AVR-Chat

Hi all,

I've got a program that sends MIDI on an ATtiny2313.

http://ringbreak.dnd.utwente.nl/~mrjb/electro/midisender.c

I've also got a make file, as follows:
CC=avr-gcc
#HEADERS=-I /usr/src/linux-headers-2.6.24-19/include/asm-avr32/
CFLAGS=-g -Os -Wall -mcall-prologues -mmcu=attiny2313 $(HEADERS)
#CFLAGS=-g -Os -Wall -mcall-prologues -mmcu=atmega8 $(HEADERS)
OBJ2HEX=/usr/bin/avr-objcopy
UISP=/usr/local/bin/uisp
TARGET=midisender

program : $(TARGET).hex
         avrdude -c usbtiny -p m8 -e
         avrdude -c usbtiny -p m8 -U flash:w:$(TARGET).hex:i
%.obj : %.o
         $(CC) $(CFLAGS) $< -o $@

%.hex : %.obj
         $(OBJ2HEX) -R .eeprom -O ihex $< $@

clean :
         rm -f *.hex *.obj *.o

I want to use the code with an ATmega8 and have hooked up the
ATmega8 appropriately.

Now for the strange thing: I compiled the source with the
above makefile (for the wrong microcontroller: attiny2313) and
ran it on the ATmega8. It ran just fine.

I then proceeded to add ADC code and found out the Makefile was
wrong. To make sure all was still working, I removed the ADC code
again and compiled for ATmega8. No MIDI output. I commented the
ATmega8 line and restored the ATtiny2313 options, recompiled it
and wrote it to the ATmega8- it worked.

So if I compile it for ATtiny2313 and run it on ATmega8 it works.
But if I compile for ATmega8 and run the same code on ATmega8, I
get no MIDI output.

I'm baffled. Why does my code not work on ATmega8 if I compiled
for the ATmega8?

Thanks in advance,
Marc