overworked the serial responses. Quite difficult, since many texts are Pronterface protocol.

Marlin/EEPROMwrite.h

   char ver2[4]=EEPROM_VERSION;
   i=EEPROM_OFFSET;
   EEPROM_writeAnything(i,ver2); // validate data
-   ECHOLN("Settings Stored");
+   SERIAL_ECHOLN("Settings Stored");
 
 }
 
   char stored_ver[4];
   char ver[4]=EEPROM_VERSION;
   EEPROM_readAnything(i,stored_ver); //read stored version
-//  ECHOLN("Version: [" << ver << "] Stored version: [" << stored_ver << "]");
+//  SERIAL_ECHOLN("Version: [" << ver << "] Stored version: [" << stored_ver << "]");
   if ((!def)&&(strncmp(ver,stored_ver,3)==0)) {   // version number match
       EEPROM_readAnything(i,axis_steps_per_unit);  
       EEPROM_readAnything(i,max_feedrate);  
       EEPROM_readAnything(i,Ki);
       EEPROM_readAnything(i,Kd);
 
-      ECHOLN("Stored settings retreived:");
+      SERIAL_ECHOLN("Stored settings retreived:");
   }
   else {
     float tmp1[]=DEFAULT_AXIS_STEPS_PER_UNIT;
     mintravelfeedrate=DEFAULT_MINTRAVELFEEDRATE;
     max_xy_jerk=DEFAULT_XYJERK;
     max_z_jerk=DEFAULT_ZJERK;
-    ECHOLN("Using Default settings:");
+    SERIAL_ECHOLN("Using Default settings:");
   }
-  ECHOLN("Steps per unit:");
-  ECHOLN("   M92 X"   <<_FLOAT(axis_steps_per_unit[0],3) << " Y" <<  _FLOAT(axis_steps_per_unit[1],3) << " Z" << _FLOAT(axis_steps_per_unit[2],3) << " E" << _FLOAT(axis_steps_per_unit[3],3));
-  ECHOLN("Maximum feedrates (mm/s):");
-  ECHOLN("   M203 X"  <<_FLOAT(max_feedrate[0]/60,2)<<" Y" << _FLOAT(max_feedrate[1]/60,2) << " Z" << _FLOAT(max_feedrate[2]/60,2) << " E" << _FLOAT(max_feedrate[3]/60,2));
-  ECHOLN("Maximum Acceleration (mm/s2):");
-  ECHOLN("   M201 X"  <<_FLOAT(max_acceleration_units_per_sq_second[0],0) << " Y" << _FLOAT(max_acceleration_units_per_sq_second[1],0) << " Z" << _FLOAT(max_acceleration_units_per_sq_second[2],0) << " E" << _FLOAT(max_acceleration_units_per_sq_second[3],0));
-  ECHOLN("Acceleration: S=acceleration, T=retract acceleration");
-  ECHOLN("   M204 S"  <<_FLOAT(acceleration,2) << " T" << _FLOAT(retract_acceleration,2));
-  ECHOLN("Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum xY jerk (mm/s),  Z=maximum Z jerk (mm/s)");
-  ECHOLN("   M205 S"  <<_FLOAT(minimumfeedrate/60,2) << " T" << _FLOAT(mintravelfeedrate/60,2) << " B" << _FLOAT(minsegmenttime,2) << " X" << _FLOAT(max_xy_jerk/60,2) << " Z" << _FLOAT(max_z_jerk/60,2));
+  SERIAL_ECHOLN("Steps per unit:");
+  SERIAL_ECHOLN("   M92 X"   <<_FLOAT(axis_steps_per_unit[0],3) << " Y" <<  _FLOAT(axis_steps_per_unit[1],3) << " Z" << _FLOAT(axis_steps_per_unit[2],3) << " E" << _FLOAT(axis_steps_per_unit[3],3));
+  SERIAL_ECHOLN("Maximum feedrates (mm/s):");
+  SERIAL_ECHOLN("   M203 X"  <<_FLOAT(max_feedrate[0]/60,2)<<" Y" << _FLOAT(max_feedrate[1]/60,2) << " Z" << _FLOAT(max_feedrate[2]/60,2) << " E" << _FLOAT(max_feedrate[3]/60,2));
+  SERIAL_ECHOLN("Maximum Acceleration (mm/s2):");
+  SERIAL_ECHOLN("   M201 X"  <<_FLOAT(max_acceleration_units_per_sq_second[0],0) << " Y" << _FLOAT(max_acceleration_units_per_sq_second[1],0) << " Z" << _FLOAT(max_acceleration_units_per_sq_second[2],0) << " E" << _FLOAT(max_acceleration_units_per_sq_second[3],0));
+  SERIAL_ECHOLN("Acceleration: S=acceleration, T=retract acceleration");
+  SERIAL_ECHOLN("   M204 S"  <<_FLOAT(acceleration,2) << " T" << _FLOAT(retract_acceleration,2));
+  SERIAL_ECHOLN("Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum xY jerk (mm/s),  Z=maximum Z jerk (mm/s)");
+  SERIAL_ECHOLN("   M205 S"  <<_FLOAT(minimumfeedrate/60,2) << " T" << _FLOAT(mintravelfeedrate/60,2) << " B" << _FLOAT(minsegmenttime,2) << " X" << _FLOAT(max_xy_jerk/60,2) << " Z" << _FLOAT(max_z_jerk/60,2));
 #ifdef PIDTEMP
-  ECHOLN("PID settings:");
-  ECHOLN("   M301 P"  << _FLOAT(Kp,3) << " I" << _FLOAT(Ki,3) << " D" << _FLOAT(Kd,3));  
+  SERIAL_ECHOLN("PID settings:");
+  SERIAL_ECHOLN("   M301 P"  << _FLOAT(Kp,3) << " I" << _FLOAT(Ki,3) << " D" << _FLOAT(Kd,3));  
 #endif
   
