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From: heath@ncrcae.Columbia.NCR.COM (Robert Heath)
Newsgroups: comp.sys.m88k
Subject: Baseline 88K Mask under BCS
Keywords: 88K mask BCS
Message-ID: <5395@ncrcae.Columbia.NCR.COM>
Date: 21 Nov 89 19:13:30 GMT
Reply-To: heath@ncrcae.Columbia.NCR.COM (Robert Heath)
Organization: NCR Corp., Engineering & Manufacturing - Columbia, SC
Lines: 26

In the last year or so the 88100 CPU has gone through a number of versions
(e.g. D.0, D.5, E.0, E.1, E.2, etc.).  To compensate for known chip problems,
one of the steps in the compilation process has been a "silicon filter"
which inserts instructions into the compiler's output before going
to the assembler. These instructions are essentially software workarounds.  
The silicon filter provides reliability at some cost to performance.

As later versions of the chip emerge, bugs are corrected, and the need 
for silicon filtering diminishes.
Eventually no silicon filtering will be required as long as one runs with
the "bug free" chip.   This suggests that software generated for a later
mask will not reliably run on an earlier mask.

From a shrink-wrapped software developer's point of view, one wants minimal 
filtering at maximum reliability.  To third party developers, that means 
targeting their 88K binaries to some baseline version of the mask.
My question is: what version of the 88100 silicon do software vendors
consider the baseline ? (e.g. D.5, E.2, etc.)

Since this is more of a business decision, you won't find the answer in
your 88open BCS and OCS standards.

	Robert Heath
	NCR Corp.
	W.Columbia, SC
	803-791-6315