Experimental Physics and
Industrial Control System

Marty Kraimer <[email protected]> · Tue, 21 Oct 1997 07:56:27 -0500

Benjamin Franksen wrote:
> 
> Hi again,
> 
> I fear the aoRecord is 'infected' by the same kind of disease, as one
> can see by looking into the init_record() and convert() functions. In
> the first case the solution is the same as in the aiRecord, replace
> 
>         val = pai->rval + pai->roff;
> 
> in init_record() by
> 
>         val = (double)pai->rval + (double)pai->roff;
>

This one I remembered to do.

> In the second case (convert()) it goes the other way around: First val
> is streched according to eslo as in
> 
>         value = (value - pao->egul) / pao->eslo;
> 
> Afterwards roff is subtracted:
> 
>         pao->rval -= pao->roff;
> 
> As in the aiRecord, if egul and eguf are assuming 32 bit raw values,
> this can lead to an overflow. Proposed solution: replace the last 4
> lines of convert():
> 
>         if (value >= 0.0) pao->rval = value + 0.5;
>         else    pao->rval = value - 0.5;
>         pao->rval -= pao->roff;
>         return;
> 
> by these three:
> 
>         if (value >= 0.0) pao->rval = value - pao->roff + 0.5;
>         else    pao->rval = value - pao->roff- 0.5;
>         return;
>

This one I did not remember.

I will make the change

Marty Kraimer

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System