Re: [avr-chat] Mega88 bootloader?

[Bernard Fouché]

Bob Paddock wrote:

> At the end of my bootloader I have:
>
>    __asm__ __volatile__ ("rjmp 0x0000\n\t" ::);
>
>
> The code that seems to be generated is:
>
>     __asm__ __volatile__ ("rjmp 0x0000\n\t" ::);
>     1e1c:    26 cf           rjmp    .-436        ; 0x1c6a
>
> What don't I understand here?  1C6A is obviously not 0x0000.
> 1C6A is my spi_xfer() function.
>
> I'll go with your zero Z, ijmp technique that way I'm sure I will
> end up at zero.

Here we have:

- in Makefile:

   LDFLAGS += -Wl, --defsym=app_start=0

- and in the bootloader itself:

   asm volatile("jmp app_start");

It works well!

Bernard