommands_now_P(PSTR(Z_PROBE_END_SCRIPT));
     if (!isnan(z_values[x][y]))
       sum_of_diff_squared += sq(z_values[x][y] - mean);
 
-  SERIAL_ECHOLNPAIR("# of samples: ", n);
+  SERIAL_ECHOLNPGM("# of samples: ", n);
   SERIAL_ECHOLNPAIR_F("Mean Mesh Height: ", mean, 6);
 
   const float sigma = SQRT(sum_of_diff_squared / (n + 1));
       if (do_ubl_mesh_map) display_map(param.T_map_type);
 
       const uint8_t point_num = (GRID_MAX_POINTS - count) + 1;
-      SERIAL_ECHOLNPAIR("Probing mesh point ", point_num, "/", GRID_MAX_POINTS, ".");
+      SERIAL_ECHOLNPGM("Probing mesh point ", point_num, "/", GRID_MAX_POINTS, ".");
       TERN_(HAS_STATUS_MESSAGE, ui.status_printf_P(0, PSTR(S_FMT " %i/%i"), GET_TEXT(MSG_PROBING_POINT), point_num, int(GRID_MAX_POINTS)));
 
       #if HAS_LCD_MENU
         #endif
         if (param.V_verbosity > 3) {
           serial_spaces(16);
-          SERIAL_ECHOLNPAIR("Corrected_Z=", measured_z);
+          SERIAL_ECHOLNPGM("Corrected_Z=", measured_z);
         }
         incremental_LSF(&lsf_results, points[0], measured_z);
       }
           measured_z -= get_z_correction(points[1]);
           if (param.V_verbosity > 3) {
             serial_spaces(16);
-            SERIAL_ECHOLNPAIR("Corrected_Z=", measured_z);
+            SERIAL_ECHOLNPGM("Corrected_Z=", measured_z);
           }
           incremental_LSF(&lsf_results, points[1], measured_z);
         }
           measured_z -= get_z_correction(points[2]);
           if (param.V_verbosity > 3) {
             serial_spaces(16);
-            SERIAL_ECHOLNPAIR("Corrected_Z=", measured_z);
+            SERIAL_ECHOLNPGM("Corrected_Z=", measured_z);
           }
           incremental_LSF(&lsf_results, points[2], measured_z);
         }
           rpos.y = y_min + dy * (zig_zag ? param.J_grid_size - 1 - iy : iy);
 
           if (!abort_flag) {
-            SERIAL_ECHOLNPAIR("Tilting mesh point ", point_num, "/", total_points, "\n");
+            SERIAL_ECHOLNPGM("Tilting mesh point ", point_num, "/", total_points, "\n");
             TERN_(HAS_STATUS_MESSAGE, ui.status_printf_P(0, PSTR(S_FMT " %i/%i"), GET_TEXT(MSG_LCD_TILTING_MESH), point_num, total_points));
 
             measured_z = probe.probe_at_point(rpos, parser.seen_test('E') ? PROBE_PT_STOW : PROBE_PT_RAISE, param.V_verbosity); // TODO: Needs error handling
 
             if (param.V_verbosity > 3) {
               serial_spaces(16);
-              SERIAL_ECHOLNPAIR("Corrected_Z=", measured_z);
+              SERIAL_ECHOLNPGM("Corrected_Z=", measured_z);
             }
             incremental_LSF(&lsf_results, rpos, measured_z);
           }
         DEBUG_ECHOLNPAIR_F("0 : ", normed(safe_homing_xy, 0), 6);
         d_from(); DEBUG_ECHOPGM("safe home with Z=");
         DEBUG_ECHOLNPAIR_F("mesh value ", normed(safe_homing_xy, get_z_correction(safe_homing_xy)), 6);
-        DEBUG_ECHOPAIR("   Z error = (", Z_SAFE_HOMING_X_POINT, ",", Z_SAFE_HOMING_Y_POINT);
+        DEBUG_ECHOPGM("   Z error = (", Z_SAFE_HOMING_X_POINT, ",", Z_SAFE_HOMING_Y_POINT);
         DEBUG_ECHOLNPAIR_F(") = ", get_z_correction(safe_homing_xy), 6);
       #endif
     } // DEBUGGING(LEVELING)
     if (storage_slot == -1)
       SERIAL_ECHOPGM("No Mesh Loaded.");
     else
-      SERIAL_ECHOPAIR("Mesh ", storage_slot, " Loaded.");
+      SERIAL_ECHOPGM("Mesh ", storage_slot, " Loaded.");
     SERIAL_EOL();
     serial_delay(50);
 
       SERIAL_ECHOLNPAIR_F("Probe Offset M851 Z", probe.offset.z, 7);
     #endif
 
-    SERIAL_ECHOLNPAIR("MESH_MIN_X  " STRINGIFY(MESH_MIN_X) "=", MESH_MIN_X); serial_delay(50);
-    SERIAL_ECHOLNPAIR("MESH_MIN_Y  " STRINGIFY(MESH_MIN_Y) "=", MESH_MIN_Y); serial_delay(50);
-    SERIAL_ECHOLNPAIR("MESH_MAX_X  " STRINGIFY(MESH_MAX_X) "=", MESH_MAX_X); serial_delay(50);
-    SERIAL_ECHOLNPAIR("MESH_MAX_Y  " STRINGIFY(MESH_MAX_Y) "=", MESH_MAX_Y); serial_delay(50);
-    SERIAL_ECHOLNPAIR("GRID_MAX_POINTS_X  ", GRID_MAX_POINTS_X);             serial_delay(50);
-    SERIAL_ECHOLNPAIR("GRID_MAX_POINTS_Y  ", GRID_MAX_POINTS_Y);             serial_delay(50);
-    SERIAL_ECHOLNPAIR("MESH_X_DIST  ", MESH_X_DIST);
-    SERIAL_ECHOLNPAIR("MESH_Y_DIST  ", MESH_Y_DIST);                         serial_delay(50);
+    SERIAL_ECHOLNPGM("MESH_MIN_X  " STRINGIFY(MESH_MIN_X) "=", MESH_MIN_X); serial_delay(50);
+    SERIAL_ECHOLNPGM("MESH_MIN_Y  " STRINGIFY(MESH_MIN_Y) "=", MESH_MIN_Y); serial_delay(50);
+    SERIAL_ECHOLNPGM("MESH_MAX_X  " STRINGIFY(MESH_MAX_X) "=", MESH_MAX_X); serial_delay(50);
+    SERIAL_ECHOLNPGM("MESH_MAX_Y  " STRINGIFY(MESH_MAX_Y) "=", MESH_MAX_Y); serial_delay(50);
+    SERIAL_ECHOLNPGM("GRID_MAX_POINTS_X  ", GRID_MAX_POINTS_X);             serial_delay(50);
+    SERIAL_ECHOLNPGM("GRID_MAX_POINTS_Y  ", GRID_MAX_POINTS_Y);             serial_delay(50);
+    SERIAL_ECHOLNPGM("MESH_X_DIST  ", MESH_X_DIST);
+    SERIAL_ECHOLNPGM("MESH_Y_DIST  ", MESH_Y_DIST);                         serial_delay(50);
 
     SERIAL_ECHOPGM("X-Axis Mesh Points at: ");
     LOOP_L_N(i, GRID_MAX_POINTS_X) {
     SERIAL_EOL();
 
     #if HAS_KILL
-      SERIAL_ECHOLNPAIR("Kill pin on :", KILL_PIN, "  state:", kill_state());
+      SERIAL_ECHOLNPGM("Kill pin on :", KILL_PIN, "  state:", kill_state());
     #endif
 
     SERIAL_EOL();
     serial_delay(50);
 
     #if ENABLED(UBL_DEVEL_DEBUGGING)
-      SERIAL_ECHOLNPAIR("ubl_state_at_invocation :", ubl_state_at_invocation, "\nubl_state_recursion_chk :", ubl_state_recursion_chk);
+      SERIAL_ECHOLNPGM("ubl_state_at_invocation :", ubl_state_at_invocation, "\nubl_state_recursion_chk :", ubl_state_recursion_chk);
       serial_delay(50);
 
-      SERIAL_ECHOLNPAIR("Meshes go from ", hex_address((void*)settings.meshes_start_index()), " to ", hex_address((void*)settings.meshes_end_index()));
+      SERIAL_ECHOLNPGM("Meshes go from ", hex_address((void*)settings.meshes_start_index()), " to ", hex_address((void*)settings.meshes_end_index()));
       serial_delay(50);
 
-      SERIAL_ECHOLNPAIR("sizeof(ubl) :  ", sizeof(ubl));         SERIAL_EOL();
-      SERIAL_ECHOLNPAIR("z_value[][] size: ", sizeof(z_values)); SERIAL_EOL();
+      SERIAL_ECHOLNPGM("sizeof(ubl) :  ", sizeof(ubl));         SERIAL_EOL();
+      SERIAL_ECHOLNPGM("z_value[][] size: ", sizeof(z_values)); SERIAL_EOL();
       serial_delay(25);
 
-      SERIAL_ECHOLNPAIR("EEPROM free for UBL: ", hex_address((void*)(settings.meshes_end_index() - settings.meshes_start_index())));
+      SERIAL_ECHOLNPGM("EEPROM free for UBL: ", hex_address((void*)(settings.meshes_end_index() - settings.meshes_start_index())));
       serial_delay(50);
 
-      SERIAL_ECHOLNPAIR("EEPROM can hold ", settings.calc_num_meshes(), " meshes.\n");
+      SERIAL_ECHOLNPGM("EEPROM can hold ", settings.calc_num_meshes(), " meshes.\n");
       serial_delay(25);
     #endif // UBL_DEVEL_DEBUGGING
 
     }
 
     if (!parser.has_value() || !WITHIN(parser.value_int(), 0, a - 1)) {
-      SERIAL_ECHOLNPAIR("?Invalid storage slot.\n?Use 0 to ", a - 1);
+      SERIAL_ECHOLNPGM("?Invalid storage slot.\n?Use 0 to ", a - 1);
       return;
     }
 
     float tmp_z_values[GRID_MAX_POINTS_X][GRID_MAX_POINTS_Y];
     settings.load_mesh(param.KLS_storage_slot, &tmp_z_values);
 
-    SERIAL_ECHOLNPAIR("Subtracting mesh in slot ", param.KLS_storage_slot, " from current mesh.");
+    SERIAL_ECHOLNPGM("Subtracting mesh in slot ", param.KLS_storage_slot, " from current mesh.");
 
     GRID_LOOP(x, y) {
       z_values[x][y] -= tmp_z_values[x][y];

Marlin/src/feature/binary_stream.h

     transfer_timeout = millis() + TIMEOUT;
     switch (static_cast<FileTransfer>(packet_type)) {
       case FileTransfer::QUERY:
-        SERIAL_ECHOPAIR("PFT:version:", VERSION_MAJOR, ".", VERSION_MINOR, ".", VERSION_PATCH);
+        SERIAL_ECHOPGM("PFT:version:", VERSION_MAJOR, ".", VERSION_MINOR, ".", VERSION_PATCH);
         #if ENABLED(BINARY_STREAM_COMPRESSION)
-          SERIAL_ECHOLNPAIR(":compression:heatshrink,", HEATSHRINK_STATIC_WINDOW_BITS, ",", HEATSHRINK_STATIC_LOOKAHEAD_BITS);
+          SERIAL_ECHOLNPGM(":compression:heatshrink,", HEATSHRINK_STATIC_WINDOW_BITS, ",", HEATSHRINK_STATIC_LOOKAHEAD_BITS);
         #else
           SERIAL_ECHOLNPGM(":compression:none");
         #endif
             if (packet.header.checksum == packet.header_checksum) {
               // The SYNC control packet is a special case in that it doesn't require the stream sync to be correct
               if (static_cast<Protocol>(packet.header.protocol()) == Protocol::CONTROL && static_cast<ProtocolControl>(packet.header.type()) == ProtocolControl::SYNC) {
-                  SERIAL_ECHOLNPAIR("ss", sync, ",", buffer_size, ",", VERSION_MAJOR, ".", VERSION_MINOR, ".", VERSION_PATCH);
+                  SERIAL_ECHOLNPGM("ss", sync, ",", buffer_size, ",", VERSION_MAJOR, ".", VERSION_MINOR, ".", VERSION_PATCH);
                   stream_state = StreamState::PACKET_RESET;
                   break;
               }
                   stream_state = StreamState::PACKET_PROCESS;
               }
               else if (packet.header.sync == sync - 1) {           // ok response must have been lost
-                SERIAL_ECHOLNPAIR("ok", packet.header.sync);  // transmit valid packet received and drop the payload
+                SERIAL_ECHOLNPGM("ok", packet.header.sync);  // transmit valid packet received and drop the payload
                 stream_state = StreamState::PACKET_RESET;
               }
               else if (packet_retries) {
           packet_retries = 0;
           bytes_received += packet.header.size;
 
-          SERIAL_ECHOLNPAIR("ok", packet.header.sync); // transmit valid packet received
+          SERIAL_ECHOLNPGM("ok", packet.header.sync); // transmit valid packet received
           dispatch();
           stream_state = StreamState::PACKET_RESET;
           break;
             packet_retries++;
             stream_state = StreamState::PACKET_RESET;
             SERIAL_ECHO_MSG("Resend request ", packet_retries);
-            SERIAL_ECHOLNPAIR("rs", sync);
+            SERIAL_ECHOLNPGM("rs", sync);
           }
           else
             stream_state = StreamState::PACKET_ERROR;
           stream_state = StreamState::PACKET_RESEND;
           break;
         case StreamState::PACKET_ERROR:
-          SERIAL_ECHOLNPAIR("fe", packet.header.sync);
+          SERIAL_ECHOLNPGM("fe", packet.header.sync);
           reset(); // reset everything, resync required
           stream_state = StreamState::PACKET_RESET;
           break;

Marlin/src/feature/bltouch.cpp

 #include "../core/debug_out.h"
 
 bool BLTouch::command(const BLTCommand cmd, const millis_t &ms) {
-  if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPAIR("BLTouch Command :", cmd);
+  if (DEBUGGING(LEVELING)) SERIAL_ECHOLNPGM("BLTouch Command :", cmd);
   MOVE_SERVO(Z_PROBE_SERVO_NR, cmd);
   safe_delay(_MAX(ms, (uint32_t)BLTOUCH_DELAY)); // BLTOUCH_DELAY is also the *minimum* delay
   return triggered();
   #else
 
     if (DEBUGGING(LEVELING)) {
-      DEBUG_ECHOLNPAIR("last_written_mode - ", last_written_mode);
+      DEBUG_ECHOLNPGM("last_written_mode - ", last_written_mode);
       DEBUG_ECHOLNPGM("config mode - "
         #if ENABLED(BLTOUCH_SET_5V_MODE)
           "BLTOUCH_SET_5V_MODE"
   _set_SW_mode();              // Incidentally, _set_SW_mode() will also RESET any active alarm
   const bool tr = triggered(); // If triggered in SW mode, the pin is up, it is STOWED
 
-  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("BLTouch is ", tr);
+  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("BLTouch is ", tr);
 
   if (tr) _stow(); else _deploy();  // Turn off SW mode, reset any trigger, honor pin state
   return !tr;
    * BLTOUCH V3.0: This will set the mode (twice) and sadly, a STOW is needed at the end, because of the deploy
    * BLTOUCH V3.1: This will set the mode and store it in the eeprom. The STOW is not needed but does not hurt
    */
-  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("BLTouch Set Mode - ", M5V);
+  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("BLTouch Set Mode - ", M5V);
   _deploy();
   if (M5V) _set_5V_mode(); else _set_OD_mode();
   _mode_store();

Marlin/src/feature/dac/stepper_dac.cpp

   if (!dac_present) return;
   SERIAL_ECHO_MSG("Stepper current values in % (Amps):");
   SERIAL_ECHO_START();
-  SERIAL_ECHOPAIR_P(SP_X_LBL, dac_perc(X_AXIS), PSTR(" ("), dac_amps(X_AXIS), PSTR(")"));
+  SERIAL_ECHOPGM_P(SP_X_LBL, dac_perc(X_AXIS), PSTR(" ("), dac_amps(X_AXIS), PSTR(")"));
   #if HAS_Y_AXIS
-    SERIAL_ECHOPAIR_P(SP_Y_LBL, dac_perc(Y_AXIS), PSTR(" ("), dac_amps(Y_AXIS), PSTR(")"));
+    SERIAL_ECHOPGM_P(SP_Y_LBL, dac_perc(Y_AXIS), PSTR(" ("), dac_amps(Y_AXIS), PSTR(")"));
   #endif
   #if HAS_Z_AXIS
-    SERIAL_ECHOPAIR_P(SP_Z_LBL, dac_perc(Z_AXIS), PSTR(" ("), dac_amps(Z_AXIS), PSTR(")"));
+    SERIAL_ECHOPGM_P(SP_Z_LBL, dac_perc(Z_AXIS), PSTR(" ("), dac_amps(Z_AXIS), PSTR(")"));
   #endif
   #if HAS_EXTRUDERS
-    SERIAL_ECHOLNPAIR_P(SP_E_LBL, dac_perc(E_AXIS), PSTR(" ("), dac_amps(E_AXIS), PSTR(")"));
+    SERIAL_ECHOLNPGM_P(SP_E_LBL, dac_perc(E_AXIS), PSTR(" ("), dac_amps(E_AXIS), PSTR(")"));
   #endif
 }
 

Marlin/src/feature/encoder_i2c.cpp

 
   initialized = true;
 
-  SERIAL_ECHOLNPAIR("Setting up encoder on ", AS_CHAR(axis_codes[encoderAxis]), " axis, addr = ", address);
+  SERIAL_ECHOLNPGM("Setting up encoder on ", AS_CHAR(axis_codes[encoderAxis]), " axis, addr = ", address);
 
   position = get_position();
 }
     /*
     if (trusted) { //commented out as part of the note below
       trusted = false;
-      SERIAL_ECHOLNPAIR("Fault detected on ", AS_CHAR(axis_codes[encoderAxis]), " axis encoder. Disengaging error correction until module is trusted again.");
+      SERIAL_ECHOLNPGM("Fault detected on ", AS_CHAR(axis_codes[encoderAxis]), " axis encoder. Disengaging error correction until module is trusted again.");
     }
     */
     return;
       if (millis() - lastErrorTime > I2CPE_TIME_TRUSTED) {
         trusted = true;
 
-        SERIAL_ECHOLNPAIR("Untrusted encoder module on ", AS_CHAR(axis_codes[encoderAxis]), " axis has been fault-free for set duration, reinstating error correction.");
+        SERIAL_ECHOLNPGM("Untrusted encoder module on ", AS_CHAR(axis_codes[encoderAxis]), " axis has been fault-free for set duration, reinstating error correction.");
 
         //the encoder likely lost its place when the error occurred, so we'll reset and use the printer's
         //idea of where it the axis is to re-initialize
         zeroOffset -= (positionInTicks - get_position());
 
         #ifdef I2CPE_DEBUG
-          SERIAL_ECHOLNPAIR("Current position is ", pos);
-          SERIAL_ECHOLNPAIR("Position in encoder ticks is ", positionInTicks);
-          SERIAL_ECHOLNPAIR("New zero-offset of ", zeroOffset);
-          SERIAL_ECHOPAIR("New position reads as ", get_position());
+          SERIAL_ECHOLNPGM("Current position is ", pos);
+          SERIAL_ECHOLNPGM("Position in encoder ticks is ", positionInTicks);
+          SERIAL_ECHOLNPGM("New zero-offset of ", zeroOffset);
+          SERIAL_ECHOPGM("New position reads as ", get_position());
           SERIAL_CHAR('(');
           SERIAL_DECIMAL(mm_from_count(get_position()));
           SERIAL_ECHOLNPGM(")");
       const int32_t error = get_axis_error_steps(false);
     #endif
 
-    //SERIAL_ECHOLNPAIR("Axis error steps: ", error);
+    //SERIAL_ECHOLNPGM("Axis error steps: ", error);
 
