Add initial code for the base station

Makefile

@@ -1,221 +1,10 @@
-# AVR-GCC Makefile template, derived from the WinAVR template (which
+TARGETS = robot base_station
-# is public domain), believed to be neutral to any flavor of "make"
-# (GNU make, BSD make, SysV make)
 
-SRC_DIR = src
+all:
-BUILD_DIR = build
+	$(foreach var,$(TARGETS),cd $(var) && make && cd ..;)
-INC_DIR = include
-OBJ_DIR = obj
 
-MCU = atmega328p
+debug: $(TARGETS)
-FORMAT = ihex
+	$(foreach var,$(TARGETS),cd $(var) && make debug && cd ..;)
-TARGET = main
-SRC = $(wildcard $(SRC_DIR)/*.c)
-OBJ = $(SRC:$(SRC_DIR)/%.c=$(OBJ_DIR)/%.o)
-LST = $(SRC:$(SRC_DIR)/%.c=$(BUILD_DIR)/%.lst)
-OPT = s
 
-# Name of this Makefile (used for "make depend").
-MAKEFILE = Makefile
-
-# Debugging format.
-# Native formats for AVR-GCC's -g are stabs [default], or dwarf-2.
-# AVR (extended) COFF requires stabs, plus an avr-objcopy run.
-DEBUG = stabs
-
-# Compiler flag to set the C Standard level.
-# c89   - "ANSI" C
-# gnu89 - c89 plus GCC extensions
-# c99   - ISO C99 standard (not yet fully implemented)
-# gnu99 - c99 plus GCC extensions
-CSTANDARD = -std=gnu99
-
-# Place -D or -U options here
-CDEFS = -DF_CPU=16000000L -D__AVR__ -D__AVR_ATmega328P__
-
-# Place -I options here
-CINCS = -I $(INC_DIR)
-
-CDEBUG = -g$(DEBUG)
-CTUNING = -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
-#CEXTRA = -Wa,-adhlns=$(<:.c=.lst)
-CFLAGS = $(CDEBUG) $(CDEFS) $(CINCS) -O$(OPT) $(CSTANDARD) $(CEXTRA)
-
-#ASFLAGS = -Wa,-adhlns=$(<:.S=.lst),-gstabs
-
-ifeq ($(BUILD),debug)
-	CFLAGS += -DDEBUG
-	CFLAGS += -Wall -Wextra -Wformat=2 -Wswitch-default \
-			  -Wcast-align -Wpointer-arith -Wbad-function-cast \
-			  -Wstrict-prototypes -Winline -Wundef -Wnested-externs \
-			  -Wcast-qual -Wshadow -Wwrite-strings -Wconversion \
-			  -Winit-self -Wstrict-aliasing -Wmissing-declarations \
-			  -Wmissing-include-dirs -Wno-unused-parameter -Wuninitialized \
-			  -Wold-style-definition -Wmissing-prototypes -Wunreachable-code \
-			  -Wno-unused-but-set-variable -Wmaybe-uninitialized
-	CINCS += -I/usr/include/simavr
-	#
-endif
-
-#Additional libraries.
-
-# Minimalistic printf version
-PRINTF_LIB_MIN = -Wl,-u,vfprintf -lprintf_min
-
-# Floating point printf version (requires MATH_LIB = -lm below)
-PRINTF_LIB_FLOAT = -Wl,-u,vfprintf -lprintf_flt
-
-PRINTF_LIB =
-
-# Minimalistic scanf version
-SCANF_LIB_MIN = -Wl,-u,vfscanf -lscanf_min
-
-# Floating point + %[ scanf version (requires MATH_LIB = -lm below)
-SCANF_LIB_FLOAT = -Wl,-u,vfscanf -lscanf_flt
-
-SCANF_LIB =
-
-MATH_LIB = -lm
-
-# External memory options
-
-# 64 KB of external RAM, starting after internal RAM (ATmega128!),
-# used for variables (.data/.bss) and heap (malloc()).
-#EXTMEMOPTS = -Wl,--section-start,.data=0x801100,--defsym=__heap_end=0x80ffff
-
-# 64 KB of external RAM, starting after internal RAM (ATmega128!),
-# only used for heap (malloc()).
-#EXTMEMOPTS = -Wl,--defsym=__heap_start=0x801100,--defsym=__heap_end=0x80ffff
-
-EXTMEMOPTS =
-
-#LDMAP = $(LDFLAGS) -Wl,-Map=$(TARGET).map,--cref
-LDFLAGS = $(EXTMEMOPTS) $(LDMAP) $(PRINTF_LIB) $(SCANF_LIB) $(MATH_LIB)
-
-# Programming support using avrdude. Settings and variables.
-
-AVRDUDE_PROGRAMMER = usbasp
-AVRDUDE_PORT = usb
-
-AVRDUDE_WRITE_FLASH = -U flash:w:$(BUILD_DIR)/$(TARGET).hex
-#AVRDUDE_WRITE_EEPROM = -U eeprom:w:$(TARGET).eep
-
-
-# Uncomment the following if you want avrdude's erase cycle counter.
-# Note that this counter needs to be initialized first using -Yn,
-# see avrdude manual.
-#AVRDUDE_ERASE_COUNTER = -y
-
-# Uncomment the following if you do /not/ wish a verification to be
-# performed after programming the device.
-AVRDUDE_NO_VERIFY = -V
-
-# Increase verbosity level.  Please use this when submitting bug
-# reports about avrdude. See <http://savannah.nongnu.org/projects/avrdude>
-# to submit bug reports.
-AVRDUDE_VERBOSE = -v -v
-
-AVRDUDE_BASIC = -p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER)
-AVRDUDE_FLAGS = $(AVRDUDE_BASIC) $(AVRDUDE_NO_VERIFY) $(AVRDUDE_VERBOSE) \
-				$(AVRDUDE_ERASE_COUNTER)
-
-
-CC = avr-gcc
-OBJCOPY = avr-objcopy
-OBJDUMP = avr-objdump
-SIZE = avr-size
-NM = avr-nm
-AVRDUDE = avrdude
-REMOVE = rm -rf
-MV = mv -f
-
-# Combine all necessary flags and optional flags.
-# Add target processor to flags.
-ALL_CFLAGS = -mmcu=$(MCU) $(CFLAGS)
-
-
-# Default target.
-all: build
-
-build: elf hex eep lss sym
-
-elf: $(BUILD_DIR)/$(TARGET).elf
-hex: $(BUILD_DIR)/$(TARGET).hex
-eep: $(BUILD_DIR)/$(TARGET).eep
-lss: $(BUILD_DIR)/$(TARGET).lss
-sym: $(BUILD_DIR)/$(TARGET).sym
-
-
-# Program the device.
-program: $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).eep
-	$(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)
-
-
-debug:
-	make "BUILD=debug"
-
-
-# Convert ELF to COFF for use in debugging / simulating in AVR Studio or VMLAB.
-COFFCONVERT = $(OBJCOPY) --debugging \
-			  --change-section-address .data-0x800000 \
-			  --change-section-address .bss-0x800000 \
-			  --change-section-address .noinit-0x800000 \
-			  --change-section-address .eeprom-0x810000
-
-
-coff: $(BUILD_DIR)/$(TARGET).elf
-	$(COFFCONVERT) -O coff-avr $< $(TARGET).cof
-
-
-extcoff: $(BUILD_DIR)/$(TARGET).elf
-	$(COFFCONVERT) -O coff-ext-avr $< $(TARGET).cof
-
-
-.SUFFIXES: .elf .hex .eep .lss .sym
-
-%.hex: %.elf
-	$(OBJCOPY) -O $(FORMAT) -R .eeprom $< $@
-
-%.eep: %.elf
-	-$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" \
-		--change-section-lma .eeprom=0 -O $(FORMAT) $< $@
-
-# Create extended listing file from ELF output file.
-%.lss: %.elf
-	$(OBJDUMP) -h -S $< > $@
-
-# Create a symbol table from ELF output file.
-%.sym: %.elf
-	$(NM) -n $< > $@
-
-
-
-# Link: create ELF output file from object files.
-.SECONDARY: $(OBJ)
-$(BUILD_DIR)/%.elf: $(OBJ)
-	@mkdir -p $(@D)
-	$(CC) $(ALL_CFLAGS) $^ --output $@ $(LDFLAGS)
-
-
-# Compile: create object files from C source files.
-$(OBJ_DIR)/%.o : $(SRC_DIR)/%.c
-	@mkdir -p $(@D)
-	$(CC) -c $(ALL_CFLAGS) $< -o $@
-
-
-# Target: clean project.
 clean:
-	$(REMOVE) $(BUILD_DIR)/* $(OBJ_DIR)/*
+	$(foreach var,$(TARGETS),cd $(var) && make clean && cd ..;)
-
-depend:
-	if grep '^# DO NOT DELETE' $(MAKEFILE) >/dev/null; \
-		then \
-		sed -e '/^# DO NOT DELETE/,$$d' $(MAKEFILE) > \
-		$(MAKEFILE).$$$$ && \
-		$(MV) $(MAKEFILE).$$$$ $(MAKEFILE); \
-		fi
-	echo '# DO NOT DELETE THIS LINE -- make depend depends on it.' \
-		>> $(MAKEFILE); \
-		$(CC) -M -mmcu=$(MCU) $(CDEFS) $(CINCS) $(SRC) >> $(MAKEFILE)
-
-.PHONY:	all build elf hex eep lss sym program coff extcoff clean depend

