[A83] Re: interrupt loop


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[A83] Re: interrupt loop




I'm not really sure about that, but if somebody would like to test this out.
(I don't have a real calc at the moment.)

If you set up the following interrupt routine and your calc locks up, a DI
is NOT necessary. If it keeps running, a DI IS necessary to prevent other
interrupts.

intStart:

    ex     af,af'
    bit    0,(iy+33)
    ret    nz
    set    0,(iy+33)
    ex     af,af'
    halt
    res    0,(iy+33)
    jp     0039h

intEnd:


tijl


----- Original Message -----
From: "Michael Vincent" <hookman@worldnet.att.net>
To: <assembly-83@lists.ticalc.org>
Sent: Wednesday, December 05, 2001 00:14
Subject: [A83] Re: interrupt loop


>
> If you're using your own IM 2 routine, you have to DI to disable
interrupts
> at the beginning to prevent this..Then you EI at the end of your routine.
>
> Michael Vincent
> Detached Solutions - www.detacheds.com
> Radical Software - www.radicalsoft.org
>
> ----- Original Message -----
> From: "Tijl Coosemans" <tijl@ulyssis.org>
> To: <assembly-83@lists.ticalc.org>
> Sent: Tuesday, December 04, 2001 2:23 PM
> Subject: [A83] Re: interrupt loop
>
>
> >
> > During an interrupt, interrupts are disabled, so you don't have to worry
> > about that.
> >
> > ----- Original Message -----
> > From: "SUCKER from the old days" <sucker_pvn@hotmail.com>
> > To: <assembly-83@lists.ticalc.org>
> > Sent: Tuesday, December 04, 2001 21:48
> > Subject: [A83] interrupt loop
> >
> >
> > >
> > > What happens if a standalone interrupt program has
> > > such a large piece of interrupt code that before it's
> > > finished the z80 does another interrupt call? (So the loop restarts)
> > >
> > >          SUCKER
> > >
> > > _________________________________________________________________
> > > Get your FREE download of MSN Explorer at
> http://explorer.msn.com/intl.asp
> > >
> > >
> >
> >
> >
>
>





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