Re: [Sdcc-user] A tale of two interrupts...

[Mario K. <ma...@kl...>]

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On Friday, 14. September 2001 07:27, M.v...@ca... wrote:

> My initial program was just main and serial, trying to get that
> working. Eventually I got it going satisfactorily. The serial
> routines I use are basically a rip-off of the serial.c available at
> the okr site, written by Victoria Welch (who based her code on
> something written for keil).
> ...
> All fine and good.
>
> Then, I tried to add my periodic interrupt. This is when things
> started to go pear-shaped...
>
> The initial version of intr.c used a call-back function passed as a
> function-pointer to the init() routine. But this didn't seem to work,
> so I tried it without, which seemed to work for a little while, but
> also stuffed up other parts of the program...

You probably need reentrancy. And if you use a different register bank
in your ISR, you need to specify this register bank for each
subroutine, you might be calling from interrupt context. In cases like
this, it always is a good idea to inspect the assembly code generated.

BTW, this is NOT a problem of the compiler, but of the 8051
architecture. IMHO the 8051 architecture, although really fund to
program in asm, is a bad choice for programming C.

73, Mario
- --
Mario Klebsch						ma...@kl...
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