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<p class=MsoNormal> It looks like _any_ MSCP emulation in simh on a
UNIBUS machine reports the controller type as a UDA50, and any QBUS simulation
reports the controller as a RQDX3. This is a rather simple approach that
leads to all kinds of funky and incorrect situations, especially on the
QBUS. For example, if you attach an RA drive to a QBUS -11 and boot
RSTS, then RSTS will tell you that the controller is a RQDX3 with, say, an RA81
drive. Clearly impossible… Likewise if you attempt to
use a RRD40 on a PDP-11 it’ll think the controller is a RQDX3 –
again, impossible. I’m more than a little surprised that RSTS doesn’t
crash, given how fussy RSTS is about the hardware, but it doesn’t seem to
care.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal> In any case it bugged me to see all these bogus
hardware configurations, so I’ve hacked up (er, “enhanced”)
the “set rq” command in simh so you can now say<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal> set
rq uda50<o:p></o:p></p>
<p class=MsoNormal> set
rq kda50<o:p></o:p></p>
<p class=MsoNormal> set
rq rqdx3<o:p></o:p></p>
<p class=MsoNormal> set
rq krq50<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>There’s no sanity checking so it’s still
possible to create impossible configurations, but at least now you can actually
create _possible_ configurations too.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal> Even this is still a pretty simply minded approach,
since other things (e.g. hardware revision level, firmware version, etc) should
also change when you change the controller type, but at least now when the
emulated OS shows the hardware configuration you get rational results.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal> Is this worth adding to the simh code base?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Bob Armstrong<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
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