Path: utzoo!utgpu!water!watmath!clyde!att-cb!osu-cis!tut.cis.ohio-state.edu!mailrus!caen.engin.umich.edu!mystone
From: mystone@caen.engin.umich.edu (Dean Yu)
Newsgroups: comp.sys.mac.programmer
Subject: Re: screen memory address
Summary: ScrnBase
Keywords: mac video addressing
Message-ID: <805@blue.engin.umich.edu>
Date: 17 Apr 88 15:49:00 GMT
References: <4396@ihlpf.ATT.COM>
Organization: caen
Lines: 16

In article <4396@ihlpf.ATT.COM>, dennis@ihlpf.ATT.COM (Dennis Dale) writes:
> 
> Is there a memory location or system call that I can use to find out
> the address of the start of the memory mapped video RAM?  I'd like
> to do some things by directly 'poking' them to RAM, which is easy
> enough to do, but if I hard code the start address, it won't work on
> machines of different sizes.

  The global variable ScrnBase holds the address of the start of the main
screen buffer.  See IM II page 19 for details.

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Dean Yu                             |
mystone@caen.engin.umich.edu        |  This space intentionally left blank
I'm too young to have an opinion    | 
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