     #ifdef I2CPE_ERR_THRESH_ABORT
       if (ABS(error) > I2CPE_ERR_THRESH_ABORT * planner.settings.axis_steps_per_mm[encoderAxis]) {
         //kill(PSTR("Significant Error"));
-        SERIAL_ECHOLNPAIR("Axis error over threshold, aborting!", error);
+        SERIAL_ECHOLNPGM("Axis error over threshold, aborting!", error);
         safe_delay(5000);
       }
     #endif
             LOOP_L_N(i, I2CPE_ERR_PRST_ARRAY_SIZE) sumP += errPrst[i];
             const int32_t errorP = int32_t(sumP * RECIPROCAL(I2CPE_ERR_PRST_ARRAY_SIZE));
             SERIAL_CHAR(axis_codes[encoderAxis]);
-            SERIAL_ECHOLNPAIR(" : CORRECT ERR ", errorP * planner.steps_to_mm[encoderAxis], "mm");
+            SERIAL_ECHOLNPGM(" : CORRECT ERR ", errorP * planner.steps_to_mm[encoderAxis], "mm");
             babystep.add_steps(encoderAxis, -LROUND(errorP));
             errPrstIdx = 0;
           }
       const millis_t ms = millis();
       if (ELAPSED(ms, nextErrorCountTime)) {
         SERIAL_CHAR(axis_codes[encoderAxis]);
-        SERIAL_ECHOLNPAIR(" : LARGE ERR ", error, "; diffSum=", diffSum);
+        SERIAL_ECHOLNPGM(" : LARGE ERR ", error, "; diffSum=", diffSum);
         errorCount++;
         nextErrorCountTime = ms + I2CPE_ERR_CNT_DEBOUNCE_MS;
       }
 
     #ifdef I2CPE_DEBUG
       SERIAL_CHAR(axis_codes[encoderAxis]);
-      SERIAL_ECHOLNPAIR(" axis encoder homed, offset of ", zeroOffset, " ticks.");
+      SERIAL_ECHOLNPGM(" axis encoder homed, offset of ", zeroOffset, " ticks.");
     #endif
   }
 }
 
   if (report) {
     SERIAL_CHAR(axis_codes[encoderAxis]);
-    SERIAL_ECHOLNPAIR(" axis target=", target, "mm; actual=", actual, "mm; err=", error, "mm");
+    SERIAL_ECHOLNPGM(" axis target=", target, "mm; actual=", actual, "mm; err=", error, "mm");
   }
 
   return error;
 
   if (report) {
     SERIAL_CHAR(axis_codes[encoderAxis]);
-    SERIAL_ECHOLNPAIR(" axis target=", target, "; actual=", encoderCountInStepperTicksScaled, "; err=", error);
+    SERIAL_ECHOLNPGM(" axis target=", target, "; actual=", encoderCountInStepperTicksScaled, "; err=", error);
   }
 
   if (suppressOutput) {
 
     travelledDistance = mm_from_count(ABS(stopCount - startCount));
 
-    SERIAL_ECHOLNPAIR("Attempted travel: ", travelDistance, "mm");
-    SERIAL_ECHOLNPAIR("   Actual travel:  ", travelledDistance, "mm");
+    SERIAL_ECHOLNPGM("Attempted travel: ", travelDistance, "mm");
+    SERIAL_ECHOLNPGM("   Actual travel:  ", travelledDistance, "mm");
 
     //Calculate new axis steps per unit
     old_steps_mm = planner.settings.axis_steps_per_mm[encoderAxis];
     new_steps_mm = (old_steps_mm * travelDistance) / travelledDistance;
 
-    SERIAL_ECHOLNPAIR("Old steps/mm: ", old_steps_mm);
-    SERIAL_ECHOLNPAIR("New steps/mm: ", new_steps_mm);
+    SERIAL_ECHOLNPGM("Old steps/mm: ", old_steps_mm);
+    SERIAL_ECHOLNPGM("New steps/mm: ", new_steps_mm);
 
     //Save new value
     planner.settings.axis_steps_per_mm[encoderAxis] = new_steps_mm;
 
   if (iter > 1) {
     total /= (float)iter;
-    SERIAL_ECHOLNPAIR("Average steps/mm: ", total);
+    SERIAL_ECHOLNPGM("Average steps/mm: ", total);
   }
 
   ec = oldec;
   // First check 'new' address is not in use
   Wire.beginTransmission(I2C_ADDRESS(newaddr));
   if (!Wire.endTransmission()) {
-    SERIAL_ECHOLNPAIR("?There is already a device with that address on the I2C bus! (", newaddr, ")");
+    SERIAL_ECHOLNPGM("?There is already a device with that address on the I2C bus! (", newaddr, ")");
     return;
   }
 
   // Now check that we can find the module on the oldaddr address
   Wire.beginTransmission(I2C_ADDRESS(oldaddr));
   if (Wire.endTransmission()) {
-    SERIAL_ECHOLNPAIR("?No module detected at this address! (", oldaddr, ")");
+    SERIAL_ECHOLNPGM("?No module detected at this address! (", oldaddr, ")");
     return;
   }
 
-  SERIAL_ECHOLNPAIR("Module found at ", oldaddr, ", changing address to ", newaddr);
+  SERIAL_ECHOLNPGM("Module found at ", oldaddr, ", changing address to ", newaddr);
 
   // Change the modules address
   Wire.beginTransmission(I2C_ADDRESS(oldaddr));
   // First check there is a module
   Wire.beginTransmission(I2C_ADDRESS(address));
   if (Wire.endTransmission()) {
-    SERIAL_ECHOLNPAIR("?No module detected at this address! (", address, ")");
+    SERIAL_ECHOLNPGM("?No module detected at this address! (", address, ")");
     return;
   }
 
-  SERIAL_ECHOLNPAIR("Requesting version info from module at address ", address, ":");
+  SERIAL_ECHOLNPGM("Requesting version info from module at address ", address, ":");
 
   Wire.beginTransmission(I2C_ADDRESS(address));
   Wire.write(I2CPE_SET_REPORT_MODE);
   else if (parser.seenval('I')) {
 
     if (!parser.has_value()) {
-      SERIAL_ECHOLNPAIR("?I seen, but no index specified! [0-", I2CPE_ENCODER_CNT - 1, "]");
+      SERIAL_ECHOLNPGM("?I seen, but no index specified! [0-", I2CPE_ENCODER_CNT - 1, "]");
       return I2CPE_PARSE_ERR;
     };
 
     I2CPE_idx = parser.value_byte();
     if (I2CPE_idx >= I2CPE_ENCODER_CNT) {
-      SERIAL_ECHOLNPAIR("?Index out of range. [0-", I2CPE_ENCODER_CNT - 1, "]");
+      SERIAL_ECHOLNPGM("?Index out of range. [0-", I2CPE_ENCODER_CNT - 1, "]");
       return I2CPE_PARSE_ERR;
     }
 
     else return;
   }
 
-  SERIAL_ECHOLNPAIR("Changing module at address ", I2CPE_addr, " to address ", newAddress);
+  SERIAL_ECHOLNPGM("Changing module at address ", I2CPE_addr, " to address ", newAddress);
 
   change_module_address(I2CPE_addr, newAddress);
 }

Marlin/src/feature/encoder_i2c.h

 
     static void report_status(const int8_t idx) {
       CHECK_IDX();
-      SERIAL_ECHOLNPAIR("Encoder ", idx, ": ");
+      SERIAL_ECHOLNPGM("Encoder ", idx, ": ");
       encoders[idx].get_raw_count();
       encoders[idx].passes_test(true);
     }
 
     static void report_error_count(const int8_t idx, const AxisEnum axis) {
       CHECK_IDX();
-      SERIAL_ECHOLNPAIR("Error count on ", AS_CHAR(axis_codes[axis]), " axis is ", encoders[idx].get_error_count());
+      SERIAL_ECHOLNPGM("Error count on ", AS_CHAR(axis_codes[axis]), " axis is ", encoders[idx].get_error_count());
     }
 
     static void reset_error_count(const int8_t idx, const AxisEnum axis) {
       CHECK_IDX();
       encoders[idx].set_error_count(0);
-      SERIAL_ECHOLNPAIR("Error count on ", AS_CHAR(axis_codes[axis]), " axis has been reset.");
+      SERIAL_ECHOLNPGM("Error count on ", AS_CHAR(axis_codes[axis]), " axis has been reset.");
     }
 
     static void enable_ec(const int8_t idx, const bool enabled, const AxisEnum axis) {
       CHECK_IDX();
       encoders[idx].set_ec_enabled(enabled);
-      SERIAL_ECHOPAIR("Error correction on ", AS_CHAR(axis_codes[axis]));
+      SERIAL_ECHOPGM("Error correction on ", AS_CHAR(axis_codes[axis]));
       SERIAL_ECHO_TERNARY(encoders[idx].get_ec_enabled(), " axis is ", "en", "dis", "abled.\n");
     }
 
     static void set_ec_threshold(const int8_t idx, const float newThreshold, const AxisEnum axis) {
       CHECK_IDX();
       encoders[idx].set_ec_threshold(newThreshold);
-      SERIAL_ECHOLNPAIR("Error correct threshold for ", AS_CHAR(axis_codes[axis]), " axis set to ", newThreshold, "mm.");
+      SERIAL_ECHOLNPGM("Error correct threshold for ", AS_CHAR(axis_codes[axis]), " axis set to ", newThreshold, "mm.");
     }
 
     static void get_ec_threshold(const int8_t idx, const AxisEnum axis) {
       CHECK_IDX();
       const float threshold = encoders[idx].get_ec_threshold();
-      SERIAL_ECHOLNPAIR("Error correct threshold for ", AS_CHAR(axis_codes[axis]), " axis is ", threshold, "mm.");
+      SERIAL_ECHOLNPGM("Error correct threshold for ", AS_CHAR(axis_codes[axis]), " axis is ", threshold, "mm.");
     }
 
     static int8_t idx_from_axis(const AxisEnum axis) {

Marlin/src/feature/fwretract.cpp

   #endif
 
   /* // debugging
-    SERIAL_ECHOLNPAIR(
+    SERIAL_ECHOLNPGM(
       "retracting ", AS_DIGIT(retracting),
       " swapping ", swapping,
       " active extruder ", active_extruder
     );
     LOOP_L_N(i, EXTRUDERS) {
-      SERIAL_ECHOLNPAIR("retracted[", i, "] ", AS_DIGIT(retracted[i]));
+      SERIAL_ECHOLNPGM("retracted[", i, "] ", AS_DIGIT(retracted[i]));
       #if HAS_MULTI_EXTRUDER
-        SERIAL_ECHOLNPAIR("retracted_swap[", i, "] ", AS_DIGIT(retracted_swap[i]));
+        SERIAL_ECHOLNPGM("retracted_swap[", i, "] ", AS_DIGIT(retracted_swap[i]));
       #endif
     }
-    SERIAL_ECHOLNPAIR("current_position.z ", current_position.z);
-    SERIAL_ECHOLNPAIR("current_position.e ", current_position.e);
-    SERIAL_ECHOLNPAIR("current_hop ", current_hop);
+    SERIAL_ECHOLNPGM("current_position.z ", current_position.z);
+    SERIAL_ECHOLNPGM("current_position.e ", current_position.e);
+    SERIAL_ECHOLNPGM("current_hop ", current_hop);
   //*/
 
   const float base_retract = TERN1(RETRACT_SYNC_MIXING, (MIXING_STEPPERS))
   #endif
 
   /* // debugging
-    SERIAL_ECHOLNPAIR("retracting ", AS_DIGIT(retracting));
-    SERIAL_ECHOLNPAIR("swapping ", AS_DIGIT(swapping));
-    SERIAL_ECHOLNPAIR("active_extruder ", active_extruder);
+    SERIAL_ECHOLNPGM("retracting ", AS_DIGIT(retracting));
+    SERIAL_ECHOLNPGM("swapping ", AS_DIGIT(swapping));
+    SERIAL_ECHOLNPGM("active_extruder ", active_extruder);
     LOOP_L_N(i, EXTRUDERS) {
-      SERIAL_ECHOLNPAIR("retracted[", i, "] ", AS_DIGIT(retracted[i]));
+      SERIAL_ECHOLNPGM("retracted[", i, "] ", AS_DIGIT(retracted[i]));
       #if HAS_MULTI_EXTRUDER
-        SERIAL_ECHOLNPAIR("retracted_swap[", i, "] ", AS_DIGIT(retracted_swap[i]));
+        SERIAL_ECHOLNPGM("retracted_swap[", i, "] ", AS_DIGIT(retracted_swap[i]));
       #endif
     }
-    SERIAL_ECHOLNPAIR("current_position.z ", current_position.z);
-    SERIAL_ECHOLNPAIR("current_position.e ", current_position.e);
-    SERIAL_ECHOLNPAIR("current_hop ", current_hop);
+    SERIAL_ECHOLNPGM("current_position.z ", current_position.z);
+    SERIAL_ECHOLNPGM("current_position.e ", current_position.e);
+    SERIAL_ECHOLNPGM("current_hop ", current_hop);
   //*/
 }
 
 }
 
 void FWRetract::M207_report() {
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
       PSTR("  M207 S"), LINEAR_UNIT(settings.retract_length)
     , PSTR(" W"), LINEAR_UNIT(settings.swap_retract_length)
     , PSTR(" F"), LINEAR_UNIT(MMS_TO_MMM(settings.retract_feedrate_mm_s))
 }
 
 void FWRetract::M208_report() {
-  SERIAL_ECHOLNPAIR(
+  SERIAL_ECHOLNPGM(
       "  M208 S", LINEAR_UNIT(settings.retract_recover_extra)
     , " W", LINEAR_UNIT(settings.swap_retract_recover_extra)
     , " F", LINEAR_UNIT(MMS_TO_MMM(settings.retract_recover_feedrate_mm_s))
   }
 
   void FWRetract::M209_report() {
-    SERIAL_ECHOLNPAIR("  M209 S", AS_DIGIT(autoretract_enabled));
+    SERIAL_ECHOLNPGM("  M209 S", AS_DIGIT(autoretract_enabled));
   }
 
 #endif // FWRETRACT_AUTORETRACT

Marlin/src/feature/joystick.cpp

   void Joystick::report() {
     SERIAL_ECHOPGM("Joystick");
     #if HAS_JOY_ADC_X
-      SERIAL_ECHOPAIR_P(SP_X_STR, JOY_X(x.raw));
+      SERIAL_ECHOPGM_P(SP_X_STR, JOY_X(x.raw));
     #endif
     #if HAS_JOY_ADC_Y
-      SERIAL_ECHOPAIR_P(SP_Y_STR, JOY_Y(y.raw));
+      SERIAL_ECHOPGM_P(SP_Y_STR, JOY_Y(y.raw));
     #endif
     #if HAS_JOY_ADC_Z
-      SERIAL_ECHOPAIR_P(SP_Z_STR, JOY_Z(z.raw));
+      SERIAL_ECHOPGM_P(SP_Z_STR, JOY_Z(z.raw));
     #endif
     #if HAS_JOY_ADC_EN
       SERIAL_ECHO_TERNARY(READ(JOY_EN_PIN), " EN=", "HIGH (dis", "LOW (en", "abled)");

Marlin/src/feature/max7219.cpp

     SERIAL_ECHOPGM_P(func);
     SERIAL_CHAR('(');
     SERIAL_ECHO(v1);
-    if (v2 > 0) SERIAL_ECHOPAIR(", ", v2);
+    if (v2 > 0) SERIAL_ECHOPGM(", ", v2);
     SERIAL_CHAR(')');
     SERIAL_EOL();
   #else

Marlin/src/feature/meatpack.cpp

   #if ENABLED(MP_DEBUG)
     if (chars_decoded < 1024) {
       ++chars_decoded;
-      DEBUG_ECHOLNPAIR("RB: ", AS_CHAR(c));
+      DEBUG_ECHOLNPGM("RB: ", AS_CHAR(c));
     }
   #endif
 }

Marlin/src/feature/mixing.cpp

     cmax = _MAX(cmax, v);
     csum += v;
   }
-  //SERIAL_ECHOPAIR("Mixer::refresh_collector(", proportion, ", ", t, ") cmax=", cmax, "  csum=", csum, "  color");
+  //SERIAL_ECHOPGM("Mixer::refresh_collector(", proportion, ", ", t, ") cmax=", cmax, "  csum=", csum, "  color");
   const float inv_prop = proportion / csum;
   MIXER_STEPPER_LOOP(i) {
     c[i] = color[t][i] * inv_prop;
-    //SERIAL_ECHOPAIR(" [", t, "][", i, "] = ", color[t][i], " (", c[i], ")  ");
+    //SERIAL_ECHOPGM(" [", t, "][", i, "] = ", color[t][i], " (", c[i], ")  ");
   }
   //SERIAL_EOL();
 }

Marlin/src/feature/mixing.h

       MIXER_STEPPER_LOOP(i) mix[i] = mixer_perc_t(100.0f * color[j][i] / ctot);
 
       #ifdef MIXER_NORMALIZER_DEBUG
-        SERIAL_ECHOPAIR("V-tool ", j, " [ ");
+        SERIAL_ECHOPGM("V-tool ", j, " [ ");
         SERIAL_ECHOLIST_N(MIXING_STEPPERS, color[j][0], color[j][1], color[j][2], color[j][3], color[j][4], color[j][5]);
         SERIAL_ECHOPGM(" ] to Mix [ ");
         SERIAL_ECHOLIST_N(MIXING_STEPPERS, mix[0], mix[1], mix[2], mix[3], mix[4], mix[5]);

Marlin/src/feature/mmu/mmu2.cpp

       if (rx_ok()) {
         sscanf(rx_buffer, "%huok\n", &version);
 
-        DEBUG_ECHOLNPAIR("MMU => ", version, "\nMMU <= 'S2'");
+        DEBUG_ECHOLNPGM("MMU => ", version, "\nMMU <= 'S2'");
 
         MMU2_COMMAND("S2");   // Read Build Number
         state = -3;
       if (rx_ok()) {
         sscanf(rx_buffer, "%huok\n", &buildnr);
 
-        DEBUG_ECHOLNPAIR("MMU => ", buildnr);
+        DEBUG_ECHOLNPGM("MMU => ", buildnr);
 
         check_version();
 
       if (rx_ok()) {
         sscanf(rx_buffer, "%hhuok\n", &finda);
 
-        DEBUG_ECHOLNPAIR("MMU => ", finda, "\nMMU - ENABLED");
+        DEBUG_ECHOLNPGM("MMU => ", finda, "\nMMU - ENABLED");
 
         _enabled = true;
         state = 1;
         if (WITHIN(cmd, MMU_CMD_T0, MMU_CMD_T0 + EXTRUDERS - 1)) {
           // tool change
           int filament = cmd - MMU_CMD_T0;
-          DEBUG_ECHOLNPAIR("MMU <= T", filament);
+          DEBUG_ECHOLNPGM("MMU <= T", filament);
           tx_printf_P(PSTR("T%d\n"), filament);
           TERN_(MMU_EXTRUDER_SENSOR, mmu_idl_sens = 1); // enable idler sensor, if any
           state = 3; // wait for response
         else if (WITHIN(cmd, MMU_CMD_L0, MMU_CMD_L0 + EXTRUDERS - 1)) {
           // load
           int filament = cmd - MMU_CMD_L0;
-          DEBUG_ECHOLNPAIR("MMU <= L", filament);
+          DEBUG_ECHOLNPGM("MMU <= L", filament);
           tx_printf_P(PSTR("L%d\n"), filament);
           state = 3; // wait for response
         }
         else if (WITHIN(cmd, MMU_CMD_E0, MMU_CMD_E0 + EXTRUDERS - 1)) {
           // eject filament
           int filament = cmd - MMU_CMD_E0;
-          DEBUG_ECHOLNPAIR("MMU <= E", filament);
+          DEBUG_ECHOLNPGM("MMU <= E", filament);
           tx_printf_P(PSTR("E%d\n"), filament);
           state = 3; // wait for response
         }
         else if (WITHIN(cmd, MMU_CMD_F0, MMU_CMD_F0 + EXTRUDERS - 1)) {
           // filament type
           int filament = cmd - MMU_CMD_F0;
-          DEBUG_ECHOLNPAIR("MMU <= F", filament, " ", cmd_arg);
+          DEBUG_ECHOLNPGM("MMU <= F", filament, " ", cmd_arg);
           tx_printf_P(PSTR("F%d %d\n"), filament, cmd_arg);
           state = 3; // wait for response
         }
 
   void MMU2::mmu_continue_loading() {
     for (uint8_t i = 0; i < MMU_LOADING_ATTEMPTS_NR; i++) {
-      DEBUG_ECHOLNPAIR("Additional load attempt #", i);
+      DEBUG_ECHOLNPGM("Additional load attempt #", i);
       if (FILAMENT_PRESENT()) break;
       command(MMU_CMD_C0);
       manage_response(true, true);
     const feedRate_t fr_mm_m = pgm_read_float(&(step->feedRate));
 
     DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("E step ", es, "/", fr_mm_m);
+    DEBUG_ECHOLNPGM("E step ", es, "/", fr_mm_m);
 
     current_position.e += es;
     line_to_current_position(MMM_TO_MMS(fr_mm_m));

Marlin/src/feature/pause.cpp

  */
 static bool ensure_safe_temperature(const bool wait=true, const PauseMode mode=PAUSE_MODE_SAME) {
   DEBUG_SECTION(est, "ensure_safe_temperature", true);
-  DEBUG_ECHOLNPAIR("... wait:", wait, " mode:", mode);
+  DEBUG_ECHOLNPGM("... wait:", wait, " mode:", mode);
 
   #if ENABLED(PREVENT_COLD_EXTRUSION)
     if (!DEBUGGING(DRYRUN) && thermalManager.targetTooColdToExtrude(active_extruder))
                    DXC_ARGS
 ) {
   DEBUG_SECTION(lf, "load_filament", true);
-  DEBUG_ECHOLNPAIR("... slowlen:", slow_load_length, " fastlen:", fast_load_length, " purgelen:", purge_length, " maxbeep:", max_beep_count, " showlcd:", show_lcd, " pauseforuser:", pause_for_user, " pausemode:", mode DXC_SAY);
+  DEBUG_ECHOLNPGM("... slowlen:", slow_load_length, " fastlen:", fast_load_length, " purgelen:", purge_length, " maxbeep:", max_beep_count, " showlcd:", show_lcd, " pauseforuser:", pause_for_user, " pausemode:", mode DXC_SAY);
 
   if (!ensure_safe_temperature(false, mode)) {
     if (show_lcd) ui.pause_show_message(PAUSE_MESSAGE_STATUS, mode);
                      #endif
 ) {
   DEBUG_SECTION(uf, "unload_filament", true);
-  DEBUG_ECHOLNPAIR("... unloadlen:", unload_length, " showlcd:", show_lcd, " mode:", mode
+  DEBUG_ECHOLNPGM("... unloadlen:", unload_length, " showlcd:", show_lcd, " mode:", mode
     #if BOTH(FILAMENT_UNLOAD_ALL_EXTRUDERS, MIXING_EXTRUDER)
       , " mixmult:", mix_multiplier
     #endif
 
 bool pause_print(const_float_t retract, const xyz_pos_t &park_point, const bool show_lcd/*=false*/, const_float_t unload_length/*=0*/ DXC_ARGS) {
   DEBUG_SECTION(pp, "pause_print", true);
-  DEBUG_ECHOLNPAIR("... park.x:", park_point.x, " y:", park_point.y, " z:", park_point.z, " unloadlen:", unload_length, " showlcd:", show_lcd DXC_SAY);
+  DEBUG_ECHOLNPGM("... park.x:", park_point.x, " y:", park_point.y, " z:", park_point.z, " unloadlen:", unload_length, " showlcd:", show_lcd DXC_SAY);
 
   UNUSED(show_lcd);
 
 
   // Initial retract before move to filament change position
   if (retract && thermalManager.hotEnoughToExtrude(active_extruder)) {
-    DEBUG_ECHOLNPAIR("... retract:", retract);
+    DEBUG_ECHOLNPGM("... retract:", retract);
     unscaled_e_move(retract, PAUSE_PARK_RETRACT_FEEDRATE);
   }
 
 
 void show_continue_prompt(const bool is_reload) {
   DEBUG_SECTION(scp, "pause_print", true);
-  DEBUG_ECHOLNPAIR("... is_reload:", is_reload);
+  DEBUG_ECHOLNPGM("... is_reload:", is_reload);
 
   ui.pause_show_message(is_reload ? PAUSE_MESSAGE_INSERT : PAUSE_MESSAGE_WAITING);
   SERIAL_ECHO_START();
 
 void wait_for_confirmation(const bool is_reload/*=false*/, const int8_t max_beep_count/*=0*/ DXC_ARGS) {
   DEBUG_SECTION(wfc, "wait_for_confirmation", true);
-  DEBUG_ECHOLNPAIR("... is_reload:", is_reload, " maxbeep:", max_beep_count DXC_SAY);
+  DEBUG_ECHOLNPGM("... is_reload:", is_reload, " maxbeep:", max_beep_count DXC_SAY);
 
   bool nozzle_timed_out = false;
 
  */
 void resume_print(const_float_t slow_load_length/*=0*/, const_float_t fast_load_length/*=0*/, const_float_t purge_length/*=ADVANCED_PAUSE_PURGE_LENGTH*/, const int8_t max_beep_count/*=0*/, const celsius_t targetTemp/*=0*/ DXC_ARGS) {
   DEBUG_SECTION(rp, "resume_print", true);
-  DEBUG_ECHOLNPAIR("... slowlen:", slow_load_length, " fastlen:", fast_load_length, " purgelen:", purge_length, " maxbeep:", max_beep_count, " targetTemp:", targetTemp DXC_SAY);
+  DEBUG_ECHOLNPGM("... slowlen:", slow_load_length, " fastlen:", fast_load_length, " purgelen:", purge_length, " maxbeep:", max_beep_count, " targetTemp:", targetTemp DXC_SAY);
 
   /*
-  SERIAL_ECHOLNPAIR(
+  SERIAL_ECHOLNPGM(
     "start of resume_print()\ndual_x_carriage_mode:", dual_x_carriage_mode,
     "\nextruder_duplication_enabled:", extruder_duplication_enabled,
     "\nactive_extruder:", active_extruder,

Marlin/src/feature/powerloss.cpp

 
   void PrintJobRecovery::debug(PGM_P const prefix) {
     DEBUG_ECHOPGM_P(prefix);
-    DEBUG_ECHOLNPAIR(" Job Recovery Info...\nvalid_head:", info.valid_head, " valid_foot:", info.valid_foot);
+    DEBUG_ECHOLNPGM(" Job Recovery Info...\nvalid_head:", info.valid_head, " valid_foot:", info.valid_foot);
     if (info.valid_head) {
       if (info.valid_head == info.valid_foot) {
         DEBUG_ECHOPGM("current_position: ");
         }
         DEBUG_EOL();
 
-        DEBUG_ECHOLNPAIR("feedrate: ", info.feedrate);
+        DEBUG_ECHOLNPGM("feedrate: ", info.feedrate);
 
-        DEBUG_ECHOLNPAIR("zraise: ", info.zraise, " ", info.flag.raised ? "(before)" : "");
+        DEBUG_ECHOLNPGM("zraise: ", info.zraise, " ", info.flag.raised ? "(before)" : "");
 
         #if ENABLED(GCODE_REPEAT_MARKERS)
-          DEBUG_ECHOLNPAIR("repeat index: ", info.stored_repeat.index);
+          DEBUG_ECHOLNPGM("repeat index: ", info.stored_repeat.index);
           LOOP_L_N(i, info.stored_repeat.index)
-            DEBUG_ECHOLNPAIR("..... sdpos: ", info.stored_repeat.marker.sdpos, " count: ", info.stored_repeat.marker.counter);
+            DEBUG_ECHOLNPGM("..... sdpos: ", info.stored_repeat.marker.sdpos, " count: ", info.stored_repeat.marker.counter);
         #endif
 
         #if HAS_HOME_OFFSET
         #endif
 
         #if HAS_MULTI_EXTRUDER
-          DEBUG_ECHOLNPAIR("active_extruder: ", info.active_extruder);
+          DEBUG_ECHOLNPGM("active_extruder: ", info.active_extruder);
         #endif
 
         #if DISABLED(NO_VOLUMETRICS)
           DEBUG_ECHOPGM("filament_size:");
-          LOOP_L_N(i, EXTRUDERS) DEBUG_ECHOLNPAIR(" ", info.filament_size[i]);
+          LOOP_L_N(i, EXTRUDERS) DEBUG_ECHOLNPGM(" ", info.filament_size[i]);
           DEBUG_EOL();
         #endif
 
         #endif
 
         #if HAS_HEATED_BED
-          DEBUG_ECHOLNPAIR("target_temperature_bed: ", info.target_temperature_bed);
+          DEBUG_ECHOLNPGM("target_temperature_bed: ", info.target_temperature_bed);
         #endif
 
         #if HAS_FAN
         #endif
 
         #if HAS_LEVELING
-          DEBUG_ECHOLNPAIR("leveling: ", info.flag.leveling ? "ON" : "OFF", "  fade: ", info.fade);
+          DEBUG_ECHOLNPGM("leveling: ", info.flag.leveling ? "ON" : "OFF", "  fade: ", info.fade);
         #endif
 
         #if ENABLED(FWRETRACT)
             if (e < EXTRUDERS - 1) DEBUG_CHAR(',');
           }
           DEBUG_EOL();
-          DEBUG_ECHOLNPAIR("retract_hop: ", info.retract_hop);
+          DEBUG_ECHOLNPGM("retract_hop: ", info.retract_hop);
         #endif
 
         // Mixing extruder and gradient
         #if BOTH(MIXING_EXTRUDER, GRADIENT_MIX)
-          DEBUG_ECHOLNPAIR("gradient: ", info.gradient.enabled ? "ON" : "OFF");
+          DEBUG_ECHOLNPGM("gradient: ", info.gradient.enabled ? "ON" : "OFF");
         #endif
 
-        DEBUG_ECHOLNPAIR("sd_filename: ", info.sd_filename);
-        DEBUG_ECHOLNPAIR("sdpos: ", info.sdpos);
-        DEBUG_ECHOLNPAIR("print_job_elapsed: ", info.print_job_elapsed);
+        DEBUG_ECHOLNPGM("sd_filename: ", info.sd_filename);
+        DEBUG_ECHOLNPGM("sdpos: ", info.sdpos);
+        DEBUG_ECHOLNPGM("print_job_elapsed: ", info.print_job_elapsed);
 
         DEBUG_ECHOPGM("axis_relative:");
         if (TEST(info.axis_relative, REL_X)) DEBUG_ECHOPGM(" REL_X");
         if (TEST(info.axis_relative, E_MODE_REL)) DEBUG_ECHOPGM(" E_MODE_REL");
         DEBUG_EOL();
 
-        DEBUG_ECHOLNPAIR("flag.dryrun: ", AS_DIGIT(info.flag.dryrun));
-        DEBUG_ECHOLNPAIR("flag.allow_cold_extrusion: ", AS_DIGIT(info.flag.allow_cold_extrusion));
-        DEBUG_ECHOLNPAIR("flag.volumetric_enabled: ", AS_DIGIT(info.flag.volumetric_enabled));
+        DEBUG_ECHOLNPGM("flag.dryrun: ", AS_DIGIT(info.flag.dryrun));
+        DEBUG_ECHOLNPGM("flag.allow_cold_extrusion: ", AS_DIGIT(info.flag.allow_cold_extrusion));
+        DEBUG_ECHOLNPGM("flag.volumetric_enabled: ", AS_DIGIT(info.flag.volumetric_enabled));
       }
       else
         DEBUG_ECHOLNPGM("INVALID DATA");

Marlin/src/feature/probe_temp_comp.cpp

         #endif
         PSTR("Probe")
       );
-      SERIAL_ECHOLNPAIR(
+      SERIAL_ECHOLNPGM(
         " temp: ", temp,
         "C; Offset: ", i < 0 ? 0.0f : sensor_z_offsets[s][i], " um"
       );
   // Extrapolate
   float k, d;
   if (calib_idx < measurements) {
-    SERIAL_ECHOLNPAIR("Got ", calib_idx, " measurements. ");
+    SERIAL_ECHOLNPGM("Got ", calib_idx, " measurements. ");
     if (linear_regression(tsi, k, d)) {
       SERIAL_ECHOPGM("Applying linear extrapolation");
       calib_idx--;

Marlin/src/feature/repeat.cpp

     marker[index].sdpos = sdpos;
     marker[index].counter = count ?: -1;
     index++;
-    DEBUG_ECHOLNPAIR("Add Marker ", index, " at ", sdpos, " (", count, ")");
+    DEBUG_ECHOLNPGM("Add Marker ", index, " at ", sdpos, " (", count, ")");
   }
 }
 
   else {
     const uint8_t ind = index - 1;      // Active marker's index
     if (!marker[ind].counter) {         // Did its counter run out?
-      DEBUG_ECHOLNPAIR("Pass Marker ", index);
+      DEBUG_ECHOLNPGM("Pass Marker ", index);
       index--;                          //  Carry on. Previous marker on the next 'M808'.
     }
     else {
       card.setIndex(marker[ind].sdpos); // Loop back to the marker.
       if (marker[ind].counter > 0)      // Ignore a negative (or zero) counter.
         --marker[ind].counter;          // Decrement the counter. If zero this 'M808' will be skipped next time.
-      DEBUG_ECHOLNPAIR("Goto Marker ", index, " at ", marker[ind].sdpos, " (", marker[ind].counter, ")");
+      DEBUG_ECHOLNPGM("Goto Marker ", index, " at ", marker[ind].sdpos, " (", marker[ind].counter, ")");
     }
   }
 }
 
 void Repeat::early_parse_M808(char * const cmd) {
   if (is_command_M808(cmd)) {
-    DEBUG_ECHOLNPAIR("Parsing \"", cmd, "\"");
+    DEBUG_ECHOLNPGM("Parsing \"", cmd, "\"");
     parser.parse(cmd);
     if (parser.seen('L'))
       add_marker(card.getIndex(), parser.value_ushort());

Marlin/src/feature/runout.cpp

       char script[strlen(FILAMENT_RUNOUT_SCRIPT) + 1];
       sprintf_P(script, PSTR(FILAMENT_RUNOUT_SCRIPT), tool);
       #if ENABLED(FILAMENT_RUNOUT_SENSOR_DEBUG)
-        SERIAL_ECHOLNPAIR("Runout Command: ", script);
+        SERIAL_ECHOLNPGM("Runout Command: ", script);
       #endif
       queue.inject(script);
     #else

Marlin/src/feature/runout.h

           if (runout_flags) {
             SERIAL_ECHOPGM("Runout Sensors: ");
             LOOP_L_N(i, 8) SERIAL_ECHO('0' + TEST(runout_flags, i));
-            SERIAL_ECHOPAIR(" -> ", extruder);
+            SERIAL_ECHOPGM(" -> ", extruder);
             if (ran_out) SERIAL_ECHOPGM(" RUN OUT");
             SERIAL_EOL();
           }
             static uint8_t was_out; // = 0
             if (out != TEST(was_out, s)) {
               TBI(was_out, s);
-              SERIAL_ECHOLNPAIR_P(PSTR("Filament Sensor "), '0' + s, out ? PSTR(" OUT") : PSTR(" IN"));
+              SERIAL_ECHOLNPGM_P(PSTR("Filament Sensor "), '0' + s, out ? PSTR(" OUT") : PSTR(" IN"));
             }
           #endif
         }
           if (ELAPSED(ms, t)) {
             t = millis() + 1000UL;
             LOOP_L_N(i, NUM_RUNOUT_SENSORS)
-              SERIAL_ECHOPAIR_P(i ? PSTR(", ") : PSTR("Remaining mm: "), runout_mm_countdown[i]);
+              SERIAL_ECHOPGM_P(i ? PSTR(", ") : PSTR("Remaining mm: "), runout_mm_countdown[i]);
             SERIAL_EOL();
           }
         #endif

Marlin/src/feature/tmc_util.cpp

     SERIAL_ECHO(timestamp);
     SERIAL_ECHOPGM(": ");
     st.printLabel();
-    SERIAL_ECHOLNPAIR(" driver overtemperature warning! (", st.getMilliamps(), "mA)");
+    SERIAL_ECHOLNPGM(" driver overtemperature warning! (", st.getMilliamps(), "mA)");
   }
 
   template<typename TMC>
           st.rms_current(I_rms);
           #if ENABLED(REPORT_CURRENT_CHANGE)
             st.printLabel();
-            SERIAL_ECHOLNPAIR(" current decreased to ", I_rms);
+            SERIAL_ECHOLNPGM(" current decreased to ", I_rms);
           #endif
         }
       }

Marlin/src/feature/tmc_util.h

 template<typename TMC>
 void tmc_print_current(TMC &st) {
   st.printLabel();
-  SERIAL_ECHOLNPAIR(" driver current: ", st.getMilliamps());
+  SERIAL_ECHOLNPGM(" driver current: ", st.getMilliamps());
 }
 
 #if ENABLED(MONITOR_DRIVER_STATUS)
   template<typename TMC>
   void tmc_print_pwmthrs(TMC &st) {
     st.printLabel();
-    SERIAL_ECHOLNPAIR(" stealthChop max speed: ", st.get_pwm_thrs());
+    SERIAL_ECHOLNPGM(" stealthChop max speed: ", st.get_pwm_thrs());
   }
 #endif
 #if USE_SENSORLESS

Marlin/src/feature/twibus.cpp

 void TWIBus::echoprefix(uint8_t bytes, const char pref[], uint8_t adr) {
   SERIAL_ECHO_START();
   SERIAL_ECHOPGM_P(pref);
-  SERIAL_ECHOPAIR(": from:", adr, " bytes:", bytes, " data:");
+  SERIAL_ECHOPGM(": from:", adr, " bytes:", bytes, " data:");
 }
 
 // static

Marlin/src/gcode/bedlevel/G26.cpp

 
     if (bedtemp) {
       if (!WITHIN(bedtemp, 40, BED_MAX_TARGET)) {
-        SERIAL_ECHOLNPAIR("?Specified bed temperature not plausible (40-", BED_MAX_TARGET, "C).");
+        SERIAL_ECHOLNPGM("?Specified bed temperature not plausible (40-", BED_MAX_TARGET, "C).");
         return;
       }
       g26.bed_temp = bedtemp;

Marlin/src/gcode/bedlevel/G35.cpp

     const float z_probed_height = probe.probe_at_point(tramming_points[i], PROBE_PT_RAISE, 0, true);
 
     if (isnan(z_probed_height)) {
-      SERIAL_ECHOPAIR("G35 failed at point ", i + 1, " (");
+      SERIAL_ECHOPGM("G35 failed at point ", i + 1, " (");
       SERIAL_ECHOPGM_P((char *)pgm_read_ptr(&tramming_point_name[i]));
       SERIAL_CHAR(')');
-      SERIAL_ECHOLNPAIR_P(SP_X_STR, tramming_points[i].x, SP_Y_STR, tramming_points[i].y);
+      SERIAL_ECHOLNPGM_P(SP_X_STR, tramming_points[i].x, SP_Y_STR, tramming_points[i].y);
       err_break = true;
       break;
     }
 
     if (DEBUGGING(LEVELING)) {
-      DEBUG_ECHOPAIR("Probing point ", i + 1, " (");
+      DEBUG_ECHOPGM("Probing point ", i + 1, " (");
       DEBUG_ECHOPGM_P((char *)pgm_read_ptr(&tramming_point_name[i]));
       DEBUG_CHAR(')');
-      DEBUG_ECHOLNPAIR_P(SP_X_STR, tramming_points[i].x, SP_Y_STR, tramming_points[i].y, SP_Z_STR, z_probed_height);
+      DEBUG_ECHOLNPGM_P(SP_X_STR, tramming_points[i].x, SP_Y_STR, tramming_points[i].y, SP_Z_STR, z_probed_height);
     }
 
     z_measured[i] = z_probed_height;
 
