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Re: rtVAX300 .. need help..

On 2013-01-10 23:04, Paul Koning wrote:

On Jan 10, 2013, at 4:33 PM, 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).

PDP-11 CPU internal registers appear in I/O address space, with some 
exceptions: the general registers are not visible there except in the 11/10.  
(They have listed addresses, but those only work from the console, not from 
programs, with that one exception.)  And yes, on the PDP-10, the general 
registers live at memory addresses 0 to 017.

It's more than the 11/10, but it's also really weird, and I don't remember if it's front panel only, but you might be right on that one.


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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