Split up SPI and CC2500 code.

include/iface_cc2500.h → include/cc2500.h

@@ -124,10 +124,17 @@ enum {
 #define CC2500_LQI_CRC_OK_BM                   0x80
 #define CC2500_LQI_EST_BM                      0x7F
 
-//void CC2500_WriteReg(u8 addr, u8 data);
-//u8 CC2500_ReadReg(u8 addr);
-//void CC2500_Reset();
-//void CC2500_Strobe(u8 cmd);
-//void CC2500_WriteData(u8 *packet, u8 length);
-//void CC2500_ReadData(u8 *dpbuffer, int len);
+void cc2500ReadFifo(uint8_t *dpbuffer, int len);
+void cc2500WriteFifo(uint8_t *dpbuffer, uint8_t len);
+
+void cc2500ReadRegisterMulti(uint8_t address, uint8_t data[], uint8_t length);
+void cc2500WriteRegisterMulti(uint8_t address, const uint8_t data[], uint8_t length);
+
+unsigned char cc2500ReadReg(unsigned char address);
+void cc2500WriteReg(uint8_t address, uint8_t data);
+
+void cc2500Strobe(uint8_t address);
+void cc2500ResetChip(void);
+
 #endif
+

include/spi.h

@@ -0,0 +1,33 @@
+/*
+ * Bit-Banged SPI routines
+ */
+
+#ifndef _SPI_H
+#define _SPI_H
+
+#include <stdint.h>
+#include <avr/io.h>
+
+#define SCK_on PORTB |= PB4
+#define SCK_off PORTB &= ~(PB4)
+
+#define MO_on PORTB |= PB3
+#define MO_off PORTB &= ~(PB3)
+
+#define CS_on PORTB |= PB1
+#define CS_off PORTB &= ~(PB1)
+
+#define MI_1 (PINB & PB2) == PB2
+#define MI_0 (PINB & PB2) != PB2
+
+#define GDO_1 (PINB & PB0) == PB0
+#define GDO_0 (PINB & PB0) != PB0
+
+#define NOP() __asm__ __volatile__("nop")
+
+void spi_init(void);
+void spi_write(uint8_t command);
+uint8_t spi_read(void);
+
+#endif
+