       SERIAL_ECHOPGM("Turn ");
       SERIAL_ECHOPGM_P((char *)pgm_read_ptr(&tramming_point_name[i]));
-      SERIAL_ECHOPAIR(" ", (screw_thread & 1) == (adjust > 0) ? "CCW" : "CW", " by ", ABS(full_turns), " turns");
-      if (minutes) SERIAL_ECHOPAIR(" and ", ABS(minutes), " minutes");
-      if (ENABLED(REPORT_TRAMMING_MM)) SERIAL_ECHOPAIR(" (", -diff, "mm)");
+      SERIAL_ECHOPGM(" ", (screw_thread & 1) == (adjust > 0) ? "CCW" : "CW", " by ", ABS(full_turns), " turns");
+      if (minutes) SERIAL_ECHOPGM(" and ", ABS(minutes), " minutes");
+      if (ENABLED(REPORT_TRAMMING_MM)) SERIAL_ECHOPGM(" (", -diff, "mm)");
       SERIAL_EOL();
     }
   }

Marlin/src/gcode/bedlevel/M420.cpp

         TERN_(EXTENSIBLE_UI, ExtUI::onMeshUpdate(x, y, Z_VALUES(x, y)));
       }
       SERIAL_ECHOPGM("Simulated " STRINGIFY(GRID_MAX_POINTS_X) "x" STRINGIFY(GRID_MAX_POINTS_Y) " mesh ");
-      SERIAL_ECHOPAIR(" (", x_min);
+      SERIAL_ECHOPGM(" (", x_min);
       SERIAL_CHAR(','); SERIAL_ECHO(y_min);
-      SERIAL_ECHOPAIR(")-(", x_max);
+      SERIAL_ECHOPGM(")-(", x_max);
       SERIAL_CHAR(','); SERIAL_ECHO(y_max);
       SERIAL_ECHOLNPGM(")");
     }
 
         if (!WITHIN(storage_slot, 0, a - 1)) {
           SERIAL_ECHOLNPGM("?Invalid storage slot.");
-          SERIAL_ECHOLNPAIR("?Use 0 to ", a - 1);
+          SERIAL_ECHOLNPGM("?Use 0 to ", a - 1);
           return;
         }
 
       ubl.display_map(parser.byteval('T'));
       SERIAL_ECHOPGM("Mesh is ");
       if (!ubl.mesh_is_valid()) SERIAL_ECHOPGM("in");
-      SERIAL_ECHOLNPAIR("valid\nStorage slot: ", ubl.storage_slot);
+      SERIAL_ECHOLNPGM("valid\nStorage slot: ", ubl.storage_slot);
     }
 
   #endif // AUTO_BED_LEVELING_UBL
   report_heading_etc(forReplay, PSTR(
     TERN(MESH_BED_LEVELING, "Mesh Bed Leveling", TERN(AUTO_BED_LEVELING_UBL, "Unified Bed Leveling", "Auto Bed Leveling"))
   ));
-  SERIAL_ECHOPAIR_P(
+  SERIAL_ECHOPGM_P(
     PSTR("  M420 S"), planner.leveling_active
     #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
       , SP_Z_STR, LINEAR_UNIT(planner.z_fade_height)

Marlin/src/gcode/bedlevel/abl/G29.cpp

 
       if (!probe.good_bounds(abl.probe_position_lf, abl.probe_position_rb)) {
         if (DEBUGGING(LEVELING)) {
-          DEBUG_ECHOLNPAIR("G29 L", abl.probe_position_lf.x, " R", abl.probe_position_rb.x,
+          DEBUG_ECHOLNPGM("G29 L", abl.probe_position_lf.x, " R", abl.probe_position_rb.x,
                               " F", abl.probe_position_lf.y, " B", abl.probe_position_rb.y);
         }
         SERIAL_ECHOLNPGM("? (L,R,F,B) out of bounds.");
     if (abl.verbose_level || seenQ) {
       SERIAL_ECHOPGM("Manual G29 ");
       if (g29_in_progress)
-        SERIAL_ECHOLNPAIR("point ", _MIN(abl.abl_probe_index + 1, abl.abl_points), " of ", abl.abl_points);
+        SERIAL_ECHOLNPGM("point ", _MIN(abl.abl_probe_index + 1, abl.abl_points), " of ", abl.abl_points);
       else
         SERIAL_ECHOLNPGM("idle");
     }
         z_values[abl.meshCount.x][abl.meshCount.y] = newz;
         TERN_(EXTENSIBLE_UI, ExtUI::onMeshUpdate(abl.meshCount, newz));
 
-        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR_P(PSTR("Save X"), abl.meshCount.x, SP_Y_STR, abl.meshCount.y, SP_Z_STR, abl.measured_z + abl.Z_offset);
+        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM_P(PSTR("Save X"), abl.meshCount.x, SP_Y_STR, abl.meshCount.y, SP_Z_STR, abl.measured_z + abl.Z_offset);
 
       #endif
     }
           // Avoid probing outside the round or hexagonal area
           if (TERN0(IS_KINEMATIC, !probe.can_reach(abl.probePos))) continue;
 
-          if (abl.verbose_level) SERIAL_ECHOLNPAIR("Probing mesh point ", pt_index, "/", abl.abl_points, ".");
+          if (abl.verbose_level) SERIAL_ECHOLNPGM("Probing mesh point ", pt_index, "/", abl.abl_points, ".");
           TERN_(HAS_STATUS_MESSAGE, ui.status_printf_P(0, PSTR(S_FMT " %i/%i"), GET_TEXT(MSG_PROBING_POINT), int(pt_index), int(abl.abl_points)));
 
           abl.measured_z = faux ? 0.001f * random(-100, 101) : probe.probe_at_point(abl.probePos, raise_after, abl.verbose_level);
       // Probe at 3 arbitrary points
 
       LOOP_L_N(i, 3) {
-        if (abl.verbose_level) SERIAL_ECHOLNPAIR("Probing point ", i + 1, "/3.");
+        if (abl.verbose_level) SERIAL_ECHOLNPGM("Probing point ", i + 1, "/3.");
         TERN_(HAS_STATUS_MESSAGE, ui.status_printf_P(0, PSTR(S_FMT " %i/3"), GET_TEXT(MSG_PROBING_POINT), int(i + 1)));
 
         // Retain the last probe position
           && NEAR(current_position.y, abl.probePos.y - probe.offset_xy.y)
         ) {
           const float simple_z = current_position.z - abl.measured_z;
-          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("Probed Z", simple_z, "  Matrix Z", converted.z, "  Discrepancy ", simple_z - converted.z);
+          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("Probed Z", simple_z, "  Matrix Z", converted.z, "  Discrepancy ", simple_z - converted.z);
           converted.z = simple_z;
         }
 
     #elif ENABLED(AUTO_BED_LEVELING_BILINEAR)
 
       if (!abl.dryrun) {
-        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("G29 uncorrected Z:", current_position.z);
+        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("G29 uncorrected Z:", current_position.z);
 
         // Unapply the offset because it is going to be immediately applied
         // and cause compensation movement in Z
         const float fade_scaling_factor = TERN(ENABLE_LEVELING_FADE_HEIGHT, planner.fade_scaling_factor_for_z(current_position.z), 1);
         current_position.z -= fade_scaling_factor * bilinear_z_offset(current_position);
 
-        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR(" corrected Z:", current_position.z);
+        if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM(" corrected Z:", current_position.z);
       }
 
     #endif // ABL_PLANAR
   TERN_(HAS_BED_PROBE, probe.move_z_after_probing());
 
   #ifdef Z_PROBE_END_SCRIPT
-    if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("Z Probe End Script: ", Z_PROBE_END_SCRIPT);
+    if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("Z Probe End Script: ", Z_PROBE_END_SCRIPT);
     planner.synchronize();
     process_subcommands_now_P(PSTR(Z_PROBE_END_SCRIPT));
   #endif

Marlin/src/gcode/bedlevel/mbl/G29.cpp

       if (parser.seenval('I')) {
         ix = parser.value_int();
         if (!WITHIN(ix, 0, (GRID_MAX_POINTS_X) - 1)) {
-          SERIAL_ECHOLNPAIR("I out of range (0-", (GRID_MAX_POINTS_X) - 1, ")");
+          SERIAL_ECHOLNPGM("I out of range (0-", (GRID_MAX_POINTS_X) - 1, ")");
           return;
         }
       }
       if (parser.seenval('J')) {
         iy = parser.value_int();
         if (!WITHIN(iy, 0, (GRID_MAX_POINTS_Y) - 1)) {
-          SERIAL_ECHOLNPAIR("J out of range (0-", (GRID_MAX_POINTS_Y) - 1, ")");
+          SERIAL_ECHOLNPGM("J out of range (0-", (GRID_MAX_POINTS_Y) - 1, ")");
           return;
         }
       }
   } // switch(state)
 
   if (state == MeshNext) {
-    SERIAL_ECHOLNPAIR("MBL G29 point ", _MIN(mbl_probe_index, GRID_MAX_POINTS), " of ", GRID_MAX_POINTS);
+    SERIAL_ECHOLNPGM("MBL G29 point ", _MIN(mbl_probe_index, GRID_MAX_POINTS), " of ", GRID_MAX_POINTS);
     if (mbl_probe_index > 0) TERN_(HAS_STATUS_MESSAGE, ui.status_printf_P(0, PSTR(S_FMT " %i/%i"), GET_TEXT(MSG_PROBING_POINT), _MIN(mbl_probe_index, GRID_MAX_POINTS), int(GRID_MAX_POINTS)));
   }
 

Marlin/src/gcode/calibrate/G28.cpp

 
   #if HAS_HOMING_CURRENT
     auto debug_current = [](PGM_P const s, const int16_t a, const int16_t b) {
-      DEBUG_ECHOPGM_P(s); DEBUG_ECHOLNPAIR(" current: ", a, " -> ", b);
+      DEBUG_ECHOPGM_P(s); DEBUG_ECHOLNPGM(" current: ", a, " -> ", b);
     };
     #if HAS_CURRENT_HOME(X)
       const int16_t tmc_save_current_X = stepperX.getMilliamps();
 
     if (z_homing_height && (LINEAR_AXIS_GANG(doX, || doY, || TERN0(Z_SAFE_HOMING, doZ), || doI, || doJ, || doK))) {
       // Raise Z before homing any other axes and z is not already high enough (never lower z)
-      if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("Raise Z (before homing) by ", z_homing_height);
+      if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("Raise Z (before homing) by ", z_homing_height);
       do_z_clearance(z_homing_height);
       TERN_(BLTOUCH, bltouch.init());
     }

Marlin/src/gcode/calibrate/G33.cpp

  *  - Print the delta settings
  */
 static void print_calibration_settings(const bool end_stops, const bool tower_angles) {
-  SERIAL_ECHOPAIR(".Height:", delta_height);
+  SERIAL_ECHOPGM(".Height:", delta_height);
   if (end_stops) {
     print_signed_float(PSTR("Ex"), delta_endstop_adj.a);
     print_signed_float(PSTR("Ey"), delta_endstop_adj.b);
     print_signed_float(PSTR("Ez"), delta_endstop_adj.c);
   }
   if (end_stops && tower_angles) {
-    SERIAL_ECHOPAIR("  Radius:", delta_radius);
+    SERIAL_ECHOPGM("  Radius:", delta_radius);
     SERIAL_EOL();
     SERIAL_CHAR('.');
     SERIAL_ECHO_SP(13);
     print_signed_float(PSTR("Tz"), delta_tower_angle_trim.c);
   }
   if ((!end_stops && tower_angles) || (end_stops && !tower_angles)) { // XOR
-    SERIAL_ECHOPAIR("  Radius:", delta_radius);
+    SERIAL_ECHOPGM("  Radius:", delta_radius);
   }
   SERIAL_EOL();
 }

Marlin/src/gcode/calibrate/G34_M422.cpp

         if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> probing all positions.");
 
         const int iter = iteration + 1;
-        SERIAL_ECHOLNPAIR("\nG34 Iteration: ", iter);
+        SERIAL_ECHOLNPGM("\nG34 Iteration: ", iter);
         #if HAS_STATUS_MESSAGE
           char str[iter_str_len + 2 + 1];
           sprintf_P(str, msg_iteration, iter);
           if ((iteration == 0 || i > 0) && z_probe > current_position.z) do_blocking_move_to_z(z_probe);
 
           if (DEBUGGING(LEVELING))
-            DEBUG_ECHOLNPAIR_P(PSTR("Probing X"), z_stepper_align.xy[iprobe].x, SP_Y_STR, z_stepper_align.xy[iprobe].y);
+            DEBUG_ECHOLNPGM_P(PSTR("Probing X"), z_stepper_align.xy[iprobe].x, SP_Y_STR, z_stepper_align.xy[iprobe].y);
 
           // Probe a Z height for each stepper.
           // Probing sanity check is disabled, as it would trigger even in normal cases because
           // the next iteration of probing. This allows adjustments to be made away from the bed.
           z_measured[iprobe] = z_probed_height + Z_CLEARANCE_BETWEEN_PROBES;
 
-          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("> Z", iprobe + 1, " measured position is ", z_measured[iprobe]);
+          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> Z", iprobe + 1, " measured position is ", z_measured[iprobe]);
 
           // Remember the minimum measurement to calculate the correction later on
           z_measured_min = _MIN(z_measured_min, z_measured[iprobe]);
           linear_fit_data lfd;
           incremental_LSF_reset(&lfd);
           LOOP_L_N(i, NUM_Z_STEPPER_DRIVERS) {
-            SERIAL_ECHOLNPAIR("PROBEPT_", i, ": ", z_measured[i]);
+            SERIAL_ECHOLNPGM("PROBEPT_", i, ": ", z_measured[i]);
             incremental_LSF(&lfd, z_stepper_align.xy[i], z_measured[i]);
           }
           finish_incremental_LSF(&lfd);
             z_measured_min = _MIN(z_measured_min, z_measured[i]);
           }
 
-          SERIAL_ECHOLNPAIR(
+          SERIAL_ECHOLNPGM(
             LIST_N(DOUBLE(NUM_Z_STEPPER_DRIVERS),
               "Calculated Z1=", z_measured[0],
                         " Z2=", z_measured[1],
           );
         #endif
 
-        SERIAL_ECHOLNPAIR("\n"
+        SERIAL_ECHOLNPGM("\n"
           "Z2-Z1=", ABS(z_measured[1] - z_measured[0])
           #if TRIPLE_Z
             , " Z3-Z2=", ABS(z_measured[2] - z_measured[1])
 
             // Check for less accuracy compared to last move
             if (decreasing_accuracy(last_z_align_move[zstepper], z_align_abs)) {
-              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("> Z", zstepper + 1, " last_z_align_move = ", last_z_align_move[zstepper]);
-              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("> Z", zstepper + 1, " z_align_abs = ", z_align_abs);
+              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> Z", zstepper + 1, " last_z_align_move = ", last_z_align_move[zstepper]);
+              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> Z", zstepper + 1, " z_align_abs = ", z_align_abs);
               adjustment_reverse = !adjustment_reverse;
             }
 
           // Stop early if all measured points achieve accuracy target
           if (z_align_abs > z_auto_align_accuracy) success_break = false;
 
-          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("> Z", zstepper + 1, " corrected by ", z_align_move);
+          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> Z", zstepper + 1, " corrected by ", z_align_move);
 
           // Lock all steppers except one
           stepper.set_all_z_lock(true, zstepper);
             // Will match reversed Z steppers on dual steppers. Triple will need more work to map.
             if (adjustment_reverse) {
               z_align_move = -z_align_move;
-              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("> Z", zstepper + 1, " correction reversed to ", z_align_move);
+              if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("> Z", zstepper + 1, " correction reversed to ", z_align_move);
             }
           #endif
 
       if (err_break)
         SERIAL_ECHOLNPGM("G34 aborted.");
       else {
-        SERIAL_ECHOLNPAIR("Did ", iteration + (iteration != z_auto_align_iterations), " of ", z_auto_align_iterations);
+        SERIAL_ECHOLNPGM("Did ", iteration + (iteration != z_auto_align_iterations), " of ", z_auto_align_iterations);
         SERIAL_ECHOLNPAIR_F("Accuracy: ", z_maxdiff);
       }
 
   report_heading(forReplay, PSTR(STR_Z_AUTO_ALIGN));
   LOOP_L_N(i, NUM_Z_STEPPER_DRIVERS) {
     report_echo_start(forReplay);
-    SERIAL_ECHOLNPAIR_P(
+    SERIAL_ECHOLNPGM_P(
       PSTR("  M422 S"), i + 1,
       SP_X_STR, z_stepper_align.xy[i].x,
       SP_Y_STR, z_stepper_align.xy[i].y
   #if ENABLED(Z_STEPPER_ALIGN_KNOWN_STEPPER_POSITIONS)
     LOOP_L_N(i, NUM_Z_STEPPER_DRIVERS) {
       report_echo_start(forReplay);
-      SERIAL_ECHOLNPAIR_P(
+      SERIAL_ECHOLNPGM_P(
         PSTR("  M422 W"), i + 1,
         SP_X_STR, z_stepper_align.stepper_xy[i].x,
         SP_Y_STR, z_stepper_align.stepper_xy[i].y