 }  

Marlin/Makefile

 UPLOAD_PROTOCOL = stk500v2
 BUILD_MCU = atmega2560
 BUILD_F_CPU = 16000000L
+TERM=bash
 
 # getting undefined reference to `__cxa_pure_virtual'
 #~ [http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1254180518 Arduino Forum - Makefile]

Marlin/Marlin.h

 #include <WProgram.h>
 #include "fastio.h"
 
-
-#define ECHO(x) Serial << "echo: " << x;
-#define ECHOLN(x) Serial << "echo: "<<x<<endl;
+#include "streaming.h"
+#define SERIAL_ECHO(x) Serial << "echo: " << x;
+#define SERIAL_ECHOLN(x) Serial << "echo: "<<x<<endl;
+#define SERIAL_ERROR(x) Serial << "echo: ERROR: " << x;
+#define SERIAL_ERRORLN(x) Serial << "echo: ERROR: " << x<<endl;
 
 void get_command();
 void process_commands();
 //void plan_set_position(float x, float y, float z, float e);
 //void st_wake_up();
 //void st_synchronize();
-void enquecommand(const char *cmd);
+void enquecommand(const char *cmd); //put an ascii command at the end of the current buffer.
 
 
 #ifndef CRITICAL_SECTION_START

Marlin/Marlin.pde

 // M27  - Report SD print status
 // M28  - Start SD write (M28 filename.g)
 // M29  - Stop SD write
+// M30  - Output time since last M109 or SD card start to serial
 // M42  - Change pin status via gcode
 // M80  - Turn on Power Supply
 // M81  - Turn off Power Supply
 int16_t n;
 unsigned long autostart_atmillis=0;
 
-void initsd(){
+void initsd()
+{
   sdactive = false;
 #if SDSS >- 1
   if(root.isOpen())
     root.close();
-  if (!card.init(SPI_FULL_SPEED,SDSS)){
+  if (!card.init(SPI_FULL_SPEED,SDSS))
+  {
     //if (!card.init(SPI_HALF_SPEED,SDSS))
-    Serial.println("SD init fail");
+    SERIAL_ECHOLN("SD init fail");
   }
   else if (!volume.init(&card))
-    Serial.println("volume.init failed");
+  {
+    SERIAL_ERRORLN("volume.init failed");
+  }
   else if (!root.openRoot(&volume)) 
-    Serial.println("openRoot failed");
+  {
+    SERIAL_ERRORLN("openRoot failed");
+  }
   else 
-	{
+  {
     sdactive = true;
-		Serial.println("SD card ok");
-	}
+    SERIAL_ECHOLN("SD card ok");
+  }
 #endif //SDSS
 }
 
   //Serial.println(begin);
   file.write(begin);
   if (file.writeError){
-    Serial.println("error writing to file");
+    SERIAL_ERRORLN("error writing to file");
   }
 }
 #endif //SDSUPPORT
   {
     //this is dangerous if a mixing of serial and this happsens
     strcpy(&(cmdbuffer[bufindw][0]),cmd);
-    Serial.print("en:");Serial.println(cmdbuffer[bufindw]);
+    SERIAL_ECHOLN("enqueing \""<<cmdbuffer[bufindw]<<"\"");
     bufindw= (bufindw + 1)%BUFSIZE;
     buflen += 1;
   }
 { 
 	
