# required packages: avrdude gcc-avr avr-libc
# the atmega firmware binary to output
TARGET=scale
# to compile
CC=avr-gcc
OBJDUMP=avr-objdump
OBJCOPY=avr-objcopy
CFLAGS=-g -Wall -Werror -O3 -std=c99
# the target
DEVICE=atmega328p
F_CPU=16000000UL
# the flasher
PROGRAMMER=arduino
PORT=/dev/ttyUSB0
# to flash (specially for the arduino, with DTR pulse ot reset)
FLASHER=avrdude -p $(DEVICE) -c $(PROGRAMMER) -P $(PORT) -b 57600 -D
# source files to compile
SRC = $(wildcard *.c)
# header files.
HEADER = $(SRC:.c=.h)
# object files.
OBJ = $(SRC:.c=.o)
# listing files.
LST = $(SRC:.c=.lst)

all: compile $(TARGET).lst flash

reset:
	stty 57600 raw ignbrk hup < $(PORT)

flash: compile reset
	$(FLASHER) -U flash:w:$(TARGET).hex:i

compile: $(TARGET).hex

# compile
%.o: %.c %.h
	$(CC) $(CFLAGS) -I. -mmcu=$(DEVICE) -DF_CPU=$(F_CPU) -c -o $@ $<

# link
%.elf: $(OBJ)
	$(CC) $(CFLAGS) -I. -mmcu=$(DEVICE) -DF_CPU=$(F_CPU) -Wl,-Map=$(TARGET).map,--cref -o $@ $(OBJ)

# extended listing
%.lst: %.elf
	$(OBJDUMP) -h -S $< > $@

# output file
%.hex: %.elf
	$(OBJCOPY) -j .text -j .data -O ihex $< $@

clean:
	rm -f $(TARGET) $(TARGET).hex $(TARGET).elf $(TARGET).lst $(TARGET).map  $(LST) $(OBJ)