Marlin/src/gcode/calibrate/G425.cpp

   inline void report_measured_faces(const measurements_t &m) {
     SERIAL_ECHOLNPGM("Sides:");
     #if HAS_Z_AXIS && AXIS_CAN_CALIBRATE(Z)
-      SERIAL_ECHOLNPAIR("  Top: ", m.obj_side[TOP]);
+      SERIAL_ECHOLNPGM("  Top: ", m.obj_side[TOP]);
     #endif
     #if ENABLED(CALIBRATION_MEASURE_LEFT)
-      SERIAL_ECHOLNPAIR("  Left: ", m.obj_side[LEFT]);
+      SERIAL_ECHOLNPGM("  Left: ", m.obj_side[LEFT]);
     #endif
     #if ENABLED(CALIBRATION_MEASURE_RIGHT)
-      SERIAL_ECHOLNPAIR("  Right: ", m.obj_side[RIGHT]);
+      SERIAL_ECHOLNPGM("  Right: ", m.obj_side[RIGHT]);
     #endif
     #if HAS_Y_AXIS
       #if ENABLED(CALIBRATION_MEASURE_FRONT)
-        SERIAL_ECHOLNPAIR("  Front: ", m.obj_side[FRONT]);
+        SERIAL_ECHOLNPGM("  Front: ", m.obj_side[FRONT]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_BACK)
-        SERIAL_ECHOLNPAIR("  Back: ", m.obj_side[BACK]);
+        SERIAL_ECHOLNPGM("  Back: ", m.obj_side[BACK]);
       #endif
     #endif
     #if LINEAR_AXES >= 4
       #if ENABLED(CALIBRATION_MEASURE_IMIN)
-        SERIAL_ECHOLNPAIR("  " STR_I_MIN ": ", m.obj_side[IMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_I_MIN ": ", m.obj_side[IMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_IMAX)
-        SERIAL_ECHOLNPAIR("  " STR_I_MAX ": ", m.obj_side[IMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_I_MAX ": ", m.obj_side[IMAXIMUM]);
       #endif
     #endif
     #if LINEAR_AXES >= 5
       #if ENABLED(CALIBRATION_MEASURE_JMIN)
-        SERIAL_ECHOLNPAIR("  " STR_J_MIN ": ", m.obj_side[JMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_J_MIN ": ", m.obj_side[JMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_JMAX)
-        SERIAL_ECHOLNPAIR("  " STR_J_MAX ": ", m.obj_side[JMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_J_MAX ": ", m.obj_side[JMAXIMUM]);
       #endif
     #endif
     #if LINEAR_AXES >= 6
       #if ENABLED(CALIBRATION_MEASURE_KMIN)
-        SERIAL_ECHOLNPAIR("  " STR_K_MIN ": ", m.obj_side[KMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_K_MIN ": ", m.obj_side[KMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_KMAX)
-        SERIAL_ECHOLNPAIR("  " STR_K_MAX ": ", m.obj_side[KMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_K_MAX ": ", m.obj_side[KMAXIMUM]);
       #endif
     #endif
     SERIAL_EOL();
   inline void report_measured_center(const measurements_t &m) {
     SERIAL_ECHOLNPGM("Center:");
     #if HAS_X_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_X_STR, m.obj_center.x);
+      SERIAL_ECHOLNPGM_P(SP_X_STR, m.obj_center.x);
     #endif
     #if HAS_Y_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_Y_STR, m.obj_center.y);
+      SERIAL_ECHOLNPGM_P(SP_Y_STR, m.obj_center.y);
     #endif
-    SERIAL_ECHOLNPAIR_P(SP_Z_STR, m.obj_center.z);
+    SERIAL_ECHOLNPGM_P(SP_Z_STR, m.obj_center.z);
     #if HAS_I_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_I_STR, m.obj_center.i);
+      SERIAL_ECHOLNPGM_P(SP_I_STR, m.obj_center.i);
     #endif
     #if HAS_J_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_J_STR, m.obj_center.j);
+      SERIAL_ECHOLNPGM_P(SP_J_STR, m.obj_center.j);
     #endif
     #if HAS_K_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_K_STR, m.obj_center.k);
+      SERIAL_ECHOLNPGM_P(SP_K_STR, m.obj_center.k);
     #endif
     SERIAL_EOL();
   }
     SERIAL_ECHOLNPGM("Backlash:");
     #if AXIS_CAN_CALIBRATE(X)
       #if ENABLED(CALIBRATION_MEASURE_LEFT)
-        SERIAL_ECHOLNPAIR("  Left: ", m.backlash[LEFT]);
+        SERIAL_ECHOLNPGM("  Left: ", m.backlash[LEFT]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_RIGHT)
-        SERIAL_ECHOLNPAIR("  Right: ", m.backlash[RIGHT]);
+        SERIAL_ECHOLNPGM("  Right: ", m.backlash[RIGHT]);
       #endif
     #endif
     #if HAS_Y_AXIS && AXIS_CAN_CALIBRATE(Y)
       #if ENABLED(CALIBRATION_MEASURE_FRONT)
-        SERIAL_ECHOLNPAIR("  Front: ", m.backlash[FRONT]);
+        SERIAL_ECHOLNPGM("  Front: ", m.backlash[FRONT]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_BACK)
-        SERIAL_ECHOLNPAIR("  Back: ", m.backlash[BACK]);
+        SERIAL_ECHOLNPGM("  Back: ", m.backlash[BACK]);
       #endif
     #endif
     #if HAS_Z_AXIS && AXIS_CAN_CALIBRATE(Z)
-      SERIAL_ECHOLNPAIR("  Top: ", m.backlash[TOP]);
+      SERIAL_ECHOLNPGM("  Top: ", m.backlash[TOP]);
     #endif
     #if LINEAR_AXES >= 4 && AXIS_CAN_CALIBRATE(I)
       #if ENABLED(CALIBRATION_MEASURE_IMIN)
-        SERIAL_ECHOLNPAIR("  " STR_I_MIN ": ", m.backlash[IMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_I_MIN ": ", m.backlash[IMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_IMAX)
-        SERIAL_ECHOLNPAIR("  " STR_I_MAX ": ", m.backlash[IMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_I_MAX ": ", m.backlash[IMAXIMUM]);
       #endif
     #endif
     #if LINEAR_AXES >= 5 && AXIS_CAN_CALIBRATE(J)
       #if ENABLED(CALIBRATION_MEASURE_JMIN)
-        SERIAL_ECHOLNPAIR("  " STR_J_MIN ": ", m.backlash[JMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_J_MIN ": ", m.backlash[JMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_JMAX)
-        SERIAL_ECHOLNPAIR("  " STR_J_MAX ": ", m.backlash[JMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_J_MAX ": ", m.backlash[JMAXIMUM]);
       #endif
     #endif
     #if LINEAR_AXES >= 6 && AXIS_CAN_CALIBRATE(K)
       #if ENABLED(CALIBRATION_MEASURE_KMIN)
-        SERIAL_ECHOLNPAIR("  " STR_K_MIN ": ", m.backlash[KMINIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_K_MIN ": ", m.backlash[KMINIMUM]);
       #endif
       #if ENABLED(CALIBRATION_MEASURE_KMAX)
-        SERIAL_ECHOLNPAIR("  " STR_K_MAX ": ", m.backlash[KMAXIMUM]);
+        SERIAL_ECHOLNPGM("  " STR_K_MAX ": ", m.backlash[KMAXIMUM]);
       #endif
     #endif
     SERIAL_EOL();
     SERIAL_ECHO(active_extruder);
     SERIAL_ECHOLNPGM(" Positional Error:");
     #if HAS_X_CENTER && AXIS_CAN_CALIBRATE(X)
-      SERIAL_ECHOLNPAIR_P(SP_X_STR, m.pos_error.x);
+      SERIAL_ECHOLNPGM_P(SP_X_STR, m.pos_error.x);
     #endif
     #if HAS_Y_CENTER && AXIS_CAN_CALIBRATE(Y)
-      SERIAL_ECHOLNPAIR_P(SP_Y_STR, m.pos_error.y);
+      SERIAL_ECHOLNPGM_P(SP_Y_STR, m.pos_error.y);
     #endif
     #if HAS_Z_AXIS && AXIS_CAN_CALIBRATE(Z)
-      SERIAL_ECHOLNPAIR_P(SP_Z_STR, m.pos_error.z);
+      SERIAL_ECHOLNPGM_P(SP_Z_STR, m.pos_error.z);
     #endif
     #if HAS_I_CENTER && AXIS_CAN_CALIBRATE(I)
-      SERIAL_ECHOLNPAIR_P(SP_I_STR, m.pos_error.i);
+      SERIAL_ECHOLNPGM_P(SP_I_STR, m.pos_error.i);
     #endif
     #if HAS_J_CENTER && AXIS_CAN_CALIBRATE(J)
-      SERIAL_ECHOLNPAIR_P(SP_J_STR, m.pos_error.j);
+      SERIAL_ECHOLNPGM_P(SP_J_STR, m.pos_error.j);
     #endif
     #if HAS_K_CENTER && AXIS_CAN_CALIBRATE(K)
-      SERIAL_ECHOLNPAIR_P(SP_Z_STR, m.pos_error.z);
+      SERIAL_ECHOLNPGM_P(SP_Z_STR, m.pos_error.z);
     #endif
     SERIAL_EOL();
   }
   inline void report_measured_nozzle_dimensions(const measurements_t &m) {
     SERIAL_ECHOLNPGM("Nozzle Tip Outer Dimensions:");
     #if HAS_X_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_X_STR, m.nozzle_outer_dimension.x);
+      SERIAL_ECHOLNPGM_P(SP_X_STR, m.nozzle_outer_dimension.x);
     #endif
     #if HAS_Y_CENTER
-      SERIAL_ECHOLNPAIR_P(SP_Y_STR, m.nozzle_outer_dimension.y);
+      SERIAL_ECHOLNPGM_P(SP_Y_STR, m.nozzle_outer_dimension.y);
     #endif
     SERIAL_EOL();
     UNUSED(m);
     //
     inline void report_hotend_offsets() {
       LOOP_S_L_N(e, 1, HOTENDS)
-        SERIAL_ECHOLNPAIR_P(PSTR("T"), e, PSTR(" Hotend Offset X"), hotend_offset[e].x, SP_Y_STR, hotend_offset[e].y, SP_Z_STR, hotend_offset[e].z);
+        SERIAL_ECHOLNPGM_P(PSTR("T"), e, PSTR(" Hotend Offset X"), hotend_offset[e].x, SP_Y_STR, hotend_offset[e].y, SP_Z_STR, hotend_offset[e].z);
     }
   #endif
 

Marlin/src/gcode/calibrate/G76_M192_M871.cpp

   millis_t next_temp_report = millis() + 1000;
 
   auto report_targets = [&](const celsius_t tb, const celsius_t tp) {
-    SERIAL_ECHOLNPAIR("Target Bed:", tb, " Probe:", tp);
+    SERIAL_ECHOLNPGM("Target Bed:", tb, " Probe:", tp);
   };
 
   if (do_bed_cal) {
       if (isnan(measured_z) || target_bed > (BED_MAX_TARGET)) break;
     }
 
-    SERIAL_ECHOLNPAIR("Retrieved measurements: ", temp_comp.get_index());
+    SERIAL_ECHOLNPGM("Retrieved measurements: ", temp_comp.get_index());
     if (temp_comp.finish_calibration(TSI_BED)) {
       say_successfully_calibrated();
       SERIAL_ECHOLNPGM(" bed.");
       do_blocking_move_to(noz_pos_xyz);
 
       say_waiting_for_probe_heating();
-      SERIAL_ECHOLNPAIR(" Bed:", target_bed, " Probe:", target_probe);
+      SERIAL_ECHOLNPGM(" Bed:", target_bed, " Probe:", target_probe);
       const millis_t probe_timeout_ms = millis() + SEC_TO_MS(900UL);
       while (thermalManager.degProbe() < target_probe) {
         if (report_temps(next_temp_report, probe_timeout_ms)) {
       if (isnan(measured_z) || target_probe > cali_info_init[TSI_PROBE].end_temp) break;
     }
 
-    SERIAL_ECHOLNPAIR("Retrieved measurements: ", temp_comp.get_index());
+    SERIAL_ECHOLNPGM("Retrieved measurements: ", temp_comp.get_index());
     if (temp_comp.finish_calibration(TSI_PROBE))
       say_successfully_calibrated();
     else
                                 TSI_PROBE
                               );
     if (idx > 0 && temp_comp.set_offset(mod, idx - 1, offset_val))
-      SERIAL_ECHOLNPAIR("Set value: ", offset_val);
+      SERIAL_ECHOLNPGM("Set value: ", offset_val);
     else
       SERIAL_ECHOLNPGM("!Invalid index. Failed to set value (note: value at index 0 is constant).");
 

Marlin/src/gcode/calibrate/M100.cpp

   char *start_free_memory = free_memory_start, *end_free_memory = free_memory_end;
   int n = end_free_memory - start_free_memory;
 
-  SERIAL_ECHOLNPAIR("\nfmc() n=", n,
+  SERIAL_ECHOLNPGM("\nfmc() n=", n,
                     "\nfree_memory_start=", hex_address(free_memory_start),
                     "  end=", hex_address(end_free_memory));
 
     if (start_free_memory[i] == TEST_BYTE) {
       int32_t j = count_test_bytes(start_free_memory + i);
       if (j > 8) {
-        //SERIAL_ECHOPAIR("Found ", j);
-        //SERIAL_ECHOLNPAIR(" bytes free at ", hex_address(start_free_memory + i));
+        //SERIAL_ECHOPGM("Found ", j);
+        //SERIAL_ECHOLNPGM(" bytes free at ", hex_address(start_free_memory + i));
         i += j;
         block_cnt++;
-        SERIAL_ECHOLNPAIR(" (", block_cnt, ") found=", j);
+        SERIAL_ECHOLNPGM(" (", block_cnt, ") found=", j);
       }
     }
   }
-  SERIAL_ECHOPAIR("  block_found=", block_cnt);
+  SERIAL_ECHOPGM("  block_found=", block_cnt);
 
   if (block_cnt != 1)
     SERIAL_ECHOLNPGM("\nMemory Corruption detected in free memory area.");
     if (*addr == TEST_BYTE) {
       const int32_t j = count_test_bytes(addr);
       if (j > 8) {
-        SERIAL_ECHOLNPAIR("Found ", j, " bytes free at ", hex_address(addr));
+        SERIAL_ECHOLNPGM("Found ", j, " bytes free at ", hex_address(addr));
         if (j > max_cnt) {
           max_cnt  = j;
           max_addr = addr;
       }
     }
   }
-  if (block_cnt > 1) SERIAL_ECHOLNPAIR(
+  if (block_cnt > 1) SERIAL_ECHOLNPGM(
     "\nMemory Corruption detected in free memory area."
     "\nLargest free block is ", max_cnt, " bytes at ", hex_address(max_addr)
   );
-  SERIAL_ECHOLNPAIR("check_for_free_memory_corruption() = ", check_for_free_memory_corruption(PSTR("M100 F ")));
+  SERIAL_ECHOLNPGM("check_for_free_memory_corruption() = ", check_for_free_memory_corruption(PSTR("M100 F ")));
 }
 
 #if ENABLED(M100_FREE_MEMORY_CORRUPTOR)
     for (uint32_t i = 1; i <= size; i++) {
       char * const addr = start_free_memory + i * j;
       *addr = i;
-      SERIAL_ECHOPAIR("\nCorrupting address: ", hex_address(addr));
+      SERIAL_ECHOPGM("\nCorrupting address: ", hex_address(addr));
     }
     SERIAL_EOL();
   }
 
   for (int32_t i = 0; i < size; i++) {
     if (start_free_memory[i] != TEST_BYTE) {
-      SERIAL_ECHOPAIR("? address : ", hex_address(start_free_memory + i));
-      SERIAL_ECHOLNPAIR("=", hex_byte(start_free_memory[i]));
+      SERIAL_ECHOPGM("? address : ", hex_address(start_free_memory + i));
+      SERIAL_ECHOLNPGM("=", hex_byte(start_free_memory[i]));
       SERIAL_EOL();
     }
   }
 void GcodeSuite::M100() {
   char *sp = top_of_stack();
   if (!free_memory_end) free_memory_end = sp - MEMORY_END_CORRECTION;
-                  SERIAL_ECHOPAIR("\nbss_end               : ", hex_address(end_bss));
-  if (heaplimit)  SERIAL_ECHOPAIR("\n__heaplimit           : ", hex_address(heaplimit));
-                  SERIAL_ECHOPAIR("\nfree_memory_start     : ", hex_address(free_memory_start));
-  if (stacklimit) SERIAL_ECHOPAIR("\n__stacklimit          : ", hex_address(stacklimit));
-                  SERIAL_ECHOPAIR("\nfree_memory_end       : ", hex_address(free_memory_end));
+                  SERIAL_ECHOPGM("\nbss_end               : ", hex_address(end_bss));
+  if (heaplimit)  SERIAL_ECHOPGM("\n__heaplimit           : ", hex_address(heaplimit));
+                  SERIAL_ECHOPGM("\nfree_memory_start     : ", hex_address(free_memory_start));
+  if (stacklimit) SERIAL_ECHOPGM("\n__stacklimit          : ", hex_address(stacklimit));
+                  SERIAL_ECHOPGM("\nfree_memory_end       : ", hex_address(free_memory_end));
   if (MEMORY_END_CORRECTION)
-                  SERIAL_ECHOPAIR("\nMEMORY_END_CORRECTION : ", MEMORY_END_CORRECTION);
-                  SERIAL_ECHOLNPAIR("\nStack Pointer       : ", hex_address(sp));
+                  SERIAL_ECHOPGM("\nMEMORY_END_CORRECTION : ", MEMORY_END_CORRECTION);
+                  SERIAL_ECHOLNPGM("\nStack Pointer       : ", hex_address(sp));
 
   // Always init on the first invocation of M100
   static bool m100_not_initialized = true;

Marlin/src/gcode/calibrate/M425.cpp

     SERIAL_ECHOPGM("Backlash Correction ");
     if (!backlash.correction) SERIAL_ECHOPGM("in");
     SERIAL_ECHOLNPGM("active:");
-    SERIAL_ECHOLNPAIR("  Correction Amount/Fade-out:     F", backlash.get_correction(), " (F1.0 = full, F0.0 = none)");
+    SERIAL_ECHOLNPGM("  Correction Amount/Fade-out:     F", backlash.get_correction(), " (F1.0 = full, F0.0 = none)");
     SERIAL_ECHOPGM("  Backlash Distance (mm):        ");
     LOOP_LINEAR_AXES(a) if (axis_can_calibrate(a)) {
       SERIAL_CHAR(' ', AXIS_CHAR(a));
     }
 
     #ifdef BACKLASH_SMOOTHING_MM
-      SERIAL_ECHOLNPAIR("  Smoothing (mm):                 S", backlash.smoothing_mm);
+      SERIAL_ECHOLNPGM("  Smoothing (mm):                 S", backlash.smoothing_mm);
     #endif
 
     #if ENABLED(MEASURE_BACKLASH_WHEN_PROBING)
 
 void GcodeSuite::M425_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_BACKLASH_COMPENSATION));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
     PSTR("  M425 F"), backlash.get_correction()
     #ifdef BACKLASH_SMOOTHING_MM
       , PSTR(" S"), LINEAR_UNIT(backlash.smoothing_mm)

Marlin/src/gcode/calibrate/M48.cpp

           #endif
         );
         if (verbose_level > 3) {
-          SERIAL_ECHOPAIR("Start radius:", radius, " angle:", angle, " dir:");
+          SERIAL_ECHOPGM("Start radius:", radius, " angle:", angle, " dir:");
           if (dir > 0) SERIAL_CHAR('C');
           SERIAL_ECHOLNPGM("CW");
         }
             while (!probe.can_reach(next_pos)) {
               next_pos *= 0.8f;
               if (verbose_level > 3)
-                SERIAL_ECHOLNPAIR_P(PSTR("Moving inward: X"), next_pos.x, SP_Y_STR, next_pos.y);
+                SERIAL_ECHOLNPGM_P(PSTR("Moving inward: X"), next_pos.x, SP_Y_STR, next_pos.y);
             }
           #elif HAS_ENDSTOPS
             // For a rectangular bed just keep the probe in bounds
           #endif
 
           if (verbose_level > 3)
-            SERIAL_ECHOLNPAIR_P(PSTR("Going to: X"), next_pos.x, SP_Y_STR, next_pos.y);
+            SERIAL_ECHOLNPGM_P(PSTR("Going to: X"), next_pos.x, SP_Y_STR, next_pos.y);
 
           do_blocking_move_to_xy(next_pos);
         } // n_legs loop
 
       if (verbose_level > 1) {
         SERIAL_ECHO(n + 1);
-        SERIAL_ECHOPAIR(" of ", n_samples);
+        SERIAL_ECHOPGM(" of ", n_samples);
         SERIAL_ECHOPAIR_F(": z: ", pz, 3);
         SERIAL_CHAR(' ');
         dev_report(verbose_level > 2, mean, sigma, min, max);

Marlin/src/gcode/calibrate/M665.cpp

 
   void GcodeSuite::M665_report(const bool forReplay/*=true*/) {
     report_heading_etc(forReplay, PSTR(STR_DELTA_SETTINGS));
-    SERIAL_ECHOLNPAIR_P(
+    SERIAL_ECHOLNPGM_P(
         PSTR("  M665 L"), LINEAR_UNIT(delta_diagonal_rod)
       , PSTR(" R"), LINEAR_UNIT(delta_radius)
       , PSTR(" H"), LINEAR_UNIT(delta_height)
 
   void GcodeSuite::M665_report(const bool forReplay/*=true*/) {
     report_heading_etc(forReplay, PSTR(STR_SCARA_SETTINGS " (" STR_SCARA_S TERN_(HAS_SCARA_OFFSET, " " STR_SCARA_P_T_Z) ")"));
-    SERIAL_ECHOLNPAIR_P(
+    SERIAL_ECHOLNPGM_P(
       PSTR("  M665 S"), segments_per_second
       #if HAS_SCARA_OFFSET
         , SP_P_STR, scara_home_offset.a

