Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!uunet!zephyr.ens.tek.com!tektronix!reed!chaffee
From: chaffee@reed.UUCP (Alex Chaffee)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Animation
Message-ID: <16178@reed.UUCP>
Date: 2 Mar 91 03:08:58 GMT
References: <12151@goofy.Apple.COM> <16145@reed.UUCP> <91058.111052CXT105@psuvm.psu.edu>
Reply-To: chaffee@reed.UUCP (Alex Chaffee)
Organization: Reed College, Portland OR
Lines: 25

In <91058.111052CXT105@psuvm.psu.edu> CXT105@psuvm.psu.edu (Christopher Tate) writes:

>[Alex Chaffee talks about using VBL tasks to get true vertical retrace sync
> on Mac II-series machines, instead of watching the tick count.]

>The only problem is that not all Macs have slots.  For those that don't,
>the best you can do is to watch the tick count by one of those methods
>already debated here.

Is that true? I was under the impression that on slotless Macs, SlotVInstall
et al. just mimiced VInstall (et al.). Assuming a recent enough version of
system software. If that is so, then the techniques I described (and provide
source for in a concurrent post) should work exactly like TickCount.

Of course, if I'm wrong, you're right. :-) I guess the best thing to do is
look to see if SlotVInstall is an implemented trap before braching to the
slot-using code.

 - Alex

-- 
Alex Chaffee
chaffee@reed.{UUCP,BITNET}
Reed College, Portland OR 97202
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