makefile

@@ -1,65 +1,66 @@
-MCU = attiny85
-F_CPU = 16000000
-RM = rm -rf
-EXTRAINCDIR = include
-CSTANDARD = gnu99
-
-GCC = avr-gcc
-SIZE = avr-size
-OBJCOPY = avr-objcopy
-OBJDUMP = avr-objdump
-AVRDUDE = avrdude
-
-SRC = src/cc2500_BB_SPI.c
-SRC += src/frsky_arduino_rx_complete.c
-
-OBJ = $(SRC:.c=.o)
-
-CARGS = -mmcu=$(MCU)
-CARGS += -I$(EXTRAINCDIR)
-CARGS += -Os
-CARGS += -funsigned-char
-CARGS += -funsigned-bitfields
-CARGS += -fpack-struct
-CARGS += -fshort-enums
-CARGS += -Wall -pedantic -Wstrict-prototypes -Wshadow
-CARGS += -Wpointer-arith -Wcast-qual -Wextra
-CARGS += -Wno-write-strings -Wno-unused-parameter
-CARGS += -std=$(CSTANDARD)
-CARGS += -DF_CPU=$(F_CPU)
-#CARGS += -lm -lprintf_flt
-CARGS += -ffunction-sections
-
-LINKER = -Wl,--relax
-#LINKER = -Wl,--relax,-u,vfprintf,-lm,-lprintf_flt,-u,vfscanf,-lscanf_flt
-#LINKER += -Wl,--defsym=__heap_start=0x802200,--defsym=__heap_end=0x80ffff
-#LINKER += -Wl,-gc-sections
-
-PROGRAMMER = avrisp2
-ISPPORT = usb
-
-TARGET = rx
-
-all: $(TARGET).hex
-
-%.o: %.c
-	$(GCC) -c $< -o $@ $(CARGS)
-
-$(TARGET).elf: $(OBJ)
-	$(GCC) $(CARGS) $(OBJ) --output $@ $(LINKER) -Wl,-Map -Wl,$(@:.elf=.map)
-	$(SIZE) --mcu=$(MCU) -C $@
-
-$(TARGET).hex: $(TARGET).elf
-	$(OBJCOPY) -O ihex $< $@
-	$(OBJDUMP) -h -S $< > $(@:.hex=.lss)
-
-program: $(TARGET).hex
-	$(AVRDUDE) -p $(MCU) -c $(PROGRAMMER) -P $(ISPPORT) -e -U $(TARGET).hex
-
-clean:
-	$(RM) $(OBJ)
-	$(RM) *.o
-	$(RM) *.elf
-	$(RM) *.hex
-	$(RM) *.lss
-	$(RM) *.map
+MCU = attiny85
+F_CPU = 16000000
+RM = rm -rf
+EXTRAINCDIR = include
+CSTANDARD = gnu99
+
+GCC = avr-gcc
+SIZE = avr-size
+OBJCOPY = avr-objcopy
+OBJDUMP = avr-objdump
+AVRDUDE = avrdude
+
+SRC = src/spi.c
+SRC += src/cc2500.c
+SRC += src/frsky_arduino_rx_complete.c
+
+OBJ = $(SRC:.c=.o)
+
+CARGS = -mmcu=$(MCU)
+CARGS += -I$(EXTRAINCDIR)
+CARGS += -Os
+CARGS += -funsigned-char
+CARGS += -funsigned-bitfields
+CARGS += -fpack-struct
+CARGS += -fshort-enums
+CARGS += -Wall -pedantic -Wstrict-prototypes -Wshadow
+CARGS += -Wpointer-arith -Wcast-qual -Wextra
+CARGS += -Wno-write-strings -Wno-unused-parameter
+CARGS += -std=$(CSTANDARD)
+CARGS += -DF_CPU=$(F_CPU)
+#CARGS += -lm -lprintf_flt
+CARGS += -ffunction-sections
+
+LINKER = -Wl,--relax
+#LINKER = -Wl,--relax,-u,vfprintf,-lm,-lprintf_flt,-u,vfscanf,-lscanf_flt
+#LINKER += -Wl,--defsym=__heap_start=0x802200,--defsym=__heap_end=0x80ffff
+#LINKER += -Wl,-gc-sections
+
+PROGRAMMER = avrisp2
+ISPPORT = usb
+
+TARGET = rx
+
+all: $(TARGET).hex
+
+%.o: %.c
+	$(GCC) -c $< -o $@ $(CARGS)
+
+$(TARGET).elf: $(OBJ)
+	$(GCC) $(CARGS) $(OBJ) --output $@ $(LINKER) -Wl,-Map -Wl,$(@:.elf=.map)
+	$(SIZE) --mcu=$(MCU) -C $@
+
+$(TARGET).hex: $(TARGET).elf
+	$(OBJCOPY) -O ihex $< $@
+	$(OBJDUMP) -h -S $< > $(@:.hex=.lss)
+
+program: $(TARGET).hex
+	$(AVRDUDE) -p $(MCU) -c $(PROGRAMMER) -P $(ISPPORT) -e -U $(TARGET).hex
+
+clean:
+	$(RM) $(OBJ)
+	$(RM) *.o
+	$(RM) *.elf
+	$(RM) *.hex
+	$(RM) *.lss
+	$(RM) *.map

src/cc2500.c

@@ -0,0 +1,72 @@
+/*
+ * CC2500 helper routines
+ */
+
+#include <util/delay.h>
+#include "spi.h"
+#include "cc2500.h"
+
+void cc2500ReadFifo(uint8_t *dpbuffer, int len) {
+    cc2500ReadRegisterMulti(CC2500_3F_RXFIFO | CC2500_READ_BURST, dpbuffer, len);
+}
+
+void cc2500ReadRegisterMulti(uint8_t address, uint8_t data[], uint8_t length) {
+    CS_off;
+    spi_write(address);
+    for (uint8_t i = 0; i < length; i++) {
+        data[i] = spi_read();
+    }
+    CS_on;
+}
+
+void cc2500WriteRegisterMulti(uint8_t address, const uint8_t data[], uint8_t length) {
+    CS_off;
+    spi_write(CC2500_WRITE_BURST | address);
+    for (uint8_t i = 0; i < length; i++) {
+        spi_write(data[i]);
+    }
+    CS_on;
+}
+
+void cc2500WriteFifo(uint8_t *dpbuffer, uint8_t len) {
+    cc2500Strobe(CC2500_SFTX); // 0x3B
+    cc2500WriteRegisterMulti(CC2500_3F_TXFIFO, dpbuffer, len);
+    cc2500Strobe(CC2500_STX); // 0x35
+}
+
+void cc2500WriteReg(uint8_t address, uint8_t data) {
+    CS_off;
+    spi_write(address);
+    NOP();
+    spi_write(data);
+    CS_on;
+}
+
+unsigned char cc2500ReadReg(unsigned char address) {
+    uint8_t result;
+    CS_off;
+    address |= 0x80; // bit 7 =1 for reading
+    spi_write(address);
+    result = spi_read();
+    CS_on;
+    return result;
+}
+
+void cc2500Strobe(uint8_t address) {
+    CS_off;
+    spi_write(address);
+    CS_on;
+}
+
+void cc2500ResetChip(void) {
+    // Toggle chip select signal
+    CS_on;
+    _delay_us(30);
+    CS_off;
+    _delay_us(30);
+    CS_on;
+    _delay_us(45);
+    cc2500Strobe(CC2500_SRES);
+    _delay_ms(100);
+}
+