   Serial.begin(BAUDRATE);
-  ECHOLN("Marlin "<<version_string);
+  SERIAL_ECHOLN("Marlin "<<version_string);
   Serial.println("start");
 #if defined FANCY_LCD || defined SIMPLE_LCD
   lcd_init();
       sdpos = file.curPosition();
       if(sdpos >= filesize){
         sdmode = false;
-        Serial.println("Done printing file");
-				stoptime=millis();
-				char time[30];
-				unsigned long t=(stoptime-starttime)/1000;
-				int sec,min;
-				min=t/60;
-				sec=t%60;
-				sprintf(time,"%i min, %i sec",min,sec);
-				Serial.println(time);
-				LCD_MESSAGE(time);
-				checkautostart(true);
+        Serial.println("echo: Done printing file");
+	stoptime=millis();
+	char time[30];
+	unsigned long t=(stoptime-starttime)/1000;
+	int sec,min;
+	min=t/60;
+	sec=t%60;
+	sprintf(time,"echo: %i min, %i sec",min,sec);
+	Serial.println(time);
+	LCD_MESSAGE(time);
+	checkautostart(true);
       }
       if(!serial_count) return; //if empty line
       cmdbuffer[bufindw][serial_count] = 0; //terminate string
     case 24: //M24 - Start SD print
       if(sdactive){
         sdmode = true;
-				starttime=millis();
+	starttime=millis();
       }
       break;
     case 25: //M25 - Pause SD print
       //processed in write to file routine above
       //savetosd = false;
       break;
-		case 30:
-		{
-			stoptime=millis();
-				char time[30];
-				unsigned long t=(stoptime-starttime)/1000;
-				int sec,min;
-				min=t/60;
-				sec=t%60;
-				sprintf(time,"%i min, %i sec",min,sec);
-				Serial.println(time);
-				LCD_MESSAGE(time);
-                }
-                                break;
+    case 30: //M30 take time since the start of the SD print or an M109 command
+    {
+      stoptime=millis();
+      char time[30];
+      unsigned long t=(stoptime-starttime)/1000;
+      int sec,min;
+      min=t/60;
+      sec=t%60;
+      sprintf(time,"echo: time needed %i min, %i sec",min,sec);
+      Serial.println(time);
+      LCD_MESSAGE(time);
+    }
+    break;
 #endif //SDSUPPORT
       case 42: //M42 -Change pin status via gcode
         if (code_seen('S'))
             Serial.println();
           #endif
         #else
-          Serial.println("No thermistors - no temp");
+          Serial.println("echo: No thermistors - no temp");
         #endif
         return;
         //break;
               }
               #endif //TEMP_RESIDENCY_TIME
             }
-            LCD_MESSAGE("Marlin ready.");
+            LCD_MESSAGE("Heating done.");
+	    starttime=millis();
           }
           break;
       case 190: // M190 - Wait bed for heater to reach target.
       if(code_seen('P')) Kp = code_value();
       if(code_seen('I')) Ki = code_value()*PID_dT;
       if(code_seen('D')) Kd = code_value()/PID_dT;
-//      ECHOLN("Kp "<<_FLOAT(Kp,2));
-//      ECHOLN("Ki "<<_FLOAT(Ki/PID_dT,2));
-//      ECHOLN("Kd "<<_FLOAT(Kd*PID_dT,2));
+//      SERIAL_ECHOLN("Kp "<<_FLOAT(Kp,2));
+//      SERIAL_ECHOLN("Ki "<<_FLOAT(Ki/PID_dT,2));
+//      SERIAL_ECHOLN("Kd "<<_FLOAT(Kd*PID_dT,2));
 
 //      temp_iState_min = 0.0;
 //      if (Ki!=0) {
     }
   }
   else{
-    Serial.println("Unknown command:");
-    Serial.println(cmdbuffer[bufindr]);
+    Serial.print("echo: Unknown command:\"");
+    Serial.print(cmdbuffer[bufindr]);
+    Serial.println("\"");
   }
 
   ClearToSend();
   disable_e();
   
   if(PS_ON_PIN > -1) pinMode(PS_ON_PIN,INPUT);
-  Serial.println("!! Printer halted. kill() called !!");
+  SERIAL_ERRORLN("Printer halted. kill() called !!");
   while(1); // Wait for reset
 }
 

Marlin/motion_control.cpp

 {      
 //   int acceleration_manager_was_enabled = plan_is_acceleration_manager_enabled();
 //   plan_set_acceleration_manager_enabled(false); // disable acceleration management for the duration of the arc
-  Serial.println("mc_arc");
+  SERIAL_ECHOLN("mc_arc.");
   float center_axis0 = position[axis_0] + offset[axis_0];
   float center_axis1 = position[axis_1] + offset[axis_1];
   float linear_travel = target[axis_linear] - position[axis_linear];

