Re: [avr-gcc-list] Problem with interrupt handler?

[Clemens Gerlach]

On Fri, Oct 19, 2001 at 02:54:19AM -0500, Chris Baugher wrote:

> > It looks like for some reason your code is not linked with c-runtime code 
> > (something like crt2313.o). Interrupt vector initializations and jump to 
> > main is done there.
> 
> A few minutes after writing that mail I started thinking along those
> lines. This is the sequence of commands I use for compiling etc..
> 
> 
> fluke:~/dro$ make
> avr-gcc  -mmcu=at90s2313 -O2 -Wall -S -Wstrict-prototypes \
> -I/usr/local/avr/include -c dro.c
> dro.c:55: warning: return type of `main' is not `int'
> avr-as -gstabs -mmcu=at90s2313 -ahlms=dro.lst dro.s -o dro.o \
> -I/usr/local/avr/lib/
> avr-ld  -Map dro.map -o dro dro.o
> avr-objcopy -g --output-target=ihex dro dro.ihex
> fluke:~/dro$
> 
> 
> Does this look reasonable?

you do not link the startup code (crts2313.o). the interrupt jump table and
other setup code (e.g stack initialisation) is located there.

simply use avr-gcc to link your object files (e.g.):

avr-gcc -mmcu=at90s4433 -Wall -O9 -o flow.o -c flow.c    # no -S here
avr-gcc -mmcu=at90s4433 -Wall -O9 -o main.elf flow.o     # use to call linker
                                                         # also links runtime 
code
avr-objcopy -O srec main.elf main.srec                   # maybe change to ihex


your milage may vary.

clemens