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Re: rtVAX300 .. need help..

> I think I have really simple and near stupid questions about the
> architecture that may be is realized on that shitty ISA Board with
> the CVAX on it.  Nobody tries to even recognize those questions.

Actually not true.  I do recognize the questions.  They're reasonable
questions.  I've just kept silent because I have no answers for them.

> Again: What exactly are that MISC CPU internal registers?

I don't know.

> Are those [...]?

I don't know.

> [...], so I'm short on time.

This is a common complaint in this hobby.  I have 74 items on my "when
I have the time" to-do list.  Most of them are not classiccmp things,
but some are....

> Next thing is, I'm not an natural english speaker, sometimes I have
> problems to recognize how that's meant what one writes, sometimes I
> have problems to express myself.

Your English is much, much better than my German.  It's true that
misunderstandings can arise, but, for the most part, I don't think this
is where the problem is.  My impression is that you have questions,
perfectly reasonable questions, and are having trouble because you
aren't getting answers.  But you probably aren't getting answers
because nobody on the list _has_ the answers.  It's possible (albeit
not especially likely in this case) that nobody now living has the

> I was never in UK, never in the US and my english is coming entirely
> from reading/writing Mails with people like you and from working on
> Unix machines.

I am very impressed.  I do not think my German would be as good in the
analogous case.

> I got the first signs of life from that rtVAX in a relative short
> time with the help from Mouse und yours, but with that little effort
> that I could make the last days, the project "porting NetBSD to an
> rtVAX300 board" will take for ever..

You have set yourself a relatively difficult task.  You have made
progress faster than I would expect from someone who started out not
even knowing any VAX machine - nor even assembly - language.  But it is
still a difficult task.

> In short: If I ask if there is an dedicated Interrupt controller in
> the other VAXen or if it is normal that CPU REGs are mapped to
> Address Space, then it isn't much help to read that none of the
> machines are water cooled.

True.  Part of this may be that nobody knows the answers.  Part of it
is probably the same topic drift that always happens on mailing lists.

I don't know the answers.  On the VAXen I know, there are some devices
(the timer facility built around the NICR and ICCS IPRs, the console
SLU on machines that use MTPR/MFPR console access, etc) that don't
really have anything I could call an interrupt controller - or, to put
it another way, the interrupt controller is built into the VAX IPL
arbitration logic.  For other devices (Unibus, Qbus, etc), there is
hardware for this; for example, how Qbus interrupts turn into VAX SCB
vectors and processor priority levels is specific to the Qbus
implementation in question.  I don't know how your rtVAX 300 does
interrupt arbitration and mapping.  That information might be buried
somewhere in the ROM code, in which case it might mean a lot of
searching through the code to find it.  Or it might not, if the ROM
code doesn't use interrupts.

I have trouble thinking where else you might find it, short of a lucky
coincidence such as meeting, by chance, someone who happened to design
the hardware in question.

I fear this is not very helpful.  But you do appear to be breaking
relatively new ground here, so, unless and until someone appears with
the relevant hardware documentation from back when DEC made that
hardware (or other information, such as someone who used to work with
it), I don't have much to offer.  Not because I don't want to help, but
because I have no help to give.

I may someday have the time to go through the ROM code in enough detail
to figure that out.  But I don't have that kind of time right now any
more than you do.

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