base_station/Makefile

@@ -0,0 +1,221 @@
+# AVR-GCC Makefile template, derived from the WinAVR template (which
+# is public domain), believed to be neutral to any flavor of "make"
+# (GNU make, BSD make, SysV make)
+
+SRC_DIR = src
+BUILD_DIR = build
+INC_DIR = include
+OBJ_DIR = obj
+
+MCU = atmega328p
+FORMAT = ihex
+TARGET = main
+SRC = $(wildcard $(SRC_DIR)/*.c)
+OBJ = $(SRC:$(SRC_DIR)/%.c=$(OBJ_DIR)/%.o)
+LST = $(SRC:$(SRC_DIR)/%.c=$(BUILD_DIR)/%.lst)
+OPT = s
+
+# Name of this Makefile (used for "make depend").
+MAKEFILE = Makefile
+
+# Debugging format.
+# Native formats for AVR-GCC's -g are stabs [default], or dwarf-2.
+# AVR (extended) COFF requires stabs, plus an avr-objcopy run.
+DEBUG = stabs
+
+# Compiler flag to set the C Standard level.
+# c89   - "ANSI" C
+# gnu89 - c89 plus GCC extensions
+# c99   - ISO C99 standard (not yet fully implemented)
+# gnu99 - c99 plus GCC extensions
+CSTANDARD = -std=gnu99
+
+# Place -D or -U options here
+CDEFS = -DF_CPU=16000000L -D__AVR__ -D__AVR_ATmega328P__
+
+# Place -I options here
+CINCS = -I $(INC_DIR)
+
+CDEBUG = -g$(DEBUG)
+CTUNING = -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
+#CEXTRA = -Wa,-adhlns=$(<:.c=.lst)
+CFLAGS = $(CDEBUG) $(CDEFS) $(CINCS) -O$(OPT) $(CSTANDARD) $(CEXTRA)
+
+#ASFLAGS = -Wa,-adhlns=$(<:.S=.lst),-gstabs
+
+ifeq ($(BUILD),debug)
+	CFLAGS += -DDEBUG
+	CFLAGS += -Wall -Wextra -Wformat=2 -Wswitch-default \
+			  -Wcast-align -Wpointer-arith -Wbad-function-cast \
+			  -Wstrict-prototypes -Winline -Wundef -Wnested-externs \
+			  -Wcast-qual -Wshadow -Wwrite-strings -Wconversion \
+			  -Winit-self -Wstrict-aliasing -Wmissing-declarations \
+			  -Wmissing-include-dirs -Wno-unused-parameter -Wuninitialized \
+			  -Wold-style-definition -Wmissing-prototypes -Wunreachable-code \
+			  -Wno-unused-but-set-variable -Wmaybe-uninitialized
+	CINCS += -I/usr/include/simavr
+	#
+endif
+
+#Additional libraries.
+
+# Minimalistic printf version
+PRINTF_LIB_MIN = -Wl,-u,vfprintf -lprintf_min
+
+# Floating point printf version (requires MATH_LIB = -lm below)
+PRINTF_LIB_FLOAT = -Wl,-u,vfprintf -lprintf_flt
+
+PRINTF_LIB =
+
+# Minimalistic scanf version
+SCANF_LIB_MIN = -Wl,-u,vfscanf -lscanf_min
+
+# Floating point + %[ scanf version (requires MATH_LIB = -lm below)
+SCANF_LIB_FLOAT = -Wl,-u,vfscanf -lscanf_flt
+
+SCANF_LIB =
+
+MATH_LIB = -lm
+
+# External memory options
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# used for variables (.data/.bss) and heap (malloc()).
+#EXTMEMOPTS = -Wl,--section-start,.data=0x801100,--defsym=__heap_end=0x80ffff
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# only used for heap (malloc()).
+#EXTMEMOPTS = -Wl,--defsym=__heap_start=0x801100,--defsym=__heap_end=0x80ffff
+
+EXTMEMOPTS =
+
+#LDMAP = $(LDFLAGS) -Wl,-Map=$(TARGET).map,--cref
+LDFLAGS = $(EXTMEMOPTS) $(LDMAP) $(PRINTF_LIB) $(SCANF_LIB) $(MATH_LIB)
+
+# Programming support using avrdude. Settings and variables.
+
+AVRDUDE_PROGRAMMER = usbasp
+AVRDUDE_PORT = usb
+
+AVRDUDE_WRITE_FLASH = -U flash:w:$(BUILD_DIR)/$(TARGET).hex
+#AVRDUDE_WRITE_EEPROM = -U eeprom:w:$(TARGET).eep
+
+
+# Uncomment the following if you want avrdude's erase cycle counter.
+# Note that this counter needs to be initialized first using -Yn,
+# see avrdude manual.
+#AVRDUDE_ERASE_COUNTER = -y
+
+# Uncomment the following if you do /not/ wish a verification to be
+# performed after programming the device.
+AVRDUDE_NO_VERIFY = -V
+
+# Increase verbosity level.  Please use this when submitting bug
+# reports about avrdude. See <http://savannah.nongnu.org/projects/avrdude>
+# to submit bug reports.
+AVRDUDE_VERBOSE = -v -v
+
+AVRDUDE_BASIC = -p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER)
+AVRDUDE_FLAGS = $(AVRDUDE_BASIC) $(AVRDUDE_NO_VERIFY) $(AVRDUDE_VERBOSE) \
+				$(AVRDUDE_ERASE_COUNTER)
+
+
+CC = avr-gcc
+OBJCOPY = avr-objcopy
+OBJDUMP = avr-objdump
+SIZE = avr-size
+NM = avr-nm
+AVRDUDE = avrdude
+REMOVE = rm -rf
+MV = mv -f
+
+# Combine all necessary flags and optional flags.
+# Add target processor to flags.
+ALL_CFLAGS = -mmcu=$(MCU) $(CFLAGS)
+
+
+# Default target.
+all: build
+
+build: elf hex eep lss sym
+
+elf: $(BUILD_DIR)/$(TARGET).elf
+hex: $(BUILD_DIR)/$(TARGET).hex
+eep: $(BUILD_DIR)/$(TARGET).eep
+lss: $(BUILD_DIR)/$(TARGET).lss
+sym: $(BUILD_DIR)/$(TARGET).sym
+
+
+# Program the device.
+program: $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).eep
+	$(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)
+
+
+debug:
+	make "BUILD=debug"
+
+
+# Convert ELF to COFF for use in debugging / simulating in AVR Studio or VMLAB.
+COFFCONVERT = $(OBJCOPY) --debugging \
+			  --change-section-address .data-0x800000 \
+			  --change-section-address .bss-0x800000 \
+			  --change-section-address .noinit-0x800000 \
+			  --change-section-address .eeprom-0x810000
+
+
+coff: $(BUILD_DIR)/$(TARGET).elf
+	$(COFFCONVERT) -O coff-avr $< $(TARGET).cof
+
+
+extcoff: $(BUILD_DIR)/$(TARGET).elf
+	$(COFFCONVERT) -O coff-ext-avr $< $(TARGET).cof
+
+
+.SUFFIXES: .elf .hex .eep .lss .sym
+
+%.hex: %.elf
+	$(OBJCOPY) -O $(FORMAT) -R .eeprom $< $@
+
+%.eep: %.elf
+	-$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" \
+		--change-section-lma .eeprom=0 -O $(FORMAT) $< $@
+
+# Create extended listing file from ELF output file.
+%.lss: %.elf
+	$(OBJDUMP) -h -S $< > $@
+
+# Create a symbol table from ELF output file.
+%.sym: %.elf
+	$(NM) -n $< > $@
+
+
+
+# Link: create ELF output file from object files.
+.SECONDARY: $(OBJ)
+$(BUILD_DIR)/%.elf: $(OBJ)
+	@mkdir -p $(@D)
+	$(CC) $(ALL_CFLAGS) $^ --output $@ $(LDFLAGS)
+
+
+# Compile: create object files from C source files.
+$(OBJ_DIR)/%.o : $(SRC_DIR)/%.c
+	@mkdir -p $(@D)
+	$(CC) -c $(ALL_CFLAGS) $< -o $@
+
+
+# Target: clean project.
+clean:
+	$(REMOVE) $(BUILD_DIR)/* $(OBJ_DIR)/*
+
+depend:
+	if grep '^# DO NOT DELETE' $(MAKEFILE) >/dev/null; \
+		then \
+		sed -e '/^# DO NOT DELETE/,$$d' $(MAKEFILE) > \
+		$(MAKEFILE).$$$$ && \
+		$(MV) $(MAKEFILE).$$$$ $(MAKEFILE); \
+		fi
+	echo '# DO NOT DELETE THIS LINE -- make depend depends on it.' \
+		>> $(MAKEFILE); \
+		$(CC) -M -mmcu=$(MCU) $(CDEFS) $(CINCS) $(SRC) >> $(MAKEFILE)
+
+.PHONY:	all build elf hex eep lss sym program coff extcoff clean depend

