Re: Floating point calculations on 16 uC


db wrote:
> Hi,
>
> I'm doing floating point calculations on a Fujitsu MB90F474 16bit uC.
> All float calculations are done in the main loop context. Sometimes the
> result returns a garbage value. This seems to happen only when
> interrupts are enabled. Note that there are no globals or shared data
> involved.
>
> If anyone has had similar problems please let me know. Any advice when
> using floating point calculations would be appreciated.
>
> Regards
> Dieter

You dont say what kind of garbage your getting. Stack overruns are easy
to detect as it will trash your fixed variables starting from the
highest 1 (check your map file). Sometimes you can have problems with
far/near pointers. Compile useing the large model and see if your
problem dissapears. If all else fails disable each interrupt
individualy.

.

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