Marlin/src/gcode/calibrate/M666.cpp

           is_err = true;
         else {
           delta_endstop_adj[i] = v;
-          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("delta_endstop_adj[", AS_CHAR(AXIS_CHAR(i)), "] = ", v);
+          if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("delta_endstop_adj[", AS_CHAR(AXIS_CHAR(i)), "] = ", v);
         }
       }
     }
-    if (is_err) SERIAL_ECHOLNPAIR("?M666 offsets must be <= 0");
+    if (is_err) SERIAL_ECHOLNPGM("?M666 offsets must be <= 0");
     if (!is_set) M666_report();
   }
 
   void GcodeSuite::M666_report(const bool forReplay/*=true*/) {
     report_heading_etc(forReplay, PSTR(STR_ENDSTOP_ADJUSTMENT));
-    SERIAL_ECHOLNPAIR_P(
+    SERIAL_ECHOLNPGM_P(
         PSTR("  M666 X"), LINEAR_UNIT(delta_endstop_adj.a)
       , SP_Y_STR, LINEAR_UNIT(delta_endstop_adj.b)
       , SP_Z_STR, LINEAR_UNIT(delta_endstop_adj.c)
     report_heading_etc(forReplay, PSTR(STR_ENDSTOP_ADJUSTMENT));
     SERIAL_ECHOPGM("  M666");
     #if ENABLED(X_DUAL_ENDSTOPS)
-      SERIAL_ECHOLNPAIR_P(SP_X_STR, LINEAR_UNIT(endstops.x2_endstop_adj));
+      SERIAL_ECHOLNPGM_P(SP_X_STR, LINEAR_UNIT(endstops.x2_endstop_adj));
     #endif
     #if ENABLED(Y_DUAL_ENDSTOPS)
-      SERIAL_ECHOLNPAIR_P(SP_Y_STR, LINEAR_UNIT(endstops.y2_endstop_adj));
+      SERIAL_ECHOLNPGM_P(SP_Y_STR, LINEAR_UNIT(endstops.y2_endstop_adj));
     #endif
     #if ENABLED(Z_MULTI_ENDSTOPS)
       #if NUM_Z_STEPPER_DRIVERS >= 3
-        SERIAL_ECHOPAIR(" S2 Z", LINEAR_UNIT(endstops.z3_endstop_adj));
+        SERIAL_ECHOPGM(" S2 Z", LINEAR_UNIT(endstops.z3_endstop_adj));
         report_echo_start(forReplay);
-        SERIAL_ECHOPAIR("  M666 S3 Z", LINEAR_UNIT(endstops.z3_endstop_adj));
+        SERIAL_ECHOPGM("  M666 S3 Z", LINEAR_UNIT(endstops.z3_endstop_adj));
         #if NUM_Z_STEPPER_DRIVERS >= 4
           report_echo_start(forReplay);
-          SERIAL_ECHOPAIR("  M666 S4 Z", LINEAR_UNIT(endstops.z4_endstop_adj));
+          SERIAL_ECHOPGM("  M666 S4 Z", LINEAR_UNIT(endstops.z4_endstop_adj));
         #endif
       #else
-        SERIAL_ECHOLNPAIR_P(SP_Z_STR, LINEAR_UNIT(endstops.z2_endstop_adj));
+        SERIAL_ECHOLNPGM_P(SP_Z_STR, LINEAR_UNIT(endstops.z2_endstop_adj));
       #endif
     #endif
   }

Marlin/src/gcode/config/M200-M205.cpp

 
     #if EXTRUDERS == 1
     {
-      SERIAL_ECHOLNPAIR(
+      SERIAL_ECHOLNPGM(
         "  M200 S", parser.volumetric_enabled, " D", LINEAR_UNIT(planner.filament_size[0])
         #if ENABLED(VOLUMETRIC_EXTRUDER_LIMIT)
           , " L", LINEAR_UNIT(planner.volumetric_extruder_limit[0])
       );
     }
     #else
-      SERIAL_ECHOLNPAIR("  M200 S", parser.volumetric_enabled);
+      SERIAL_ECHOLNPGM("  M200 S", parser.volumetric_enabled);
       LOOP_L_N(i, EXTRUDERS) {
         report_echo_start(forReplay);
-        SERIAL_ECHOLNPAIR(
+        SERIAL_ECHOLNPGM(
           "  M200 T", i, " D", LINEAR_UNIT(planner.filament_size[i])
           #if ENABLED(VOLUMETRIC_EXTRUDER_LIMIT)
             , " L", LINEAR_UNIT(planner.volumetric_extruder_limit[i])
 
 void GcodeSuite::M201_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_MAX_ACCELERATION));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
     LIST_N(DOUBLE(LINEAR_AXES),
       PSTR("  M201 X"), LINEAR_UNIT(planner.settings.max_acceleration_mm_per_s2[X_AXIS]),
       SP_Y_STR, LINEAR_UNIT(planner.settings.max_acceleration_mm_per_s2[Y_AXIS]),
   #if ENABLED(DISTINCT_E_FACTORS)
     LOOP_L_N(i, E_STEPPERS) {
       report_echo_start(forReplay);
-      SERIAL_ECHOLNPAIR_P(
+      SERIAL_ECHOLNPGM_P(
           PSTR("  M201 T"), i
         , SP_E_STR, VOLUMETRIC_UNIT(planner.settings.max_acceleration_mm_per_s2[E_AXIS_N(i)])
       );
 
 void GcodeSuite::M203_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_MAX_FEEDRATES));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
     LIST_N(DOUBLE(LINEAR_AXES),
       PSTR("  M203 X"), LINEAR_UNIT(planner.settings.max_feedrate_mm_s[X_AXIS]),
       SP_Y_STR, LINEAR_UNIT(planner.settings.max_feedrate_mm_s[Y_AXIS]),
   #if ENABLED(DISTINCT_E_FACTORS)
     LOOP_L_N(i, E_STEPPERS) {
       SERIAL_ECHO_START();
-      SERIAL_ECHOLNPAIR_P(
+      SERIAL_ECHOLNPGM_P(
           PSTR("  M203 T"), i
         , SP_E_STR, VOLUMETRIC_UNIT(planner.settings.max_feedrate_mm_s[E_AXIS_N(i)])
       );
 
 void GcodeSuite::M204_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_ACCELERATION_P_R_T));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
       PSTR("  M204 P"), LINEAR_UNIT(planner.settings.acceleration)
     , PSTR(" R"), LINEAR_UNIT(planner.settings.retract_acceleration)
     , SP_T_STR, LINEAR_UNIT(planner.settings.travel_acceleration)
     TERN_(HAS_CLASSIC_E_JERK, " E<max_e_jerk>")
     ")"
   ));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
       PSTR("  M205 B"), LINEAR_UNIT(planner.settings.min_segment_time_us)
     , PSTR(" S"), LINEAR_UNIT(planner.settings.min_feedrate_mm_s)
     , SP_T_STR, LINEAR_UNIT(planner.settings.min_travel_feedrate_mm_s)

Marlin/src/gcode/config/M217.cpp

   SERIAL_ECHOPGM("  M217");
 
   #if ENABLED(TOOLCHANGE_FILAMENT_SWAP)
-    SERIAL_ECHOPAIR(" S", LINEAR_UNIT(toolchange_settings.swap_length));
-    SERIAL_ECHOPAIR_P(SP_B_STR, LINEAR_UNIT(toolchange_settings.extra_resume),
+    SERIAL_ECHOPGM(" S", LINEAR_UNIT(toolchange_settings.swap_length));
+    SERIAL_ECHOPGM_P(SP_B_STR, LINEAR_UNIT(toolchange_settings.extra_resume),
                       SP_E_STR, LINEAR_UNIT(toolchange_settings.extra_prime),
                       SP_P_STR, LINEAR_UNIT(toolchange_settings.prime_speed));
-    SERIAL_ECHOPAIR(" R", LINEAR_UNIT(toolchange_settings.retract_speed),
+    SERIAL_ECHOPGM(" R", LINEAR_UNIT(toolchange_settings.retract_speed),
                     " U", LINEAR_UNIT(toolchange_settings.unretract_speed),
                     " F", toolchange_settings.fan_speed,
                     " G", toolchange_settings.fan_time);
 
     #if ENABLED(TOOLCHANGE_MIGRATION_FEATURE)
-      SERIAL_ECHOPAIR(" A", migration.automode);
-      SERIAL_ECHOPAIR(" L", LINEAR_UNIT(migration.last));
+      SERIAL_ECHOPGM(" A", migration.automode);
+      SERIAL_ECHOPGM(" L", LINEAR_UNIT(migration.last));
     #endif
 
     #if ENABLED(TOOLCHANGE_PARK)
-      SERIAL_ECHOPAIR(" W", LINEAR_UNIT(toolchange_settings.enable_park));
-      SERIAL_ECHOPAIR_P(SP_X_STR, LINEAR_UNIT(toolchange_settings.change_point.x));
-      SERIAL_ECHOPAIR_P(SP_Y_STR, LINEAR_UNIT(toolchange_settings.change_point.y));
+      SERIAL_ECHOPGM(" W", LINEAR_UNIT(toolchange_settings.enable_park));
+      SERIAL_ECHOPGM_P(SP_X_STR, LINEAR_UNIT(toolchange_settings.change_point.x));
+      SERIAL_ECHOPGM_P(SP_Y_STR, LINEAR_UNIT(toolchange_settings.change_point.y));
     #endif
 
     #if ENABLED(TOOLCHANGE_FS_PRIME_FIRST_USED)
-      SERIAL_ECHOPAIR(" V", LINEAR_UNIT(enable_first_prime));
+      SERIAL_ECHOPGM(" V", LINEAR_UNIT(enable_first_prime));
     #endif
 
   #endif
 
-  SERIAL_ECHOLNPAIR_P(SP_Z_STR, LINEAR_UNIT(toolchange_settings.z_raise));
+  SERIAL_ECHOLNPGM_P(SP_Z_STR, LINEAR_UNIT(toolchange_settings.z_raise));
 }
 
 #endif // HAS_MULTI_EXTRUDER

Marlin/src/gcode/config/M218.cpp

   report_heading_etc(forReplay, PSTR(STR_HOTEND_OFFSETS));
   LOOP_S_L_N(e, 1, HOTENDS) {
     report_echo_start(forReplay);
-    SERIAL_ECHOPAIR_P(
+    SERIAL_ECHOPGM_P(
       PSTR("  M218 T"), e,
       SP_X_STR, LINEAR_UNIT(hotend_offset[e].x),
       SP_Y_STR, LINEAR_UNIT(hotend_offset[e].y)

Marlin/src/gcode/config/M220.cpp

   if (parser.seenval('S')) feedrate_percentage = parser.value_int();
 
   if (!parser.seen_any()) {
-    SERIAL_ECHOPAIR("FR:", feedrate_percentage);
+    SERIAL_ECHOPGM("FR:", feedrate_percentage);
     SERIAL_CHAR('%');
     SERIAL_EOL();
   }

Marlin/src/gcode/config/M221.cpp

   else {
     SERIAL_ECHO_START();
     SERIAL_CHAR('E', '0' + target_extruder);
-    SERIAL_ECHOPAIR(" Flow: ", planner.flow_percentage[target_extruder]);
+    SERIAL_ECHOPGM(" Flow: ", planner.flow_percentage[target_extruder]);
     SERIAL_CHAR('%');
     SERIAL_EOL();
   }

Marlin/src/gcode/config/M281.cpp

         case Z_PROBE_SERVO_NR:
       #endif
           report_echo_start(forReplay);
-          SERIAL_ECHOLNPAIR("  M281 P", i, " L", servo_angles[i][0], " U", servo_angles[i][1]);
+          SERIAL_ECHOLNPGM("  M281 P", i, " L", servo_angles[i][0], " U", servo_angles[i][1]);
     }
   }
 }

Marlin/src/gcode/config/M301.cpp

   HOTEND_LOOP() {
     if (e == eindex || eindex == -1) {
       report_echo_start(forReplay);
-      SERIAL_ECHOPAIR_P(
+      SERIAL_ECHOPGM_P(
         #if ENABLED(PID_PARAMS_PER_HOTEND)
           PSTR("  M301 E"), e, SP_P_STR
         #else
         , PSTR(" D"), unscalePID_d(PID_PARAM(Kd, e))
       );
       #if ENABLED(PID_EXTRUSION_SCALING)
-        SERIAL_ECHOPAIR_P(SP_C_STR, PID_PARAM(Kc, e));
-        if (e == 0) SERIAL_ECHOPAIR(" L", thermalManager.lpq_len);
+        SERIAL_ECHOPGM_P(SP_C_STR, PID_PARAM(Kc, e));
+        if (e == 0) SERIAL_ECHOPGM(" L", thermalManager.lpq_len);
       #endif
       #if ENABLED(PID_FAN_SCALING)
-        SERIAL_ECHOPAIR(" F", PID_PARAM(Kf, e));
+        SERIAL_ECHOPGM(" F", PID_PARAM(Kf, e));
       #endif
       SERIAL_EOL();
     }

Marlin/src/gcode/config/M302.cpp

     SERIAL_ECHO_START();
     SERIAL_ECHOPGM("Cold extrudes are ");
     SERIAL_ECHOPGM_P(thermalManager.allow_cold_extrude ? PSTR("en") : PSTR("dis"));
-    SERIAL_ECHOLNPAIR("abled (min temp ", thermalManager.extrude_min_temp, "C)");
+    SERIAL_ECHOLNPGM("abled (min temp ", thermalManager.extrude_min_temp, "C)");
   }
 }
 

Marlin/src/gcode/config/M309.cpp

 
 void GcodeSuite::M309_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_CHAMBER_PID));
-  SERIAL_ECHOLNPAIR(
+  SERIAL_ECHOLNPGM(
       "  M309 P", thermalManager.temp_chamber.pid.Kp
     , " I", unscalePID_i(thermalManager.temp_chamber.pid.Ki)
     , " D", unscalePID_d(thermalManager.temp_chamber.pid.Kd)

Marlin/src/gcode/config/M43.cpp

 
     const uint8_t probe_index = parser.byteval('P', Z_PROBE_SERVO_NR);
 
-    SERIAL_ECHOLNPAIR("Servo probe test\n"
+    SERIAL_ECHOLNPGM("Servo probe test\n"
                       ". using index:  ", probe_index,
                       ", deploy angle: ", servo_angles[probe_index][0],
                       ", stow angle:   ", servo_angles[probe_index][1]
       #define PROBE_TEST_PIN Z_MIN_PIN
       constexpr bool probe_inverting = Z_MIN_ENDSTOP_INVERTING;
 
-      SERIAL_ECHOLNPAIR(". Probe Z_MIN_PIN: ", PROBE_TEST_PIN);
+      SERIAL_ECHOLNPGM(". Probe Z_MIN_PIN: ", PROBE_TEST_PIN);
       SERIAL_ECHOPGM(". Z_MIN_ENDSTOP_INVERTING: ");
 
     #else
       #define PROBE_TEST_PIN Z_MIN_PROBE_PIN
       constexpr bool probe_inverting = Z_MIN_PROBE_ENDSTOP_INVERTING;
 
-      SERIAL_ECHOLNPAIR(". Probe Z_MIN_PROBE_PIN: ", PROBE_TEST_PIN);
+      SERIAL_ECHOLNPGM(". Probe Z_MIN_PROBE_PIN: ", PROBE_TEST_PIN);
       SERIAL_ECHOPGM(   ". Z_MIN_PROBE_ENDSTOP_INVERTING: ");
 
     #endif
       if (deploy_state != stow_state) {
         SERIAL_ECHOLNPGM("= Mechanical Switch detected");
         if (deploy_state) {
-          SERIAL_ECHOLNPAIR("  DEPLOYED state: HIGH (logic 1)",
+          SERIAL_ECHOLNPGM("  DEPLOYED state: HIGH (logic 1)",
                             "  STOWED (triggered) state: LOW (logic 0)");
         }
         else {
-          SERIAL_ECHOLNPAIR("  DEPLOYED state: LOW (logic 0)",
+          SERIAL_ECHOLNPGM("  DEPLOYED state: LOW (logic 0)",
                             "  STOWED (triggered) state: HIGH (logic 1)");
         }
         #if ENABLED(BLTOUCH)
         if (probe_counter == 15)
           SERIAL_ECHOLNPGM(": 30ms or more");
         else
-          SERIAL_ECHOLNPAIR(" (+/- 4ms): ", probe_counter * 2);
+          SERIAL_ECHOLNPGM(" (+/- 4ms): ", probe_counter * 2);
 
         if (probe_counter >= 4) {
           if (probe_counter == 15) {

Marlin/src/gcode/config/M92.cpp

                      micro_steps = argH ?: Z_MICROSTEPS;
       const float z_full_step_mm = micro_steps * planner.steps_to_mm[Z_AXIS];
       SERIAL_ECHO_START();
-      SERIAL_ECHOPAIR("{ micro_steps:", micro_steps, ", z_full_step_mm:", z_full_step_mm);
+      SERIAL_ECHOPGM("{ micro_steps:", micro_steps, ", z_full_step_mm:", z_full_step_mm);
       if (wanted) {
         const float best = uint16_t(wanted / z_full_step_mm) * z_full_step_mm;
-        SERIAL_ECHOPAIR(", best:[", best);
+        SERIAL_ECHOPGM(", best:[", best);
         if (best != wanted) { SERIAL_CHAR(','); SERIAL_DECIMAL(best + z_full_step_mm); }
         SERIAL_CHAR(']');
       }
 
 void GcodeSuite::M92_report(const bool forReplay/*=true*/, const int8_t e/*=-1*/) {
   report_heading_etc(forReplay, PSTR(STR_STEPS_PER_UNIT));
-  SERIAL_ECHOPAIR_P(LIST_N(DOUBLE(LINEAR_AXES),
+  SERIAL_ECHOPGM_P(LIST_N(DOUBLE(LINEAR_AXES),
     PSTR("  M92 X"), LINEAR_UNIT(planner.settings.axis_steps_per_mm[X_AXIS]),
     SP_Y_STR, LINEAR_UNIT(planner.settings.axis_steps_per_mm[Y_AXIS]),
     SP_Z_STR, LINEAR_UNIT(planner.settings.axis_steps_per_mm[Z_AXIS]),
     SP_K_STR, LINEAR_UNIT(planner.settings.axis_steps_per_mm[K_AXIS]))
   );
   #if HAS_EXTRUDERS && DISABLED(DISTINCT_E_FACTORS)
-    SERIAL_ECHOPAIR_P(SP_E_STR, VOLUMETRIC_UNIT(planner.settings.axis_steps_per_mm[E_AXIS]));
+    SERIAL_ECHOPGM_P(SP_E_STR, VOLUMETRIC_UNIT(planner.settings.axis_steps_per_mm[E_AXIS]));
   #endif
   SERIAL_EOL();
 
     LOOP_L_N(i, E_STEPPERS) {
       if (e >= 0 && i != e) continue;
       report_echo_start(forReplay);
-      SERIAL_ECHOLNPAIR_P(
+      SERIAL_ECHOLNPGM_P(
         PSTR("  M92 T"), i,
         SP_E_STR, VOLUMETRIC_UNIT(planner.settings.axis_steps_per_mm[E_AXIS_N(i)])
       );

Marlin/src/gcode/control/M111.cpp

     SERIAL_ECHOPGM(STR_DEBUG_OFF);
     #if !defined(__AVR__) || !defined(USBCON)
       #if ENABLED(SERIAL_STATS_RX_BUFFER_OVERRUNS)
-        SERIAL_ECHOPAIR("\nBuffer Overruns: ", MYSERIAL1.buffer_overruns());
+        SERIAL_ECHOPGM("\nBuffer Overruns: ", MYSERIAL1.buffer_overruns());
       #endif
 
       #if ENABLED(SERIAL_STATS_RX_FRAMING_ERRORS)
-        SERIAL_ECHOPAIR("\nFraming Errors: ", MYSERIAL1.framing_errors());
+        SERIAL_ECHOPGM("\nFraming Errors: ", MYSERIAL1.framing_errors());
       #endif
 
       #if ENABLED(SERIAL_STATS_DROPPED_RX)
-        SERIAL_ECHOPAIR("\nDropped bytes: ", MYSERIAL1.dropped());
+        SERIAL_ECHOPGM("\nDropped bytes: ", MYSERIAL1.dropped());
       #endif
 
       #if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
-        SERIAL_ECHOPAIR("\nMax RX Queue Size: ", MYSERIAL1.rxMaxEnqueued());
+        SERIAL_ECHOPGM("\nMax RX Queue Size: ", MYSERIAL1.rxMaxEnqueued());
       #endif
     #endif // !__AVR__ || !USBCON
   }

Marlin/src/gcode/control/M211.cpp

 
 void GcodeSuite::M211_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_SOFT_ENDSTOPS));
-  SERIAL_ECHOPAIR("  M211 S", AS_DIGIT(soft_endstop._enabled), " ; ");
+  SERIAL_ECHOPGM("  M211 S", AS_DIGIT(soft_endstop._enabled), " ; ");
   serialprintln_onoff(soft_endstop._enabled);
 
   report_echo_start(forReplay);

