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Re: rtVAX300 .. need help..

As I mentioned, I have a static-zapped CVAX from the prototype run
of the rtVAX 300 hanging in my cubicle at work. Here are the numbers
stamped on the thing:

DEC 580B
(C) (R) DEC 1988
B434-72 A 8923

Which checks out as being a CVAX capable of a 60 ns cycle time.

On Mon, 7 Jan 2013, Holm Tiffe wrote:
What the heck is thisr:

#define KA49_SCSIMAP    0x27000000 /* KA49 SCSI SGMAP */

Just like it says, that would be the scatter/gather map for the
SCSI interface.

A scatter/gather map is like an MMU for a DMA device; it allows
the DMA device to map between addresses convenient to it and
physical addresses. I've forgotten everything I used to know
about the 53C94, so I don't remember how DMA works.
roger ivie

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