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From: Al Johnston <sofeise@mindspring.com>
Newsgroups: comp.lang.ada
Subject: gnat/ppc and a32 blt transfers
Date: Wed, 01 Nov 2000 14:47:35 -0500
Organization: MindSpring Enterprises
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Date: 2000-11-01T19:47:04+00:00
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We are running gnat/solaris->ppc.  our cpu cards are mvme2700 in a 64x
vme chassis.

I am having trouble with 64 bit accesses from the cpu to some of our
vme (slave) cards.  The slaves do not like the MBLT (AM=0c) accesses 
that the compilers code is causing to be used on the bus.

So what I need to do is write my own ":=" and relational operators
that access the 64bit entity via two 32 bit reads/writes.

I was wondering if this would be an appropriate place you use
ada95's "controlled types"?

If so, how much overhead does this involve.


thanks.

-al