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From: gillies@p.cs.uiuc.edu
Newsgroups: comp.sys.mac.programmer
Subject: Video DRAM usage?
Message-ID: <104700059@p.cs.uiuc.edu>
Date: 15 Aug 89 18:07:00 GMT
Lines: 15
Nf-ID: #N:p.cs.uiuc.edu:104700059:000:652
Nf-From: p.cs.uiuc.edu!gillies    Aug 15 13:07:00 1989


My calculations show that 217088 bytes of memory are unused by the Mac
II video card.  That is, assuming that an 8-bit video card requires
512K of dual-ported DRAM, and the display only uses 640*480 = 307200
bytes of memory (108544 unused bytes on a 4-bit card).

Does Color QuickDraw use this memory for something useful?  Has anyone
written code to exploit this extra memory?  It seems like an ideal
place to put a disk cache, or temporary pixel maps.  I was just
wondering.


Don Gillies, Dept. of Computer Science, University of Illinois
1304 W. Springfield, Urbana, Ill 61801      
ARPA: gillies@cs.uiuc.edu   UUCP: {uunet,harvard}!uiucdcs!gillies