Re: A86: interrupts

To: assembly-86@lists.ticalc.org
Subject: Re: A86: interrupts
From: Kirk Meyer <_@ibm.net>
Date: Thu, 30 Apr 1998 20:32:56 -0600
Delivered-To: assembly-86-outgoing@towerguard.unix.edu.sollentuna.se
References: <35491D66.3DF511C4@eden.rutgers.edu>
Reply-To: assembly-86@lists.ticalc.org

i see no reason for pushing & poping - there's nothing to be saved if
you disassemble the int handler. if you're using the built-in int
support then you CAN skip the calc's interrupt - at the end, do the
following:

pop hl
exx
ex af,af'
reti

and you should go back to where the interrupt was called from. in this
way the slow-down "feature" of the 86 could be avoided during games.
such a feature would be useful in ase or rascall (hint hint :)

Dux Gregis wrote:
> 
> I have two questions:
> 
> Will the disable interrupt instruction disable the interrupt in
> interrupt mode 2?
> And, if instead of pushing the registers in an interrupt routine you did
> <pop hl>, would you have the program counter in hl from where the
> routine was called?  I don't think this would be possible using the
> regular interrupt because you would destroy the registers, but maybe
> using interrupt mode 2?

-- 

=====================================
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=   Kirk Meyer (mailto:_@ibm.net)   =
= http://www.bigfoot.com/~kirkmeyer =
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=   "Set your affection on things   =
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Follow-Ups:

Re: A86: interrupts

From: Dux Gregis <assets@eden.rutgers.edu>

References:

A86: interrupts

From: Dux Gregis <assets@eden.rutgers.edu>