base_station/include/main.h

@@ -0,0 +1,6 @@
+#ifndef MAIN_H
+#define MAIN_H
+
+#include <stdint.h>
+
+#endif

base_station/src/main.c

@@ -0,0 +1,23 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include "led.h"
+#include "nrf24.h"
+#include "common.h"
+#include "main.h"
+
+#ifdef DEBUG
+#include "debug.h"
+#endif /* DEBUG */
+
+int main(void)
+{
+    init_leds();
+
+    // Use green LED as power LED
+    SET(LED_PORT, LED_GREEN_BIT);
+
+    while (1) { }
+
+    return 0;
+}

robot/Makefile

@@ -0,0 +1,221 @@
+# AVR-GCC Makefile template, derived from the WinAVR template (which
+# is public domain), believed to be neutral to any flavor of "make"
+# (GNU make, BSD make, SysV make)
+
+SRC_DIR = src
+BUILD_DIR = build
+INC_DIR = include
+OBJ_DIR = obj
+
+MCU = atmega328p
+FORMAT = ihex
+TARGET = main
+SRC = $(wildcard $(SRC_DIR)/*.c)
+OBJ = $(SRC:$(SRC_DIR)/%.c=$(OBJ_DIR)/%.o)
+LST = $(SRC:$(SRC_DIR)/%.c=$(BUILD_DIR)/%.lst)
+OPT = s
+
+# Name of this Makefile (used for "make depend").
+MAKEFILE = Makefile
+
+# Debugging format.
+# Native formats for AVR-GCC's -g are stabs [default], or dwarf-2.
+# AVR (extended) COFF requires stabs, plus an avr-objcopy run.
+DEBUG = stabs
+
+# Compiler flag to set the C Standard level.
+# c89   - "ANSI" C
+# gnu89 - c89 plus GCC extensions
+# c99   - ISO C99 standard (not yet fully implemented)
+# gnu99 - c99 plus GCC extensions
+CSTANDARD = -std=gnu99
+
+# Place -D or -U options here
+CDEFS = -DF_CPU=16000000L -D__AVR__ -D__AVR_ATmega328P__
+
+# Place -I options here
+CINCS = -I $(INC_DIR)
+
+CDEBUG = -g$(DEBUG)
+CTUNING = -funsigned-char -funsigned-bitfields -fpack-struct -fshort-enums
+#CEXTRA = -Wa,-adhlns=$(<:.c=.lst)
+CFLAGS = $(CDEBUG) $(CDEFS) $(CINCS) -O$(OPT) $(CSTANDARD) $(CEXTRA)
+
+#ASFLAGS = -Wa,-adhlns=$(<:.S=.lst),-gstabs
+
+ifeq ($(BUILD),debug)
+	CFLAGS += -DDEBUG
+	CFLAGS += -Wall -Wextra -Wformat=2 -Wswitch-default \
+			  -Wcast-align -Wpointer-arith -Wbad-function-cast \
+			  -Wstrict-prototypes -Winline -Wundef -Wnested-externs \
+			  -Wcast-qual -Wshadow -Wwrite-strings -Wconversion \
+			  -Winit-self -Wstrict-aliasing -Wmissing-declarations \
+			  -Wmissing-include-dirs -Wno-unused-parameter -Wuninitialized \
+			  -Wold-style-definition -Wmissing-prototypes -Wunreachable-code \
+			  -Wno-unused-but-set-variable -Wmaybe-uninitialized
+	CINCS += -I/usr/include/simavr
+	#
+endif
+
+#Additional libraries.
+
+# Minimalistic printf version
+PRINTF_LIB_MIN = -Wl,-u,vfprintf -lprintf_min
+
+# Floating point printf version (requires MATH_LIB = -lm below)
+PRINTF_LIB_FLOAT = -Wl,-u,vfprintf -lprintf_flt
+
+PRINTF_LIB =
+
+# Minimalistic scanf version
+SCANF_LIB_MIN = -Wl,-u,vfscanf -lscanf_min
+
+# Floating point + %[ scanf version (requires MATH_LIB = -lm below)
+SCANF_LIB_FLOAT = -Wl,-u,vfscanf -lscanf_flt
+
+SCANF_LIB =
+
+MATH_LIB = -lm
+
+# External memory options
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# used for variables (.data/.bss) and heap (malloc()).
+#EXTMEMOPTS = -Wl,--section-start,.data=0x801100,--defsym=__heap_end=0x80ffff
+
+# 64 KB of external RAM, starting after internal RAM (ATmega128!),
+# only used for heap (malloc()).
+#EXTMEMOPTS = -Wl,--defsym=__heap_start=0x801100,--defsym=__heap_end=0x80ffff
+
+EXTMEMOPTS =
+
+#LDMAP = $(LDFLAGS) -Wl,-Map=$(TARGET).map,--cref
+LDFLAGS = $(EXTMEMOPTS) $(LDMAP) $(PRINTF_LIB) $(SCANF_LIB) $(MATH_LIB)
+
+# Programming support using avrdude. Settings and variables.
+
+AVRDUDE_PROGRAMMER = usbasp
+AVRDUDE_PORT = usb
+
+AVRDUDE_WRITE_FLASH = -U flash:w:$(BUILD_DIR)/$(TARGET).hex
+#AVRDUDE_WRITE_EEPROM = -U eeprom:w:$(TARGET).eep
+
+
+# Uncomment the following if you want avrdude's erase cycle counter.
+# Note that this counter needs to be initialized first using -Yn,
+# see avrdude manual.
+#AVRDUDE_ERASE_COUNTER = -y
+
+# Uncomment the following if you do /not/ wish a verification to be
+# performed after programming the device.
+AVRDUDE_NO_VERIFY = -V
+
+# Increase verbosity level.  Please use this when submitting bug
+# reports about avrdude. See <http://savannah.nongnu.org/projects/avrdude>
+# to submit bug reports.
+AVRDUDE_VERBOSE = -v -v
+
+AVRDUDE_BASIC = -p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER)
+AVRDUDE_FLAGS = $(AVRDUDE_BASIC) $(AVRDUDE_NO_VERIFY) $(AVRDUDE_VERBOSE) \
+				$(AVRDUDE_ERASE_COUNTER)
+
+
+CC = avr-gcc
+OBJCOPY = avr-objcopy
+OBJDUMP = avr-objdump
+SIZE = avr-size
+NM = avr-nm
+AVRDUDE = avrdude
+REMOVE = rm -rf
+MV = mv -f
+
+# Combine all necessary flags and optional flags.
+# Add target processor to flags.
+ALL_CFLAGS = -mmcu=$(MCU) $(CFLAGS)
+
+
+# Default target.
+all: build
+
+build: elf hex eep lss sym
+
+elf: $(BUILD_DIR)/$(TARGET).elf
+hex: $(BUILD_DIR)/$(TARGET).hex
+eep: $(BUILD_DIR)/$(TARGET).eep
+lss: $(BUILD_DIR)/$(TARGET).lss
+sym: $(BUILD_DIR)/$(TARGET).sym
+
+
+# Program the device.
+program: $(BUILD_DIR)/$(TARGET).hex $(BUILD_DIR)/$(TARGET).eep
+	$(AVRDUDE) $(AVRDUDE_FLAGS) $(AVRDUDE_WRITE_FLASH) $(AVRDUDE_WRITE_EEPROM)
+
+
+debug:
+	make "BUILD=debug"
+
+
+# Convert ELF to COFF for use in debugging / simulating in AVR Studio or VMLAB.
+COFFCONVERT = $(OBJCOPY) --debugging \
+			  --change-section-address .data-0x800000 \
+			  --change-section-address .bss-0x800000 \
+			  --change-section-address .noinit-0x800000 \
+			  --change-section-address .eeprom-0x810000
+
+
+coff: $(BUILD_DIR)/$(TARGET).elf
+	$(COFFCONVERT) -O coff-avr $< $(TARGET).cof
+
+
+extcoff: $(BUILD_DIR)/$(TARGET).elf
+	$(COFFCONVERT) -O coff-ext-avr $< $(TARGET).cof
+
+
+.SUFFIXES: .elf .hex .eep .lss .sym
+
+%.hex: %.elf
+	$(OBJCOPY) -O $(FORMAT) -R .eeprom $< $@
+
+%.eep: %.elf
+	-$(OBJCOPY) -j .eeprom --set-section-flags=.eeprom="alloc,load" \
+		--change-section-lma .eeprom=0 -O $(FORMAT) $< $@
+
+# Create extended listing file from ELF output file.
+%.lss: %.elf
+	$(OBJDUMP) -h -S $< > $@
+
+# Create a symbol table from ELF output file.
+%.sym: %.elf
+	$(NM) -n $< > $@
+
+
+
+# Link: create ELF output file from object files.
+.SECONDARY: $(OBJ)
+$(BUILD_DIR)/%.elf: $(OBJ)
+	@mkdir -p $(@D)
+	$(CC) $(ALL_CFLAGS) $^ --output $@ $(LDFLAGS)
+
+
+# Compile: create object files from C source files.
+$(OBJ_DIR)/%.o : $(SRC_DIR)/%.c
+	@mkdir -p $(@D)
+	$(CC) -c $(ALL_CFLAGS) $< -o $@
+
+
+# Target: clean project.
+clean:
+	$(REMOVE) $(BUILD_DIR)/* $(OBJ_DIR)/*
+
+depend:
+	if grep '^# DO NOT DELETE' $(MAKEFILE) >/dev/null; \
+		then \
+		sed -e '/^# DO NOT DELETE/,$$d' $(MAKEFILE) > \
+		$(MAKEFILE).$$$$ && \
+		$(MV) $(MAKEFILE).$$$$ $(MAKEFILE); \
+		fi
+	echo '# DO NOT DELETE THIS LINE -- make depend depends on it.' \
+		>> $(MAKEFILE); \
+		$(CC) -M -mmcu=$(MCU) $(CDEFS) $(CINCS) $(SRC) >> $(MAKEFILE)
+
+.PHONY:	all build elf hex eep lss sym program coff extcoff clean depend