src/cc2500_BB_SPI.c

@@ -1,122 +0,0 @@
-//-------------------------------
-//-------------------------------
-//CC2500 SPI routines
-//-------------------------------
-//-------------------------------
-#include <util/delay.h>
-
-void cc2500_readFifo(uint8_t *dpbuffer, int len)
-{
-    ReadRegisterMulti(CC2500_3F_RXFIFO | CC2500_READ_BURST, dpbuffer, len);
-}
-
-//----------------------
-static void ReadRegisterMulti(uint8_t address, uint8_t data[], uint8_t length)
-{
-    unsigned char i;
-
-    CS_off;
-    _spi_write(address);
-    for (i = 0; i < length; i++) {
-        data[i] = _spi_read();
-    }
-    CS_on;
-}
-
-//*********************************************
-
-void CC2500_WriteRegisterMulti(uint8_t address, const uint8_t data[], uint8_t length)
-{
-    CS_off;
-    _spi_write(CC2500_WRITE_BURST | address);
-    for (int i = 0; i < length; i++) {
-        _spi_write(data[i]);
-    }
-    CS_on;
-}
-
-void cc2500_writeFifo(uint8_t *dpbuffer, uint8_t len)
-{
-    cc2500_strobe(CC2500_SFTX);//0x3B
-    CC2500_WriteRegisterMulti(CC2500_3F_TXFIFO, dpbuffer, len);
-    cc2500_strobe(CC2500_STX);//0x35
-}
-
-//--------------------------------------
-void _spi_write(uint8_t command)
-{
-    uint8_t n = 8;
-    SCK_off;//SCK start low
-    MO_off;
-    while (n--) {
-        if (command & 0x80)
-            MO_on;
-        else
-            MO_off;
-        SCK_on;
-        NOP();
-        SCK_off;
-        command = command << 1;
-    }
-    MO_on;
-}
-
-//----------------------------
-void cc2500_writeReg(uint8_t address, uint8_t data)  //same as 7105
-{
-    CS_off;
-    _spi_write(address);
-    NOP();
-    _spi_write(data);
-    CS_on;
-}
-
-uint8_t _spi_read(void)
-{
-    uint8_t result;
-    uint8_t i;
-    result = 0;
-    for (i = 0; i < 8; i++) {
-        if (MI_1) ///
-            result = (result << 1) | 0x01;
-        else
-            result = result << 1;
-        SCK_on;
-        NOP();
-        SCK_off;
-        NOP();
-    }
-    return result;
-}
-
-//--------------------------------------------
-unsigned char cc2500_readReg(unsigned char address)
-{
-    uint8_t result;
-    CS_off;
-    address |= 0x80; //bit 7 =1 for reading
-    _spi_write(address);
-    result = _spi_read();
-    CS_on;
-    return (result);
-}
-//------------------------
-void cc2500_strobe(uint8_t address)
-{
-    CS_off;
-    _spi_write(address);
-    CS_on;
-}
-//------------------------
-void cc2500_resetChip(void)
-{
-    // Toggle chip select signal
-    CS_on;
-    _delay_us(30);
-    CS_off;
-    _delay_us(30);
-    CS_on;
-    _delay_us(45);
-    cc2500_strobe(CC2500_SRES);
-    _delay_ms(100);
-}

src/spi.c

@@ -0,0 +1,59 @@
+/*
+ * Bit-Banged SPI routines
+ */
+
+#include "spi.h"
+
+void spi_init(void) {
+    DDRB |= (1 << PB2);  // SI output
+    DDRB &= ~(1 << PB3); // SO input
+    DDRB |= (1 << PB4);  // SCLK output
+    DDRB |= (1 << PB1);  // CS output
+    DDRB &= ~(1 << PB0); // GDO0 input
+
+    SCK_off;
+    MO_off;
+    CS_on;
+}
+
+void spi_write(uint8_t command) {
+    SCK_off; //SCK start low
+    MO_off;
+
+    uint8_t n = 8;
+    while (n--) {
+        if (command & 0x80) {
+            MO_on;
+        } else {
+            MO_off;
+        }
+
+        SCK_on;
+        NOP();
+        SCK_off;
+
+        command = command << 1;
+    }
+
+    MO_on;
+}
+
+uint8_t spi_read(void) {
+    uint8_t result = 0;
+
+    for (uint8_t i = 0; i < 8; i++) {
+        if (MI_1) {
+            result = (result << 1) | 0x01;
+        } else {
+            result = result << 1;
+        }
+
+        SCK_on;
+        NOP();
+        SCK_off;
+        NOP();
+    }
+
+    return result;
+}
+