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From: chu@acsu.buffalo.edu (john c chu)
Newsgroups: comp.sys.atari.st.tech
Subject: Vertical Blank routines
Message-ID: <79358@eerie.acsu.Buffalo.EDU>
Date: 8 Jun 91 12:22:17 GMT
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Can someone mail me the dos and don'ts of using routines that run
every vertical blank? If the Abacus ST Internals is accurate in this
case, I think I know how to install a routine. However, I'd like to
know if it is ok to call an XBIOS routine during that time, what the
maximum length a routine should be and so on...

(also, is it correct to add your routine to the VBL queue by altering
the system variables? Their locations do not (and will not) change
between versions of TOS?)

thanks...

					john
				chu@acsu.buffalo.edu