robot/include/common.h

@@ -0,0 +1,12 @@
+#ifndef COMMON_H
+#define COMMON_H
+
+#include <stdint.h>
+
+#define BIT(mask)        (1 << (mask))
+#define SET(var, mask)   ((var) |= (uint8_t)BIT(mask))
+#define CLR(var, mask)   ((var) &= (uint8_t)~(BIT(mask)))
+#define CHK(var, mask)   ((var) &  (uint8_t)BIT(mask))
+#define TOG(var, mask)   ((var) ^= (uint8_t)BIT(mask))
+
+#endif /* COMMON_H */

robot/include/debug.h

@@ -0,0 +1,16 @@
+#ifndef DEBUG_H
+#define DEBUG_H
+
+#include <avr/io.h>
+#include <avr/avr_mcu_section.h>
+
+AVR_MCU(F_CPU, "atmega328p");
+const struct avr_mmcu_vcd_trace_t _mytrace[]  _MMCU_ = {
+    { AVR_MCU_VCD_SYMBOL("DDRD"), .what = (void *) &DDRD, },
+    { AVR_MCU_VCD_SYMBOL("TCCR0A"), .what = (void *) &TCCR0A, },
+    { AVR_MCU_VCD_SYMBOL("TCCR0B"), .what = (void *) &TCCR0B, },
+    { AVR_MCU_VCD_SYMBOL("OCR0A"), .what = (void *) &OCR0A, },
+    { AVR_MCU_VCD_SYMBOL("OCR0B"), .what = (void *) &OCR0B, },
+};
+
+#endif /* DEBUG_H */

robot/include/led.h

@@ -0,0 +1,11 @@
+#ifndef LED_H
+#define LED_H
+
+#define LED_DDR         DDRD
+#define LED_PORT        PORTD
+#define LED_GREEN_BIT   PD3
+#define LED_BLUE_BIT    PD4
+
+void init_leds(void);
+
+#endif /* LED_H */

robot/include/nRF24L01.h

@@ -0,0 +1,130 @@
+/*
+    Copyright (c) 2007 Stefan Engelke <mbox@stefanengelke.de>
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation
+    files (the "Software"), to deal in the Software without
+    restriction, including without limitation the rights to use, copy,
+    modify, merge, publish, distribute, sublicense, and/or sell copies
+    of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+
+    $Id$
+*/
+
+/* Memory Map */
+#define CONFIG      0x00
+#define EN_AA       0x01
+#define EN_RXADDR   0x02
+#define SETUP_AW    0x03
+#define SETUP_RETR  0x04
+#define RF_CH       0x05
+#define RF_SETUP    0x06
+#define STATUS      0x07
+#define OBSERVE_TX  0x08
+#define CD          0x09
+#define RX_ADDR_P0  0x0A
+#define RX_ADDR_P1  0x0B
+#define RX_ADDR_P2  0x0C
+#define RX_ADDR_P3  0x0D
+#define RX_ADDR_P4  0x0E
+#define RX_ADDR_P5  0x0F
+#define TX_ADDR     0x10
+#define RX_PW_P0    0x11
+#define RX_PW_P1    0x12
+#define RX_PW_P2    0x13
+#define RX_PW_P3    0x14
+#define RX_PW_P4    0x15
+#define RX_PW_P5    0x16
+#define FIFO_STATUS 0x17
+#define DYNPD       0x1C
+
+/* Bit Mnemonics */
+
+/* configuratio nregister */
+#define MASK_RX_DR  6
+#define MASK_TX_DS  5
+#define MASK_MAX_RT 4
+#define EN_CRC      3
+#define CRCO        2
+#define PWR_UP      1
+#define PRIM_RX     0
+
+/* enable auto acknowledgment */
+#define ENAA_P5     5
+#define ENAA_P4     4
+#define ENAA_P3     3
+#define ENAA_P2     2
+#define ENAA_P1     1
+#define ENAA_P0     0
+
+/* enable rx addresses */
+#define ERX_P5      5
+#define ERX_P4      4
+#define ERX_P3      3
+#define ERX_P2      2
+#define ERX_P1      1
+#define ERX_P0      0
+
+/* setup of address width */
+#define AW          0 /* 2 bits */
+
+/* setup of auto re-transmission */
+#define ARD         4 /* 4 bits */
+#define ARC         0 /* 4 bits */
+
+/* RF setup register */
+#define PLL_LOCK    4
+#define RF_DR       3
+#define RF_PWR      1 /* 2 bits */
+
+/* general status register */
+#define RX_DR       6
+#define TX_DS       5
+#define MAX_RT      4
+#define RX_P_NO     1 /* 3 bits */
+#define TX_FULL     0
+
+/* transmit observe register */
+#define PLOS_CNT    4 /* 4 bits */
+#define ARC_CNT     0 /* 4 bits */
+
+/* fifo status */
+#define TX_REUSE    6
+#define FIFO_FULL   5
+#define TX_EMPTY    4
+#define RX_FULL     1
+#define RX_EMPTY    0
+
+/* dynamic length */
+#define DPL_P0      0
+#define DPL_P1      1
+#define DPL_P2      2
+#define DPL_P3      3
+#define DPL_P4      4
+#define DPL_P5      5
+
+/* Instruction Mnemonics */
+#define R_REGISTER    0x00 /* last 4 bits will indicate reg. address */
+#define W_REGISTER    0x20 /* last 4 bits will indicate reg. address */
+#define REGISTER_MASK 0x1F
+#define R_RX_PAYLOAD  0x61
+#define W_TX_PAYLOAD  0xA0
+#define FLUSH_TX      0xE1
+#define FLUSH_RX      0xE2
+#define REUSE_TX_PL   0xE3
+#define ACTIVATE      0x50
+#define R_RX_PL_WID   0x60
+#define NOP           0xFF