Marlin/stepper.cpp

 // It pops blocks from the block_buffer and executes them by pulsing the stepper pins appropriately. 
 ISR(TIMER1_COMPA_vect)
 {        
-  if(busy){ Serial.print(*(unsigned short *)OCR1A); Serial.println(" BUSY");
+  if(busy){ SERIAL_ERRORLN(*(unsigned short *)OCR1A<< " ISR overtaking itself.");
     return; 
   } // The busy-flag is used to avoid reentering this interrupt
 

Marlin/temperature.cpp

     }
 #endif //PID_OPENLOOP
 #ifdef PID_DEBUG
-     Serial.print(" Input ");
-     Serial.print(pid_input);
-     Serial.print(" Output ");
-     Serial.print(pid_output);    
-     Serial.print(" pTerm ");
-     Serial.print(pTerm); 
-     Serial.print(" iTerm ");
-     Serial.print(iTerm); 
-     Serial.print(" dTerm ");
-     Serial.print(dTerm); 
-     Serial.println();
+     SERIAL_ECHOLN(" PIDDEBUG Input "<<pid_input<<" Output "<<pid_output" pTerm "<<pTerm<<" iTerm "<<iTerm<<" dTerm "<<dTerm); 
+     
 #endif //PID_DEBUG
     analogWrite(HEATER_0_PIN, pid_output);
 #endif //PIDTEMP
             temp_count++;
             break;
     default:
-            Serial.println("!! Temp measurement error !!");
+            SERIAL_ERRORLN("Temp measurement error!");
             break;
   }
     
     if(current_raw[TEMPSENSOR_HOTEND_0] >= maxttemp_0) {
       target_raw[TEMPSENSOR_HOTEND_0] = 0;
       analogWrite(HEATER_0_PIN, 0);
-      Serial.println("!! Temperature extruder 0 switched off. MAXTEMP triggered !!");
+      SERIAL_ERRORLN("Temperature extruder 0 switched off. MAXTEMP triggered !!");
       kill();
     }
   #endif
       target_raw[TEMPSENSOR_HOTEND_1] = 0;
     if(current_raw[2] >= maxttemp_1) {
       analogWrite(HEATER_2_PIN, 0);
-      Serial.println("!! Temperature extruder 1 switched off. MAXTEMP triggered !!");
+      SERIAL_ERRORLN("Temperature extruder 1 switched off. MAXTEMP triggered !!");
       kill()
     }
   #endif
     if(current_raw[TEMPSENSOR_HOTEND_0] <= minttemp_0) {
       target_raw[TEMPSENSOR_HOTEND_0] = 0;
       analogWrite(HEATER_0_PIN, 0);
-      Serial.println("!! Temperature extruder 0 switched off. MINTEMP triggered !!");
+      SERIAL_ERRORLN("Temperature extruder 0 switched off. MINTEMP triggered !!");
       kill();
     }
   #endif
     if(current_raw[TEMPSENSOR_HOTEND_1] <= minttemp_1) {
       target_raw[TEMPSENSOR_HOTEND_1] = 0;
       analogWrite(HEATER_2_PIN, 0);
-      Serial.println("!! Temperature extruder 1 switched off. MINTEMP triggered !!");
+      SERIAL_ERRORLN("Temperature extruder 1 switched off. MINTEMP triggered !!");
       kill();
     }
   #endif
     if(current_raw[1] <= bed_minttemp) {
       target_raw[1] = 0;
       WRITE(HEATER_1_PIN, 0);
-      Serial.println("!! Temperatur heated bed switched off. MINTEMP triggered !!");
+      SERIAL_ERRORLN("Temperatur heated bed switched off. MINTEMP triggered !!");
       kill();
     }
   #endif
     if(current_raw[1] >= bed_maxttemp) {
       target_raw[1] = 0;
       WRITE(HEATER_1_PIN, 0);
-      Serial.println("!! Temperature heated bed switched off. MAXTEMP triggered !!");
+      SERIAL_ERRORLN("Temperature heated bed switched off. MAXTEMP triggered !!");
       kill();
     }
   #endif

Marlin/ultralcd.pde

       }break;
 #endif
       default: 
-        Serial.println('NEVER say never');
+        SERIAL_ERRORLN("Something is wrong in the MenuStructure.");
       break;
     }
   }
   {
     force_lcd_update=true;
     oldcardstatus=CARDINSERTED;
-    //Serial.println("SD CHANGE");
+    //Serial.println("echo: SD CHANGE");
     if(CARDINSERTED)
     {
       initsd();

Marlin/watchdog.pde

  
     #ifdef RESET_MANUAL
       LCD_MESSAGE("Please Reset!");
-      ECHOLN("echo_: Something is wrong, please turn off the printer.");
+      SERIAL_ERRORLN("Something is wrong, please turn off the printer.");
     #else
       LCD_MESSAGE("Timeout, resetting!");
     #endif