Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!dlyons
From: dlyons@Apple.COM (David Lyons)
Newsgroups: comp.sys.apple
Subject: Re: Interrupts
Message-ID: <32886@apple.Apple.COM>
Date: 6 Jul 89 01:06:13 GMT
References: <8907050216.AA10350@crash.cts.com>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 28

In article <8907050216.AA10350@crash.cts.com> pnet01!pro-simasd!pro-nsfmat!pro-ldm!aaron.p@nosc.mil writes:
>
>   Could anyone supply me with information regarding interrupts?
> 
>in particular, I'd like to know how to preserve the Accumulator on returning
>from them. I've seen the address $45 LDA'ed many times in other peoples
>routines, but when I tried to put that in, it didn't work properly. I'm
>attempting to write my own drivers for my card, and I want them to be
>compatible with prodos, so I suppose the Prodos Interrupt info would also be
>helpful:  I've noticed that there is an interrupt vector available in prodos,
>but I don't have any of the information necessary to Utilize it. 

ProDOS 8 provides the calls ALLOC_INTERRUPT and DEALLOC_INTERRUPT.  Use them.
Look them up in the ProDOS 8 Technical Reference Manual or any decent third-
party reference on ProDOS 8.  ProDOS takes care of preserving A for you.

If you aren't using ProDOS's interrupt facilities, life becomes much more
ugly, and you have to take various possible machine configurations into
consideration.

 --Dave Lyons, Apple Computer, Inc.          |   DAL Systems
   AppleLink--Apple Edition: DAVE.LYONS      |   P.O. Box 875
   AppleLink--Personal Edition: Dave Lyons   |   Cupertino, CA 95015-0875
   GEnie: D.LYONS2 or DAVE.LYONS         CompuServe: 72177,3233
   Internet/BITNET:  dlyons@apple.com    UUCP:  ...!ames!apple!dlyons

   My opinions are my own, not Apple's.