robot/include/nrf24.h

@@ -0,0 +1,116 @@
+/*
+* ----------------------------------------------------------------------------
+* “THE COFFEEWARE LICENSE” (Revision 1):
+* <ihsan@kehribar.me> wrote this file. As long as you retain this notice you
+* can do whatever you want with this stuff. If we meet some day, and you think
+* this stuff is worth it, you can buy me a coffee in return.
+* -----------------------------------------------------------------------------
+* This library is based on this library:
+*   https://github.com/aaronds/arduino-nrf24l01
+* Which is based on this library:
+*   http://www.tinkerer.eu/AVRLib/nRF24L01
+* -----------------------------------------------------------------------------
+*/
+#ifndef NRF24
+#define NRF24
+
+#include "nRF24L01.h"
+#include <stdint.h>
+
+#define LOW 0
+#define HIGH 1
+
+#define nrf24_ADDR_LEN 5
+#define nrf24_CONFIG ((1<<EN_CRC)|(0<<CRCO))
+
+#define NRF24_TRANSMISSON_OK 0
+#define NRF24_MESSAGE_LOST   1
+
+/* adjustment functions */
+void    nrf24_init();
+void    nrf24_rx_address(uint8_t *adr);
+void    nrf24_tx_address(uint8_t *adr);
+void    nrf24_config(uint8_t channel, uint8_t pay_length);
+
+/* state check functions */
+uint8_t nrf24_dataReady();
+uint8_t nrf24_isSending();
+uint8_t nrf24_getStatus();
+uint8_t nrf24_rxFifoEmpty();
+
+/* core TX / RX functions */
+void    nrf24_send(uint8_t *value);
+void    nrf24_getData(uint8_t *data);
+
+/* use in dynamic length mode */
+uint8_t nrf24_payloadLength();
+
+/* post transmission analysis */
+uint8_t nrf24_lastMessageStatus();
+uint8_t nrf24_retransmissionCount();
+
+/* Returns the payload length */
+uint8_t nrf24_payload_length();
+
+/* power management */
+void    nrf24_powerUpRx();
+void    nrf24_powerUpTx();
+void    nrf24_powerDown();
+
+/* low level interface ... */
+uint8_t spi_transfer(uint8_t tx);
+void    nrf24_transmitSync(uint8_t *dataout, uint8_t len);
+void    nrf24_transferSync(uint8_t *dataout, uint8_t *datain, uint8_t len);
+void    nrf24_configRegister(uint8_t reg, uint8_t value);
+void    nrf24_readRegister(uint8_t reg, uint8_t *value, uint8_t len);
+void    nrf24_writeRegister(uint8_t reg, uint8_t *value, uint8_t len);
+
+/* -------------------------------------------------------------------------- */
+/* You should implement the platform spesific functions in your code */
+/* -------------------------------------------------------------------------- */
+
+/* -------------------------------------------------------------------------- */
+/* In this function you should do the following things:
+ *    - Set MISO pin input
+ *    - Set MOSI pin output
+ *    - Set SCK pin output
+ *    - Set CSN pin output
+ *    - Set CE pin output     */
+/* -------------------------------------------------------------------------- */
+extern void nrf24_setupPins();
+
+/* -------------------------------------------------------------------------- */
+/* nrf24 CE pin control function
+ *    - state:1 => Pin HIGH
+ *    - state:0 => Pin LOW     */
+/* -------------------------------------------------------------------------- */
+extern void nrf24_ce_digitalWrite(uint8_t state);
+
+/* -------------------------------------------------------------------------- */
+/* nrf24 CE pin control function
+ *    - state:1 => Pin HIGH
+ *    - state:0 => Pin LOW     */
+/* -------------------------------------------------------------------------- */
+extern void nrf24_csn_digitalWrite(uint8_t state);
+
+/* -------------------------------------------------------------------------- */
+/* nrf24 SCK pin control function
+ *    - state:1 => Pin HIGH
+ *    - state:0 => Pin LOW     */
+/* -------------------------------------------------------------------------- */
+extern void nrf24_sck_digitalWrite(uint8_t state);
+
+/* -------------------------------------------------------------------------- */
+/* nrf24 MOSI pin control function
+ *    - state:1 => Pin HIGH
+ *    - state:0 => Pin LOW     */
+/* -------------------------------------------------------------------------- */
+extern void nrf24_mosi_digitalWrite(uint8_t state);
+
+/* -------------------------------------------------------------------------- */
+/* nrf24 MISO pin read function
+* - returns: Non-zero if the pin is high */
+/* -------------------------------------------------------------------------- */
+extern uint8_t nrf24_miso_digitalRead();
+
+#endif

robot/include/servos.h

@@ -9,10 +9,13 @@
 
 #define SERVO_MIN       930 // (us). Go backwards
 #define SERVO_MAX       1930 // (us). Go forwards
-#define SERVO_MID       (SERVO_MIN + SERVO_MAX) / 2 // Stop
+#define SERVO_MID       (SERVO_MIN + SERVO_MAX) / 2 // (us). Stop
-#define PWM_PERIOD      16384 // (1000000 / F_CPU) * PRESCALER * 256) / F_CPU (us)
 
-#define US2TIMER0(us)   (255 * (uint32_t)us) / PWM_PERIOD
+#define PRESCALER       1024L
+#define PWM_CLOCK       F_CPU / (256 * PRESCALER)
+#define PWM_PERIOD_US   1000000 / PWM_CLOCK
+
+#define US2TIMER0(us)   (255 * (uint32_t)us) / PWM_PERIOD_US
 
 
 void init_servos(void);

robot/src/led.c

@@ -0,0 +1,9 @@
+#include <avr/io.h>
+#include "common.h"
+#include "led.h"
+
+void init_leds(void)
+{
+    SET(LED_DDR, LED_GREEN_BIT);
+    SET(LED_DDR, LED_BLUE_BIT);
+}

robot/src/main.c

@@ -37,7 +37,7 @@ int main(void)
     // Use green LED as power LED
     SET(LED_PORT, LED_GREEN_BIT);
 
-    /* run_servos(); */
+    run_servos();
     /* read_temp(); */
     while (1) {
         uint16_t distance_int_cm = read_sonar();

