[Simh] Error in DMC11/DMR11 Emulation in RSTS/E 10.1

[Paul Koning]

> On Jan 3, 2016, at 6:42 PM, Christian Gauger-Cosgrove <captainkirk359 at gmail.com> wrote:
> 
> On 3 January 2016 at 16:42, Paul Koning <paulkoning at comcast.net> wrote:
>> No, that's not what that means.
>> 
>> It does say that micro diagnostics are required; when those are disabled, the device is rejected because of that failure.
>> 
> Note that XM0 and XM1 provide the same "XMn: is missing ECO's, but
> will still function" as XM4; and XM4 has the micro-diagnostics
> DISABLED all three of those devices are TYPE=DMC and INIT accepted all
> three. The rejected devices are XM2 and XM3 which were defined as
> TYPE=DMR (one with and one without micro-diagnostics).

Ok, I misread it.  Will investigate why RSTS INIT doesn't like the current DMR emulation.

>> However, it also says that "XM0: is missing ECO's, but will still function."  That means the device is enabled, and it should be there and work when you start the system.  More precisely, if it doesn't work that would be for a different reason.
>> 
> I was assuming that the "XM0: is missing ECO's, but will still
> function." error meant that the specific DMC11 (since the DMR11
> doesn't work) would still function, even though the micro diagnostics
> aren't the latest revision. At least if I'm not misremembering aren't
> ECOs revisions to the device (hardware, microcode, or both)? (Or have
> I completely gotten confused.)

What's going on is that it reads the microcode ROM (or a portion of same) and compares it against an expected content.  If no match,  you get that message.

>> Tried what with QBus?  DMC?  Only a DMV is valid on Qbus.
>> 
> Yes, I tried to use the DMC with QBUS. Somehow, don't ask me how, but
> I got SIMH into a state where the DMC was enabled on a QBUS (11/93)
> machine... SIMH promptly crashed hard one made to start (told it to
> boot a device... and crash) as one should expect from abusing it like
> that. So that can be an ignored issue perhaps.

It ought to be rejected since it's not a valid configuration.

> Also, correct me if I'm wrong: There is no emulation of the DMV11,
> isn't there? Only QBUS DDCMP device I see is the DPV11 (which I'd like
> to point out: Doesn't work in RSTS/E as far as I've seen).

Correct, DPV won't work.  The only supported DDCMP devices are DMC, DMR, and DMP (all Unibus) and DMV (Qbus).  DMP and DMV are close relatives; they are similar to DMR but with the addition of multipoint support.  It doesn't look like they are emulated in SIMH.  Doing so for the point to point subset would probably not be all that hard; multipoint is a different matter entirely and probably not worth the trouble.

	paul