Marlin/src/gcode/control/M605.cpp

           case DXC_DUPLICATION_MODE:  DEBUG_ECHOPGM("DUPLICATION");  break;
           case DXC_MIRRORED_MODE:     DEBUG_ECHOPGM("MIRRORED");     break;
         }
-        DEBUG_ECHOPAIR("\nActive Ext: ", active_extruder);
+        DEBUG_ECHOPGM("\nActive Ext: ", active_extruder);
         if (!active_extruder_parked) DEBUG_ECHOPGM(" NOT ");
         DEBUG_ECHOPGM(" parked.");
-        DEBUG_ECHOPAIR("\nactive_extruder_x_pos: ", current_position.x);
-        DEBUG_ECHOPAIR("\ninactive_extruder_x: ", inactive_extruder_x);
-        DEBUG_ECHOPAIR("\nextruder_duplication_enabled: ", extruder_duplication_enabled);
-        DEBUG_ECHOPAIR("\nduplicate_extruder_x_offset: ", duplicate_extruder_x_offset);
-        DEBUG_ECHOPAIR("\nduplicate_extruder_temp_offset: ", duplicate_extruder_temp_offset);
-        DEBUG_ECHOPAIR("\ndelayed_move_time: ", delayed_move_time);
-        DEBUG_ECHOPAIR("\nX1 Home X: ", x_home_pos(0), "\nX1_MIN_POS=", X1_MIN_POS, "\nX1_MAX_POS=", X1_MAX_POS);
-        DEBUG_ECHOPAIR("\nX2 Home X: ", x_home_pos(1), "\nX2_MIN_POS=", X2_MIN_POS, "\nX2_MAX_POS=", X2_MAX_POS);
-        DEBUG_ECHOPAIR("\nX2_HOME_DIR=", X2_HOME_DIR, "\nX2_HOME_POS=", X2_HOME_POS);
-        DEBUG_ECHOPAIR("\nDEFAULT_DUAL_X_CARRIAGE_MODE=", STRINGIFY(DEFAULT_DUAL_X_CARRIAGE_MODE));
-        DEBUG_ECHOPAIR("\toolchange_settings.z_raise=", toolchange_settings.z_raise);
-        DEBUG_ECHOPAIR("\nDEFAULT_DUPLICATION_X_OFFSET=", DEFAULT_DUPLICATION_X_OFFSET);
+        DEBUG_ECHOPGM("\nactive_extruder_x_pos: ", current_position.x);
+        DEBUG_ECHOPGM("\ninactive_extruder_x: ", inactive_extruder_x);
+        DEBUG_ECHOPGM("\nextruder_duplication_enabled: ", extruder_duplication_enabled);
+        DEBUG_ECHOPGM("\nduplicate_extruder_x_offset: ", duplicate_extruder_x_offset);
+        DEBUG_ECHOPGM("\nduplicate_extruder_temp_offset: ", duplicate_extruder_temp_offset);
+        DEBUG_ECHOPGM("\ndelayed_move_time: ", delayed_move_time);
+        DEBUG_ECHOPGM("\nX1 Home X: ", x_home_pos(0), "\nX1_MIN_POS=", X1_MIN_POS, "\nX1_MAX_POS=", X1_MAX_POS);
+        DEBUG_ECHOPGM("\nX2 Home X: ", x_home_pos(1), "\nX2_MIN_POS=", X2_MIN_POS, "\nX2_MAX_POS=", X2_MAX_POS);
+        DEBUG_ECHOPGM("\nX2_HOME_DIR=", X2_HOME_DIR, "\nX2_HOME_POS=", X2_HOME_POS);
+        DEBUG_ECHOPGM("\nDEFAULT_DUAL_X_CARRIAGE_MODE=", STRINGIFY(DEFAULT_DUAL_X_CARRIAGE_MODE));
+        DEBUG_ECHOPGM("\toolchange_settings.z_raise=", toolchange_settings.z_raise);
+        DEBUG_ECHOPGM("\nDEFAULT_DUPLICATION_X_OFFSET=", DEFAULT_DUPLICATION_X_OFFSET);
         DEBUG_EOL();
 
         HOTEND_LOOP() {
-          DEBUG_ECHOPAIR_P(SP_T_STR, e);
-          LOOP_LINEAR_AXES(a) DEBUG_ECHOPAIR("  hotend_offset[", e, "].", AS_CHAR(AXIS_CHAR(a) | 0x20), "=", hotend_offset[e][a]);
+          DEBUG_ECHOPGM_P(SP_T_STR, e);
+          LOOP_LINEAR_AXES(a) DEBUG_ECHOPGM("  hotend_offset[", e, "].", AS_CHAR(AXIS_CHAR(a) | 0x20), "=", hotend_offset[e][a]);
           DEBUG_EOL();
         }
         DEBUG_EOL();

Marlin/src/gcode/control/M993_M994.cpp

   char fname[] = "spiflash.bin";
   card.openFileWrite(fname);
   if (!card.isFileOpen()) {
-    SERIAL_ECHOLNPAIR("Failed to open ", fname, " to write.");
+    SERIAL_ECHOLNPGM("Failed to open ", fname, " to write.");
     return;
   }
 
   char fname[] = "spiflash.bin";
   card.openFileRead(fname);
   if (!card.isFileOpen()) {
-    SERIAL_ECHOLNPAIR("Failed to open ", fname, " to read.");
+    SERIAL_ECHOLNPGM("Failed to open ", fname, " to read.");
     return;
   }
 

Marlin/src/gcode/control/T.cpp

 void GcodeSuite::T(const int8_t tool_index) {
 
   DEBUG_SECTION(log_T, "T", DEBUGGING(LEVELING));
-  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPAIR("...(", tool_index, ")");
+  if (DEBUGGING(LEVELING)) DEBUG_ECHOLNPGM("...(", tool_index, ")");
 
   // Count this command as movement / activity
   reset_stepper_timeout();

Marlin/src/gcode/eeprom/M500-M504.cpp

         if (dowrite) {
           val = parser.byteval('V');
           persistentStore.write_data(addr, &val);
-          SERIAL_ECHOLNPAIR("Wrote address ", addr, " with ", val);
+          SERIAL_ECHOLNPGM("Wrote address ", addr, " with ", val);
         }
         else {
           if (parser.seenval('T')) {
             const int endaddr = parser.value_ushort();
             while (addr <= endaddr) {
               persistentStore.read_data(addr, &val);
-              SERIAL_ECHOLNPAIR("0x", hex_word(addr), ":", hex_byte(val));
+              SERIAL_ECHOLNPGM("0x", hex_word(addr), ":", hex_byte(val));
               addr++;
               safe_delay(10);
             }
           }
           else {
             persistentStore.read_data(addr, &val);
-            SERIAL_ECHOLNPAIR("Read address ", addr, " and got ", val);
+            SERIAL_ECHOLNPGM("Read address ", addr, " and got ", val);
           }
         }
         return;

Marlin/src/gcode/feature/L6470/M122.cpp

     if (!(sh.STATUS_AXIS & sh.STATUS_AXIS_WRONG_CMD)) SERIAL_ECHOPGM("IN");
     SERIAL_ECHOPGM("VALID    ");
     SERIAL_ECHOPGM_P(sh.STATUS_AXIS & sh.STATUS_AXIS_NOTPERF_CMD ?  PSTR("COMPLETED    ") : PSTR("Not PERFORMED"));
-    SERIAL_ECHOPAIR("\n...THERMAL: ", !(sh.STATUS_AXIS & sh.STATUS_AXIS_TH_SD) ? "SHUTDOWN       " : !(sh.STATUS_AXIS & sh.STATUS_AXIS_TH_WRN) ? "WARNING        " : "OK             ");
+    SERIAL_ECHOPGM("\n...THERMAL: ", !(sh.STATUS_AXIS & sh.STATUS_AXIS_TH_SD) ? "SHUTDOWN       " : !(sh.STATUS_AXIS & sh.STATUS_AXIS_TH_WRN) ? "WARNING        " : "OK             ");
   }
   SERIAL_ECHOPGM("   OVERCURRENT:"); echo_yes_no((sh.STATUS_AXIS & sh.STATUS_AXIS_OCD) == 0);
   if (sh.STATUS_AXIS_LAYOUT != L6474_STATUS_LAYOUT) {

Marlin/src/gcode/feature/L6470/M906.cpp

     #if ENABLED(L6470_CHITCHAT)
       char tmp[10];
       sprintf_P(tmp, PSTR("%4x   "), status);
-      DEBUG_ECHOPAIR("   status: ", tmp);
+      DEBUG_ECHOPGM("   status: ", tmp);
       print_bin(status);
     #else
       UNUSED(status);
       }
       SERIAL_EOL();
 
-      SERIAL_ECHOPAIR("...MicroSteps: ", MicroSteps,
+      SERIAL_ECHOPGM("...MicroSteps: ", MicroSteps,
                       "   ADC_OUT: ", L6470_ADC_out);
       SERIAL_ECHOPGM("   Vs_compensation: ");
       SERIAL_ECHOPGM_P((motor.GetParam(sh.L6470_AXIS_CONFIG) & CONFIG_EN_VSCOMP) ? PSTR("ENABLED ") : PSTR("DISABLED"));
-      SERIAL_ECHOLNPAIR("   Compensation coefficient: ~", comp_coef * 0.01f);
+      SERIAL_ECHOLNPGM("   Compensation coefficient: ~", comp_coef * 0.01f);
 
-      SERIAL_ECHOPAIR("...KVAL_HOLD: ", motor.GetParam(L6470_KVAL_HOLD),
+      SERIAL_ECHOPGM("...KVAL_HOLD: ", motor.GetParam(L6470_KVAL_HOLD),
                       "   KVAL_RUN : ", motor.GetParam(L6470_KVAL_RUN),
                       "   KVAL_ACC: ", motor.GetParam(L6470_KVAL_ACC),
                       "   KVAL_DEC: ", motor.GetParam(L6470_KVAL_DEC),
       SERIAL_ECHOLNPGM(" mA)   Motor Status: NA");
 
       const uint16_t MicroSteps = _BV(motor.GetParam(L6470_STEP_MODE) & 0x07); //NOMORE(MicroSteps, 16);
-      SERIAL_ECHOPAIR("...MicroSteps: ", MicroSteps,
+      SERIAL_ECHOPGM("...MicroSteps: ", MicroSteps,
                       "   ADC_OUT: ", L6470_ADC_out);
 
       SERIAL_ECHOLNPGM("   Vs_compensation: NA\n");
           case 1:  DEBUG_ECHOLNPGM("75V/uS")  ; break;
           case 2:  DEBUG_ECHOLNPGM("110V/uS") ; break;
           case 3:  DEBUG_ECHOLNPGM("260V/uS") ; break;
-          default: DEBUG_ECHOLNPAIR("slew rate: ", (motor.GetParam(sh.L6470_AXIS_CONFIG) & CONFIG_POW_SR) >> CONFIG_POW_SR_BIT); break;
+          default: DEBUG_ECHOLNPGM("slew rate: ", (motor.GetParam(sh.L6470_AXIS_CONFIG) & CONFIG_POW_SR) >> CONFIG_POW_SR_BIT); break;
         }
       #endif
       SERIAL_EOL();

Marlin/src/gcode/feature/L6470/M916-918.cpp

   if (L64xxManager.get_user_input(driver_count, axis_index, axis_mon, position_max, position_min, final_feedrate, kval_hold, over_current_flag, OCD_TH_val, STALL_TH_val, over_current_threshold))
     return;  // quit if invalid user input
 
-  DEBUG_ECHOLNPAIR("feedrate = ", final_feedrate);
+  DEBUG_ECHOLNPGM("feedrate = ", final_feedrate);
 
   planner.synchronize();                             // wait for all current movement commands to complete
 
   do {
 
     if (sh.STATUS_AXIS_LAYOUT == L6474_STATUS_LAYOUT)
-      DEBUG_ECHOLNPAIR("TVAL current (mA) = ", (M91x_counter + 1) * sh.AXIS_STALL_CURRENT_CONSTANT_INV);        // report TVAL current for this run
+      DEBUG_ECHOLNPGM("TVAL current (mA) = ", (M91x_counter + 1) * sh.AXIS_STALL_CURRENT_CONSTANT_INV);        // report TVAL current for this run
     else
-      DEBUG_ECHOLNPAIR("kval_hold = ", M91x_counter);                                   // report KVAL_HOLD for this run
+      DEBUG_ECHOLNPGM("kval_hold = ", M91x_counter);                                   // report KVAL_HOLD for this run
 
     for (j = 0; j < driver_count; j++)
       L64xxManager.set_param(axis_index[j], L6470_KVAL_HOLD, M91x_counter);  //set KVAL_HOLD or TVAL (same register address)
   if (L64xxManager.get_user_input(driver_count, axis_index, axis_mon, position_max, position_min, final_feedrate, kval_hold, over_current_flag, OCD_TH_val, STALL_TH_val, over_current_threshold))
     return;  // quit if invalid user input
 
-  DEBUG_ECHOLNPAIR("feedrate = ", final_feedrate);
+  DEBUG_ECHOLNPGM("feedrate = ", final_feedrate);
 
   planner.synchronize();                             // wait for all current movement commands to complete
 
                                           // 2 - OCD finalized - decreasing STALL - exit when STALL warning happens
                                           // 3 - OCD finalized - increasing STALL - exit when STALL warning stop
                                           // 4 - all testing completed
-  DEBUG_ECHOPAIR(".\n.\n.\nover_current threshold : ", (OCD_TH_val + 1) * 375);   // first status display
-  DEBUG_ECHOPAIR("  (OCD_TH:  : ", OCD_TH_val);
+  DEBUG_ECHOPGM(".\n.\n.\nover_current threshold : ", (OCD_TH_val + 1) * 375);   // first status display
+  DEBUG_ECHOPGM("  (OCD_TH:  : ", OCD_TH_val);
   if (sh.STATUS_AXIS_LAYOUT != L6474_STATUS_LAYOUT) {
-    DEBUG_ECHOPAIR(")   Stall threshold: ", (STALL_TH_val + 1) * 31.25);
-    DEBUG_ECHOPAIR("  (STALL_TH: ", STALL_TH_val);
+    DEBUG_ECHOPGM(")   Stall threshold: ", (STALL_TH_val + 1) * 31.25);
+    DEBUG_ECHOPGM("  (STALL_TH: ", STALL_TH_val);
   }
   DEBUG_ECHOLNPGM(")");
 
   do {
 
-    if (sh.STATUS_AXIS_LAYOUT != L6474_STATUS_LAYOUT) DEBUG_ECHOPAIR("STALL threshold : ", (STALL_TH_val + 1) * 31.25);
-    DEBUG_ECHOLNPAIR("   OCD threshold : ", (OCD_TH_val + 1) * 375);
+    if (sh.STATUS_AXIS_LAYOUT != L6474_STATUS_LAYOUT) DEBUG_ECHOPGM("STALL threshold : ", (STALL_TH_val + 1) * 31.25);
+    DEBUG_ECHOLNPGM("   OCD threshold : ", (OCD_TH_val + 1) * 375);
 
     sprintf_P(gcode_string, PSTR("G0 %s%03d F%03d"), temp_axis_string, uint16_t(position_min), uint16_t(final_feedrate));
     gcode.process_subcommands_now_P(gcode_string);
         if (!(k % 4)) {
           kval_hold *= 0.95;
           DEBUG_EOL();
-          DEBUG_ECHOLNPAIR("Lowering KVAL_HOLD by about 5% to ", kval_hold);
+          DEBUG_ECHOLNPGM("Lowering KVAL_HOLD by about 5% to ", kval_hold);
           for (j = 0; j < driver_count; j++)
             L64xxManager.set_param(axis_index[j], L6470_KVAL_HOLD, kval_hold);
         }
   }
   m_steps = L64xxManager.get_param(axis_index[0], L6470_STEP_MODE) & 0x07;   // get microsteps
 
-  DEBUG_ECHOLNPAIR("Microsteps = ", _BV(m_steps));
-  DEBUG_ECHOLNPAIR("target (maximum) feedrate = ", final_feedrate);
+  DEBUG_ECHOLNPGM("Microsteps = ", _BV(m_steps));
+  DEBUG_ECHOLNPGM("target (maximum) feedrate = ", final_feedrate);
 
   const float feedrate_inc = final_feedrate / 10,   // Start at 1/10 of max & go up by 1/10 per step
               fr_limit = final_feedrate * 0.99f;    // Rounding-safe comparison value
 
   do {
     current_feedrate += feedrate_inc;
-    DEBUG_ECHOLNPAIR("...feedrate = ", current_feedrate);
+    DEBUG_ECHOLNPGM("...feedrate = ", current_feedrate);
 
     sprintf_P(gcode_string, PSTR("G0 %s%03d F%03d"), temp_axis_string, uint16_t(position_min), uint16_t(current_feedrate));
     gcode.process_subcommands_now_P(gcode_string);

Marlin/src/gcode/feature/advance/M900.cpp

     #if ENABLED(EXTRA_LIN_ADVANCE_K)
 
       #if EXTRUDERS < 2
-        SERIAL_ECHOLNPAIR("Advance S", new_slot, " K", kref, "(S", !new_slot, " K", lref, ")");
+        SERIAL_ECHOLNPGM("Advance S", new_slot, " K", kref, "(S", !new_slot, " K", lref, ")");
       #else
         LOOP_L_N(i, EXTRUDERS) {
           const bool slot = TEST(lin_adv_slot, i);
-          SERIAL_ECHOLNPAIR("Advance T", i, " S", slot, " K", planner.extruder_advance_K[i],
+          SERIAL_ECHOLNPGM("Advance T", i, " S", slot, " K", planner.extruder_advance_K[i],
                             "(S", !slot, " K", other_extruder_advance_K[i], ")");
           SERIAL_EOL();
         }
 
       SERIAL_ECHO_START();
       #if EXTRUDERS < 2
-        SERIAL_ECHOLNPAIR("Advance K=", planner.extruder_advance_K[0]);
+        SERIAL_ECHOLNPGM("Advance K=", planner.extruder_advance_K[0]);
       #else
         SERIAL_ECHOPGM("Advance K");
         LOOP_L_N(i, EXTRUDERS) {
   report_heading(forReplay, PSTR(STR_LINEAR_ADVANCE));
   #if EXTRUDERS < 2
     report_echo_start(forReplay);
-    SERIAL_ECHOLNPAIR("  M900 K", planner.extruder_advance_K[0]);
+    SERIAL_ECHOLNPGM("  M900 K", planner.extruder_advance_K[0]);
   #else
     LOOP_L_N(i, EXTRUDERS) {
       report_echo_start(forReplay);
-      SERIAL_ECHOLNPAIR("  M900 T", i, " K", planner.extruder_advance_K[i]);
+      SERIAL_ECHOLNPGM("  M900 T", i, " K", planner.extruder_advance_K[i]);
     }
   #endif
 }

Marlin/src/gcode/feature/controllerfan/M710.cpp

 
 void GcodeSuite::M710_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_CONTROLLER_FAN));
-  SERIAL_ECHOLNPAIR("  M710"
+  SERIAL_ECHOLNPGM("  M710"
     " S", int(controllerFan.settings.active_speed),
     " I", int(controllerFan.settings.idle_speed),
     " A", int(controllerFan.settings.auto_mode),

Marlin/src/gcode/feature/digipot/M907-M910.cpp

   void GcodeSuite::M907_report(const bool forReplay/*=true*/) {
     report_heading_etc(forReplay, PSTR(STR_STEPPER_MOTOR_CURRENTS));
     #if HAS_MOTOR_CURRENT_PWM
-      SERIAL_ECHOLNPAIR_P(                                    // PWM-based has 3 values:
+      SERIAL_ECHOLNPGM_P(                                    // PWM-based has 3 values:
           PSTR("  M907 X"), stepper.motor_current_setting[0]  // X and Y
         , SP_Z_STR,         stepper.motor_current_setting[1]  // Z
         , SP_E_STR,         stepper.motor_current_setting[2]  // E

Marlin/src/gcode/feature/filwidth/M404-M407.cpp

     planner.volumetric_area_nominal = CIRCLE_AREA(filwidth.nominal_mm * 0.5);
   }
   else
-    SERIAL_ECHOLNPAIR("Filament dia (nominal mm):", filwidth.nominal_mm);
+    SERIAL_ECHOLNPGM("Filament dia (nominal mm):", filwidth.nominal_mm);
 }
 
 /**
  * M407: Get measured filament diameter on serial output
  */
 void GcodeSuite::M407() {
-  SERIAL_ECHOLNPAIR("Filament dia (measured mm):", filwidth.measured_mm);
+  SERIAL_ECHOLNPGM("Filament dia (measured mm):", filwidth.measured_mm);
 }
 