robot/src/nrf24.c

@@ -0,0 +1,339 @@
+/*
+* ----------------------------------------------------------------------------
+* “THE COFFEEWARE LICENSE” (Revision 1):
+* <ihsan@kehribar.me> wrote this file. As long as you retain this notice you
+* can do whatever you want with this stuff. If we meet some day, and you think
+* this stuff is worth it, you can buy me a coffee in return.
+* -----------------------------------------------------------------------------
+* This library is based on this library:
+*   https://github.com/aaronds/arduino-nrf24l01
+* Which is based on this library:
+*   http://www.tinkerer.eu/AVRLib/nRF24L01
+* -----------------------------------------------------------------------------
+*/
+#include "nrf24.h"
+
+uint8_t payload_len;
+
+/* init the hardware pins */
+void nrf24_init()
+{
+    nrf24_setupPins();
+    nrf24_ce_digitalWrite(LOW);
+    nrf24_csn_digitalWrite(HIGH);
+}
+
+/* configure the module */
+void nrf24_config(uint8_t channel, uint8_t pay_length)
+{
+    /* Use static payload length ... */
+    payload_len = pay_length;
+
+    // Set RF channel
+    nrf24_configRegister(RF_CH, channel);
+
+    // Set length of incoming payload
+    nrf24_configRegister(RX_PW_P0, 0x00); // Auto-ACK pipe ...
+    nrf24_configRegister(RX_PW_P1, payload_len); // Data payload pipe
+    nrf24_configRegister(RX_PW_P2, 0x00); // Pipe not used
+    nrf24_configRegister(RX_PW_P3, 0x00); // Pipe not used
+    nrf24_configRegister(RX_PW_P4, 0x00); // Pipe not used
+    nrf24_configRegister(RX_PW_P5, 0x00); // Pipe not used
+
+    // 1 Mbps, TX gain: 0dbm
+    nrf24_configRegister(RF_SETUP, (0 << RF_DR) | ((0x03) << RF_PWR));
+
+    // CRC enable, 1 byte CRC length
+    nrf24_configRegister(CONFIG, nrf24_CONFIG);
+
+    // Auto Acknowledgment
+    nrf24_configRegister(EN_AA, (1 << ENAA_P0) | (1 << ENAA_P1) | (0 << ENAA_P2) | (0 << ENAA_P3) | (0 << ENAA_P4) | (0 << ENAA_P5));
+
+    // Enable RX addresses
+    nrf24_configRegister(EN_RXADDR, (1 << ERX_P0) | (1 << ERX_P1) | (0 << ERX_P2) | (0 << ERX_P3) | (0 << ERX_P4) | (0 << ERX_P5));
+
+    // Auto retransmit delay: 1000 us and Up to 15 retransmit trials
+    nrf24_configRegister(SETUP_RETR, (0x04 << ARD) | (0x0F << ARC));
+
+    // Dynamic length configurations: No dynamic length
+    nrf24_configRegister(DYNPD, (0 << DPL_P0) | (0 << DPL_P1) | (0 << DPL_P2) | (0 << DPL_P3) | (0 << DPL_P4) | (0 << DPL_P5));
+
+    // Start listening
+    nrf24_powerUpRx();
+}
+
+/* Set the RX address */
+void nrf24_rx_address(uint8_t *adr)
+{
+    nrf24_ce_digitalWrite(LOW);
+    nrf24_writeRegister(RX_ADDR_P1, adr, nrf24_ADDR_LEN);
+    nrf24_ce_digitalWrite(HIGH);
+}
+
+/* Returns the payload length */
+uint8_t nrf24_payload_length()
+{
+    return payload_len;
+}
+
+/* Set the TX address */
+void nrf24_tx_address(uint8_t *adr)
+{
+    /* RX_ADDR_P0 must be set to the sending addr for auto ack to work. */
+    nrf24_writeRegister(RX_ADDR_P0, adr, nrf24_ADDR_LEN);
+    nrf24_writeRegister(TX_ADDR, adr, nrf24_ADDR_LEN);
+}
+
+/* Checks if data is available for reading */
+/* Returns 1 if data is ready ... */
+uint8_t nrf24_dataReady()
+{
+    // See note in getData() function - just checking RX_DR isn't good enough
+    uint8_t status = nrf24_getStatus();
+
+    // We can short circuit on RX_DR, but if it's not set, we still need
+    // to check the FIFO for any pending packets
+    if (status & (1 << RX_DR)) {
+        return 1;
+    }
+
+    return !nrf24_rxFifoEmpty();;
+}
+
+/* Checks if receive FIFO is empty or not */
+uint8_t nrf24_rxFifoEmpty()
+{
+    uint8_t fifoStatus;
+
+    nrf24_readRegister(FIFO_STATUS, &fifoStatus, 1);
+
+    return (fifoStatus & (1 << RX_EMPTY));
+}
+
+/* Returns the length of data waiting in the RX fifo */
+uint8_t nrf24_payloadLength()
+{
+    uint8_t status;
+    nrf24_csn_digitalWrite(LOW);
+    spi_transfer(R_RX_PL_WID);
+    status = spi_transfer(0x00);
+    nrf24_csn_digitalWrite(HIGH);
+    return status;
+}
+
+/* Reads payload bytes into data array */
+void nrf24_getData(uint8_t *data)
+{
+    /* Pull down chip select */
+    nrf24_csn_digitalWrite(LOW);
+
+    /* Send cmd to read rx payload */
+    spi_transfer(R_RX_PAYLOAD);
+
+    /* Read payload */
+    nrf24_transferSync(data, data, payload_len);
+
+    /* Pull up chip select */
+    nrf24_csn_digitalWrite(HIGH);
+
+    /* Reset status register */
+    nrf24_configRegister(STATUS, (1 << RX_DR));
+}
+
+/* Returns the number of retransmissions occured for the last message */
+uint8_t nrf24_retransmissionCount()
