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Re: rtVAX300 .. need help..



On 2013-01-10 22:33, Rhialto wrote:
On Thu 10 Jan 2013 at 04:29:36 +0100, Johnny Billquist wrote:
Just a few short comments. The VAX internal registers are not memory
mapped, ever. That would be against the architecture specification.

Well, the thought isn't that strange. Iirc, the PDP-11 has its CPU
registers mapped (somewhere in high memory?) and the PDP-10 too (at
address 0, iirc).

Oh, yeah. And the PDP-10 don't really have registers as much as just that one operator to instructions only have four bits, so the memory locations possible to express are a bit limited. :-)
And they are called "accumulators"... ;-)

        Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol


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