CC = avr-gcc
OBJECTS = Ringbuffer.o TWISlave.o TWIMaster.o
F_CPU ?= 16000000L
CFLAGS += -Wall -O3 -std=gnu99 -mmcu=atmega8 -DF_CPU=$(F_CPU)

all: keyboard.hex

keyboard.elf: $(OBJECTS) main.o
	$(CC) $(CFLAGS) -o $@.new $^ && mv $@.new $@

TWISlave.o: TWISlave.c TWISlave.h Ringbuffer.h
TWIMaster.o: TWIMaster.c TWIMaster.h Ringbuffer.h
Ringbuffer.o: Ringbuffer.c Ringbuffer.h
main.o: main.c TWISlave.h

%.hex: %.elf
	avr-objcopy -j .text -j .data -O ihex $^ $@

clean:
	rm -f keyboard.hex keyboard.elf $(OBJECTS) main.o

distclean: clean
upload: keyboard.hex
	sudo avrdude -p m8 -c usbtiny -U flash:w:$<