+{
+    uint8_t rv;
+    nrf24_readRegister(OBSERVE_TX, &rv, 1);
+    rv = rv & 0x0F;
+    return rv;
+}
+
+// Sends a data package to the default address. Be sure to send the correct
+// amount of bytes as configured as payload on the receiver.
+void nrf24_send(uint8_t *value)
+{
+    /* Go to Standby-I first */
+    nrf24_ce_digitalWrite(LOW);
+
+    /* Set to transmitter mode , Power up if needed */
+    nrf24_powerUpTx();
+
+    /* Do we really need to flush TX fifo each time ? */
+#if 1
+    /* Pull down chip select */
+    nrf24_csn_digitalWrite(LOW);
+
+    /* Write cmd to flush transmit FIFO */
+    spi_transfer(FLUSH_TX);
+
+    /* Pull up chip select */
+    nrf24_csn_digitalWrite(HIGH);
+#endif
+
+    /* Pull down chip select */
+    nrf24_csn_digitalWrite(LOW);
+
+    /* Write cmd to write payload */
+    spi_transfer(W_TX_PAYLOAD);
+
+    /* Write payload */
+    nrf24_transmitSync(value, payload_len);
+
+    /* Pull up chip select */
+    nrf24_csn_digitalWrite(HIGH);
+
+    /* Start the transmission */
+    nrf24_ce_digitalWrite(HIGH);
+}
+
+uint8_t nrf24_isSending()
+{
+    uint8_t status;
+
+    /* read the current status */
+    status = nrf24_getStatus();
+
+    /* if sending successful (TX_DS) or max retries exceded (MAX_RT). */
+    if ((status & ((1 << TX_DS)  | (1 << MAX_RT)))) {
+        return 0; /* false */
+    }
+
+    return 1; /* true */
+
+}
+
+uint8_t nrf24_getStatus()
+{
+    uint8_t rv;
+    nrf24_csn_digitalWrite(LOW);
+    rv = spi_transfer(NOP);
+    nrf24_csn_digitalWrite(HIGH);
+    return rv;
+}
+
+uint8_t nrf24_lastMessageStatus()
+{
+    uint8_t rv;
+
+    rv = nrf24_getStatus();
+
+    /* Transmission went OK */
+    if ((rv & ((1 << TX_DS)))) {
+        return NRF24_TRANSMISSON_OK;
+    }
+    /* Maximum retransmission count is reached */
+    /* Last message probably went missing ... */
+    else if ((rv & ((1 << MAX_RT)))) {
+        return NRF24_MESSAGE_LOST;
+    }
+    /* Probably still sending ... */
+    else {
+        return 0xFF;
+    }
+}
+
+void nrf24_powerUpRx()
+{
+    nrf24_csn_digitalWrite(LOW);
+    spi_transfer(FLUSH_RX);
+    nrf24_csn_digitalWrite(HIGH);
+
+    nrf24_configRegister(STATUS, (1 << RX_DR) | (1 << TX_DS) | (1 << MAX_RT));
+
+    nrf24_ce_digitalWrite(LOW);
+    nrf24_configRegister(CONFIG, nrf24_CONFIG | ((1 << PWR_UP) | (1 << PRIM_RX)));
+    nrf24_ce_digitalWrite(HIGH);
+}
+
+void nrf24_powerUpTx()
+{
+    nrf24_configRegister(STATUS, (1 << RX_DR) | (1 << TX_DS) | (1 << MAX_RT));
+
+    nrf24_configRegister(CONFIG, nrf24_CONFIG | ((1 << PWR_UP) | (0 << PRIM_RX)));
+}
+
+void nrf24_powerDown()
+{
+    nrf24_ce_digitalWrite(LOW);
+    nrf24_configRegister(CONFIG, nrf24_CONFIG);
+}
+
+/* software spi routine */
+uint8_t spi_transfer(uint8_t tx)
+{
+    uint8_t i = 0;
+    uint8_t rx = 0;
+
+    nrf24_sck_digitalWrite(LOW);
+
+    for (i = 0; i < 8; i++) {
+
+        if (tx & (1 << (7 - i))) {
+            nrf24_mosi_digitalWrite(HIGH);
+        } else {
+            nrf24_mosi_digitalWrite(LOW);
+        }
+
+        nrf24_sck_digitalWrite(HIGH);
+
+        rx = rx << 1;
+        if (nrf24_miso_digitalRead()) {
+            rx |= 0x01;
+        }
+
+        nrf24_sck_digitalWrite(LOW);
+
+    }
+
+    return rx;
+}
+
+/* send and receive multiple bytes over SPI */
+void nrf24_transferSync(uint8_t *dataout, uint8_t *datain, uint8_t len)
+{
+    uint8_t i;
+
+    for (i = 0; i < len; i++) {
+        datain[i] = spi_transfer(dataout[i]);
+    }
+
+}
+
+/* send multiple bytes over SPI */
+void nrf24_transmitSync(uint8_t *dataout, uint8_t len)
+{
+    uint8_t i;
+
+    for (i = 0; i < len; i++) {
+        spi_transfer(dataout[i]);
+    }
+
+}
+
+/* Clocks only one byte into the given nrf24 register */
+void nrf24_configRegister(uint8_t reg, uint8_t value)
+{
+    nrf24_csn_digitalWrite(LOW);
+    spi_transfer(W_REGISTER | (REGISTER_MASK & reg));
+    spi_transfer(value);
+    nrf24_csn_digitalWrite(HIGH);
+}
+
+/* Read single register from nrf24 */
+void nrf24_readRegister(uint8_t reg, uint8_t *value, uint8_t len)
+{
+    nrf24_csn_digitalWrite(LOW);
+    spi_transfer(R_REGISTER | (REGISTER_MASK & reg));
+    nrf24_transferSync(value, value, len);
+    nrf24_csn_digitalWrite(HIGH);
+}
+
+/* Write to a single register of nrf24 */
+void nrf24_writeRegister(uint8_t reg, uint8_t *value, uint8_t len)
+{
+    nrf24_csn_digitalWrite(LOW);
+    spi_transfer(W_REGISTER | (REGISTER_MASK & reg));
+    nrf24_transmitSync(value, len);
+    nrf24_csn_digitalWrite(HIGH);
+}