 #endif // FILAMENT_WIDTH_SENSOR

Marlin/src/gcode/feature/mixing/M166.cpp

 #include "../../../feature/mixing.h"
 
 inline void echo_mix() {
-  SERIAL_ECHOPAIR(" (", mixer.mix[0], "%|", mixer.mix[1], "%)");
+  SERIAL_ECHOPGM(" (", mixer.mix[0], "%|", mixer.mix[1], "%)");
 }
 
 inline void echo_zt(const int t, const_float_t z) {
   mixer.update_mix_from_vtool(t);
-  SERIAL_ECHOPAIR_P(SP_Z_STR, z, SP_T_STR, t);
+  SERIAL_ECHOPGM_P(SP_Z_STR, z, SP_T_STR, t);
   echo_mix();
 }
 
 
     #if ENABLED(GRADIENT_VTOOL)
       if (mixer.gradient.vtool_index >= 0) {
-        SERIAL_ECHOPAIR(" (T", mixer.gradient.vtool_index);
+        SERIAL_ECHOPGM(" (T", mixer.gradient.vtool_index);
         SERIAL_CHAR(')');
       }
     #endif

Marlin/src/gcode/feature/password/M510-M512.cpp

       if (password.value_entry < CAT(1e, PASSWORD_LENGTH)) {
         password.is_set = true;
         password.value = password.value_entry;
-        SERIAL_ECHOLNPAIR(STR_PASSWORD_SET, password.value); // TODO: Update password.string
+        SERIAL_ECHOLNPGM(STR_PASSWORD_SET, password.value); // TODO: Update password.string
       }
       else
         SERIAL_ECHOLNPGM(STR_PASSWORD_TOO_LONG);

Marlin/src/gcode/feature/pause/G60.cpp

   SBI(saved_slots[slot >> 3], slot & 0x07);
 
   #if ENABLED(SAVED_POSITIONS_DEBUG)
-    DEBUG_ECHOPAIR(STR_SAVED_POS " S", slot);
+    DEBUG_ECHOPGM(STR_SAVED_POS " S", slot);
     const xyze_pos_t &pos = stored_position[slot];
     DEBUG_ECHOLNPAIR_F_P(
       LIST_N(DOUBLE(LOGICAL_AXES), SP_E_STR, pos.e,

Marlin/src/gcode/feature/pause/G61.cpp

   }
   else {
     if (parser.seen(LINEAR_AXIS_GANG("X", "Y", "Z", AXIS4_STR, AXIS5_STR, AXIS6_STR))) {
-      DEBUG_ECHOPAIR(STR_RESTORING_POS " S", slot);
+      DEBUG_ECHOPGM(STR_RESTORING_POS " S", slot);
       LOOP_LINEAR_AXES(i) {
         destination[i] = parser.seen(AXIS_CHAR(i))
           ? stored_position[slot][i] + parser.value_axis_units((AxisEnum)i)
     }
     #if HAS_EXTRUDERS
       if (parser.seen_test('E')) {
-        DEBUG_ECHOLNPAIR(STR_RESTORING_POS " S", slot, " E", current_position.e, "=>", stored_position[slot].e);
+        DEBUG_ECHOLNPGM(STR_RESTORING_POS " S", slot, " E", current_position.e, "=>", stored_position[slot].e);
         SYNC_E(stored_position[slot].e);
       }
     #endif

Marlin/src/gcode/feature/pause/M603.cpp

 
   #if EXTRUDERS == 1
     report_echo_start(forReplay);
-    SERIAL_ECHOPAIR("  M603 L", LINEAR_UNIT(fc_settings[0].load_length), " U", LINEAR_UNIT(fc_settings[0].unload_length), " ;");
+    SERIAL_ECHOPGM("  M603 L", LINEAR_UNIT(fc_settings[0].load_length), " U", LINEAR_UNIT(fc_settings[0].unload_length), " ;");
     say_units();
   #else
     LOOP_L_N(e, EXTRUDERS) {
       report_echo_start(forReplay);
-      SERIAL_ECHOPAIR("  M603 T", e, " L", LINEAR_UNIT(fc_settings[e].load_length), " U", LINEAR_UNIT(fc_settings[e].unload_length), " ;");
+      SERIAL_ECHOPGM("  M603 T", e, " L", LINEAR_UNIT(fc_settings[e].load_length), " U", LINEAR_UNIT(fc_settings[e].unload_length), " ;");
       say_units();
     }
   #endif

Marlin/src/gcode/feature/power_monitor/M430.cpp

     #endif
   #endif
   if (do_report) {
-    SERIAL_ECHOLNPAIR(
+    SERIAL_ECHOLNPGM(
       #if ENABLED(POWER_MONITOR_CURRENT)
         "Current: ", power_monitor.getAmps(), "A"
         #if ENABLED(POWER_MONITOR_VOLTAGE)

Marlin/src/gcode/feature/powerloss/M413.cpp

 
 void GcodeSuite::M413_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_POWER_LOSS_RECOVERY));
-  SERIAL_ECHOPAIR("  M413 S", AS_DIGIT(recovery.enabled), " ; ");
+  SERIAL_ECHOPGM("  M413 S", AS_DIGIT(recovery.enabled), " ; ");
   serialprintln_onoff(recovery.enabled);
 }
 

Marlin/src/gcode/feature/runout/M412.cpp

     SERIAL_ECHOPGM("Filament runout ");
     serialprint_onoff(runout.enabled);
     #if HAS_FILAMENT_RUNOUT_DISTANCE
-      SERIAL_ECHOPAIR(" ; Distance ", runout.runout_distance(), "mm");
+      SERIAL_ECHOPGM(" ; Distance ", runout.runout_distance(), "mm");
     #endif
     #if ENABLED(HOST_ACTION_COMMANDS)
       SERIAL_ECHOPGM(" ; Host handling ");
 
 void GcodeSuite::M412_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_FILAMENT_RUNOUT_SENSOR));
-  SERIAL_ECHOLNPAIR(
+  SERIAL_ECHOLNPGM(
     "  M412 S", runout.enabled
     #if HAS_FILAMENT_RUNOUT_DISTANCE
       , " D", LINEAR_UNIT(runout.runout_distance())

Marlin/src/gcode/feature/trinamic/M906.cpp

   #if AXIS_IS_TMC(X) || AXIS_IS_TMC(Y) || AXIS_IS_TMC(Z)
     say_M906(forReplay);
     #if AXIS_IS_TMC(X)
-      SERIAL_ECHOPAIR_P(SP_X_STR, stepperX.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_X_STR, stepperX.getMilliamps());
     #endif
     #if AXIS_IS_TMC(Y)
-      SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_Y_STR, stepperY.getMilliamps());
     #endif
     #if AXIS_IS_TMC(Z)
-      SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ.getMilliamps());
     #endif
     SERIAL_EOL();
   #endif
     say_M906(forReplay);
     SERIAL_ECHOPGM(" I1");
     #if AXIS_IS_TMC(X2)
-      SERIAL_ECHOPAIR_P(SP_X_STR, stepperX2.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_X_STR, stepperX2.getMilliamps());
     #endif
     #if AXIS_IS_TMC(Y2)
-      SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY2.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_Y_STR, stepperY2.getMilliamps());
     #endif
     #if AXIS_IS_TMC(Z2)
-      SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ2.getMilliamps());
+      SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ2.getMilliamps());
     #endif
     SERIAL_EOL();
   #endif
 
   #if AXIS_IS_TMC(Z3)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" I2 Z", stepperZ3.getMilliamps());
+    SERIAL_ECHOLNPGM(" I2 Z", stepperZ3.getMilliamps());
   #endif
 
   #if AXIS_IS_TMC(Z4)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" I3 Z", stepperZ4.getMilliamps());
+    SERIAL_ECHOLNPGM(" I3 Z", stepperZ4.getMilliamps());
   #endif
 
   #if AXIS_IS_TMC(I)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR_P(SP_I_STR, stepperI.getMilliamps());
+    SERIAL_ECHOLNPGM_P(SP_I_STR, stepperI.getMilliamps());
   #endif
   #if AXIS_IS_TMC(J)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR_P(SP_J_STR, stepperJ.getMilliamps());
+    SERIAL_ECHOLNPGM_P(SP_J_STR, stepperJ.getMilliamps());
   #endif
   #if AXIS_IS_TMC(K)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR_P(SP_K_STR, stepperK.getMilliamps());
+    SERIAL_ECHOLNPGM_P(SP_K_STR, stepperK.getMilliamps());
   #endif
 
   #if AXIS_IS_TMC(E0)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T0 E", stepperE0.getMilliamps());
+    SERIAL_ECHOLNPGM(" T0 E", stepperE0.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E1)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T1 E", stepperE1.getMilliamps());
+    SERIAL_ECHOLNPGM(" T1 E", stepperE1.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E2)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T2 E", stepperE2.getMilliamps());
+    SERIAL_ECHOLNPGM(" T2 E", stepperE2.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E3)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T3 E", stepperE3.getMilliamps());
+    SERIAL_ECHOLNPGM(" T3 E", stepperE3.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E4)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T4 E", stepperE4.getMilliamps());
+    SERIAL_ECHOLNPGM(" T4 E", stepperE4.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E5)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T5 E", stepperE5.getMilliamps());
+    SERIAL_ECHOLNPGM(" T5 E", stepperE5.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E6)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T6 E", stepperE6.getMilliamps());
+    SERIAL_ECHOLNPGM(" T6 E", stepperE6.getMilliamps());
   #endif
   #if AXIS_IS_TMC(E7)
     say_M906(forReplay);
-    SERIAL_ECHOLNPAIR(" T7 E", stepperE7.getMilliamps());
+    SERIAL_ECHOLNPGM(" T7 E", stepperE7.getMilliamps());
   #endif
   SERIAL_EOL();
 }

Marlin/src/gcode/feature/trinamic/M911-M914.cpp

     #if X_HAS_STEALTHCHOP || Y_HAS_STEALTHCHOP || Z_HAS_STEALTHCHOP
       say_M913(forReplay);
       #if X_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_X_STR, stepperX.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_X_STR, stepperX.get_pwm_thrs());
       #endif
       #if Y_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_Y_STR, stepperY.get_pwm_thrs());
       #endif
       #if Z_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ.get_pwm_thrs());
       #endif
       SERIAL_EOL();
     #endif
       say_M913(forReplay);
       SERIAL_ECHOPGM(" I1");
       #if X2_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_X_STR, stepperX2.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_X_STR, stepperX2.get_pwm_thrs());
       #endif
       #if Y2_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY2.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_Y_STR, stepperY2.get_pwm_thrs());
       #endif
       #if Z2_HAS_STEALTHCHOP
-        SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ2.get_pwm_thrs());
+        SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ2.get_pwm_thrs());
       #endif
       SERIAL_EOL();
     #endif
 
     #if Z3_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" I2 Z", stepperZ3.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" I2 Z", stepperZ3.get_pwm_thrs());
     #endif
 
     #if Z4_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" I3 Z", stepperZ4.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" I3 Z", stepperZ4.get_pwm_thrs());
     #endif
 
     #if I_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_I_STR, stepperI.get_pwm_thrs());
+      SERIAL_ECHOLNPGM_P(SP_I_STR, stepperI.get_pwm_thrs());
     #endif
     #if J_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_J_STR, stepperJ.get_pwm_thrs());
+      SERIAL_ECHOLNPGM_P(SP_J_STR, stepperJ.get_pwm_thrs());
     #endif
     #if K_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_K_STR, stepperK.get_pwm_thrs());
+      SERIAL_ECHOLNPGM_P(SP_K_STR, stepperK.get_pwm_thrs());
     #endif
 
     #if E0_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T0 E", stepperE0.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T0 E", stepperE0.get_pwm_thrs());
     #endif
     #if E1_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T1 E", stepperE1.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T1 E", stepperE1.get_pwm_thrs());
     #endif
     #if E2_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T2 E", stepperE2.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T2 E", stepperE2.get_pwm_thrs());
     #endif
     #if E3_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T3 E", stepperE3.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T3 E", stepperE3.get_pwm_thrs());
     #endif
     #if E4_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T4 E", stepperE4.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T4 E", stepperE4.get_pwm_thrs());
     #endif
     #if E5_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T5 E", stepperE5.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T5 E", stepperE5.get_pwm_thrs());
     #endif
     #if E6_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T6 E", stepperE6.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T6 E", stepperE6.get_pwm_thrs());
     #endif
     #if E7_HAS_STEALTHCHOP
       say_M913(forReplay);
-      SERIAL_ECHOLNPAIR(" T7 E", stepperE7.get_pwm_thrs());
+      SERIAL_ECHOLNPGM(" T7 E", stepperE7.get_pwm_thrs());
     #endif
     SERIAL_EOL();
   }
     #if X_SENSORLESS || Y_SENSORLESS || Z_SENSORLESS
       say_M914(forReplay);
       #if X_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_X_STR, stepperX.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_X_STR, stepperX.homing_threshold());
       #endif
       #if Y_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_Y_STR, stepperY.homing_threshold());
       #endif
       #if Z_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ.homing_threshold());
       #endif
       SERIAL_EOL();
     #endif
       say_M914(forReplay);
       SERIAL_ECHOPGM(" I1");
       #if X2_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_X_STR, stepperX2.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_X_STR, stepperX2.homing_threshold());
       #endif
       #if Y2_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_Y_STR, stepperY2.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_Y_STR, stepperY2.homing_threshold());
       #endif
       #if Z2_SENSORLESS
-        SERIAL_ECHOPAIR_P(SP_Z_STR, stepperZ2.homing_threshold());
+        SERIAL_ECHOPGM_P(SP_Z_STR, stepperZ2.homing_threshold());
       #endif
       SERIAL_EOL();
     #endif
 
     #if Z3_SENSORLESS
       say_M914(forReplay);
-      SERIAL_ECHOLNPAIR(" I2 Z", stepperZ3.homing_threshold());
+      SERIAL_ECHOLNPGM(" I2 Z", stepperZ3.homing_threshold());
     #endif
 
     #if Z4_SENSORLESS
       say_M914(forReplay);
-      SERIAL_ECHOLNPAIR(" I3 Z", stepperZ4.homing_threshold());
+      SERIAL_ECHOLNPGM(" I3 Z", stepperZ4.homing_threshold());
     #endif
 
     #if I_SENSORLESS
       say_M914(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_I_STR, stepperI.homing_threshold());
+      SERIAL_ECHOLNPGM_P(SP_I_STR, stepperI.homing_threshold());
     #endif
     #if J_SENSORLESS
       say_M914(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_J_STR, stepperJ.homing_threshold());
+      SERIAL_ECHOLNPGM_P(SP_J_STR, stepperJ.homing_threshold());
     #endif
     #if K_SENSORLESS
       say_M914(forReplay);
-      SERIAL_ECHOLNPAIR_P(SP_K_STR, stepperK.homing_threshold());
+      SERIAL_ECHOLNPGM_P(SP_K_STR, stepperK.homing_threshold());
     #endif
   }
 

Marlin/src/gcode/gcode.cpp

     if (e < EXTRUDERS) return e;
     SERIAL_ECHO_START();
     SERIAL_CHAR('M'); SERIAL_ECHO(parser.codenum);
-    SERIAL_ECHOLNPAIR(" " STR_INVALID_EXTRUDER " ", e);
+    SERIAL_ECHOLNPGM(" " STR_INVALID_EXTRUDER " ", e);
     return -1;
   }
   return active_extruder;
   if (e == -1)
     SERIAL_ECHOLNPGM(" " STR_E_STEPPER_NOT_SPECIFIED);
   else
-    SERIAL_ECHOLNPAIR(" " STR_INVALID_E_STEPPER " ", e);
+    SERIAL_ECHOLNPGM(" " STR_INVALID_E_STEPPER " ", e);
   return -1;
 }
 
     SERIAL_ECHO_START();
     SERIAL_ECHOLN(command.buffer);
     #if ENABLED(M100_FREE_MEMORY_DUMPER)
-      SERIAL_ECHOPAIR("slot:", queue.ring_buffer.index_r);
+      SERIAL_ECHOPGM("slot:", queue.ring_buffer.index_r);
       M100_dump_routine(PSTR("   Command Queue:"), (const char*)&queue.ring_buffer, sizeof(queue.ring_buffer));
     #endif
   }

Marlin/src/gcode/gcode_d.cpp

       break;
 
     case 7: // D7 dump the current serial port type (hence configuration)
-      SERIAL_ECHOLNPAIR("Current serial configuration RX_BS:", RX_BUFFER_SIZE, ", TX_BS:", TX_BUFFER_SIZE);
+      SERIAL_ECHOLNPGM("Current serial configuration RX_BS:", RX_BUFFER_SIZE, ", TX_BS:", TX_BUFFER_SIZE);
       SERIAL_ECHOLN(gtn(&SERIAL_IMPL));
       break;
 
       case 101: { // D101 Test SD Write
         card.openFileWrite("test.gco");
         if (!card.isFileOpen()) {
-          SERIAL_ECHOLNPAIR("Failed to open test.gco to write.");
+          SERIAL_ECHOLNPGM("Failed to open test.gco to write.");
           return;
         }
         __attribute__((aligned(sizeof(size_t)))) uint8_t buf[512];
         char testfile[] = "test.gco";
         card.openFileRead(testfile);
         if (!card.isFileOpen()) {
-          SERIAL_ECHOLNPAIR("Failed to open test.gco to read.");
+          SERIAL_ECHOLNPGM("Failed to open test.gco to read.");
           return;
         }
         __attribute__((aligned(sizeof(size_t)))) uint8_t buf[512];

Marlin/src/gcode/geometry/G53-G59.cpp

     process_parsed_command(); // ...process the chained command
     select_coordinate_system(old_system);
     #ifdef DEBUG_M53
-      SERIAL_ECHOLNPAIR("Go back to workspace ", old_system);
+      SERIAL_ECHOLNPGM("Go back to workspace ", old_system);
       report_current_position();
     #endif
   }
 void G54_59(uint8_t subcode=0) {
   const int8_t _space = parser.codenum - 54 + subcode;
   if (gcode.select_coordinate_system(_space)) {
-    SERIAL_ECHOLNPAIR("Select workspace ", _space);
+    SERIAL_ECHOLNPGM("Select workspace ", _space);
     report_current_position();
   }
 }

Marlin/src/gcode/geometry/M206_M428.cpp

 
 void GcodeSuite::M206_report(const bool forReplay/*=true*/) {
   report_heading_etc(forReplay, PSTR(STR_HOME_OFFSET));
-  SERIAL_ECHOLNPAIR_P(
+  SERIAL_ECHOLNPGM_P(
     #if IS_CARTESIAN
       LIST_N(DOUBLE(LINEAR_AXES),
         PSTR("  M206 X"), LINEAR_UNIT(home_offset.x),

Marlin/src/gcode/host/M114.cpp

     }
     #if HAS_EXTRUDERS
       if (parser.seen_test('E')) {
-        SERIAL_ECHOLNPAIR("Count E:", stepper.position(E_AXIS));
+        SERIAL_ECHOLNPGM("Count E:", stepper.position(E_AXIS));
         return;
       }
     #endif

Marlin/src/gcode/host/M115.cpp

       apply_motion_limits(cmax);
       const xyz_pos_t lmin = dmin.asLogical(), lmax = dmax.asLogical(),
                       wmin = cmin.asLogical(), wmax = cmax.asLogical();
-      SERIAL_ECHOLNPAIR(
+      SERIAL_ECHOLNPGM(
         "area:{"
           "full:{"
             "min:{x:", lmin.x, ",y:", lmin.y, ",z:", lmin.z, "},"

Marlin/src/gcode/host/M360.cpp

   SERIAL_ECHOPGM("Config:");
   if (pref) SERIAL_ECHOPGM_P(pref);
   if (ind >= 0) { SERIAL_ECHO(ind); SERIAL_CHAR(':'); }
-  SERIAL_ECHOPAIR_P(name, AS_CHAR(':'));
+  SERIAL_ECHOPGM_P(name, AS_CHAR(':'));
 }
 static void config_line(PGM_P const name, const float val, PGM_P const pref=nullptr, const int8_t ind=-1) {
   config_prefix(name, pref, ind);