robot/src/radioPinFunctions.c

@@ -0,0 +1,74 @@
+/*
+* ----------------------------------------------------------------------------
+* “THE COFFEEWARE LICENSE” (Revision 1):
+* <ihsan@kehribar.me> wrote this file. As long as you retain this notice you
+* can do whatever you want with this stuff. If we meet some day, and you think
+* this stuff is worth it, you can buy me a coffee in return.
+* -----------------------------------------------------------------------------
+* Please define your platform spesific functions in this file ...
+* -----------------------------------------------------------------------------
+*/
+
+#include <avr/io.h>
+#include "common.h"
+
+#define REG         DDRB
+#define PORT        PORTB
+#define PIN         PINB
+#define PIN_CE      PB0
+#define PIN_CSN     PB1
+#define PIN_SCK     PB5
+#define PIN_MOSI    PB3
+#define PIN_MISO    PB4
+
+/* ------------------------------------------------------------------------- */
+void nrf24_setupPins(void)
+{
+    SET(REG, PIN_CE);
+    SET(REG, PIN_CSN);
+    SET(REG, PIN_SCK);
+    SET(REG, PIN_MOSI);
+    CLR(REG, PIN_MISO);
+}
+/* ------------------------------------------------------------------------- */
+void nrf24_ce_digitalWrite(uint8_t state)
+{
+    if (state) {
+        SET(PORT, PIN_CE);
+    } else {
+        CLR(PORT, PIN_CE);
+    }
+}
+/* ------------------------------------------------------------------------- */
+void nrf24_csn_digitalWrite(uint8_t state)
+{
+    if (state) {
+        SET(PORT, PIN_CSN);
+    } else {
+        CLR(PORT, PIN_CSN);
+    }
+}
+/* ------------------------------------------------------------------------- */
+void nrf24_sck_digitalWrite(uint8_t state)
+{
+    if (state) {
+        SET(PORT, PIN_SCK);
+    } else {
+        CLR(PORT, PIN_SCK);
+    }
+}
+/* ------------------------------------------------------------------------- */
+void nrf24_mosi_digitalWrite(uint8_t state)
+{
+    if (state) {
+        SET(PORT, PIN_MOSI);
+    } else {
+        CLR(PORT, PIN_MOSI);
+    }
+}
+/* ------------------------------------------------------------------------- */
+uint8_t nrf24_miso_digitalRead(void)
+{
+    return CHK(PIN, PIN_MISO);
+}
+/* ------------------------------------------------------------------------- */

robot/src/servos.c

@@ -15,9 +15,9 @@ void init_servos(void)
     SET(TCCR0A, WGM00);
     SET(TCCR0A, WGM01);
 
-    // Prescaler. clkPWM = clkIO / 64
+    // Prescaler = 1024
     SET(TCCR0B, CS00);
-    SET(TCCR0B, CS01);
+    SET(TCCR0B, CS02);
 }
 
 void run_servos(void)

robot/src/sonar.c

@@ -5,7 +5,7 @@
 #include "led.h"
 
 volatile uint32_t trig_counter;
-volatile uint32_t no_of_ticks;
+uint32_t no_of_ticks;
 
 void init_sonar(void)
 {
@@ -36,19 +36,15 @@ uint16_t read_sonar(void)
     sei();
     // Count cycles until ECHO goes low
     while (CHK(ECHO_PIN, ECHO_BIT)) {
-        if (no_of_ticks + TCNT1 > SONAR_TIMEOUT) {
+        ++no_of_ticks;
+        if (no_of_ticks > SONAR_TIMEOUT) {
             return SONAR_ERROR;
         }
     }
     TCCR1B = 0x00;
     cli();
 
-    no_of_ticks += TCNT1;
 
     return (uint16_t)(no_of_ticks / (CYCLES_PER_US * 58));
 }
 
-ISR(TIMER1_OVF_vect)
-{
-    no_of_ticks += TIMER_MAX;
-}