RD54 on RQDX3 identifies as an RX33

Lee Gleason

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Dec 2, 2012, 12:00:54 AM12/2/12

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Trying to add an RD54 to an 11/73 using an RQDX3 controller.

I've managed to get XXDP onto an RX50 floppy and boot it. When I run
ZRQCH0 from it to try and format the RD54, the program identifies the RD54
as an RX33. Anyone ever seen this behavior? Any troubleshooting
suggestions?

--
Lee K. Gleason N5ZMR
Control-G Consultants
lee.g...@comcast.net

Johnny Billquist

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Dec 2, 2012, 10:00:14 AM12/2/12

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On 2012-12-02 06:00, Lee Gleason wrote:
> Trying to add an RD54 to an 11/73 using an RQDX3 controller.
>
> I've managed to get XXDP onto an RX50 floppy and boot it. When I run
> ZRQCH0 from it to try and format the RD54, the program identifies the
> RD54 as an RX33. Anyone ever seen this behavior? Any troubleshooting
> suggestions?

Is it a genuine RD54? What version of ZRQCH0? Since the RD54 is pretty
"recent", I think there are versions of ZRQCH0 that don't know about it.
Also, maybe version of RQDX3 might matter.

Hmm, come to think of it, if ZRQCH0 isn't stupid, it should just report
the device name string as received over MSCP. Since the the RQDX
controllers, that name is pulled (I think) from the controller, the
version of the RQDX3 is what I would maybe look at first. Especially if
it is a genuine RD54.

Johnny

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

chrisj.doran%...@gtempaccount.com

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Dec 11, 2012, 3:53:59 AM12/11/12

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What does it say when you disconnect the RD54?

Silly question: You aren't by any chance using a PC-style cable with a twisted section in it, are you? All DEC systems I've met use straight cables.

What happens if you give other unit numbers?

Chris

glen herrmannsfeldt

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Dec 11, 2012, 4:31:38 AM12/11/12

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chrisj.doran%proemai...@gtempaccount.com wrote:

> What does it say when you disconnect the RD54?

> Silly question: You aren't by any chance using a PC-style cable
> with a twisted section in it, are you? All DEC systems I've
> met use straight cables.

The twist exchanges drive select lines and swaps a drive select
to a motor on line.

Pre-IBM PC the standard cable had four select lines and one
motor on line. The PC power supply couldn't power all the
drives at once, so they gave them separate lines.

> What happens if you give other unit numbers?

-- glen

lfe...@alumni.princeton.edu

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Jan 24, 2013, 9:06:16 PM1/24/13

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The revision notes in the diagnostic listing say that revision G fixed the problem of some RDxx drives being recognized as RX33. Are you sure that XXDP set has ZRQCH0, or does it have something older than ZRQCG? ?

Lou

Lee Gleason

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Jan 25, 2013, 12:10:49 PM1/25/13

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>The revision notes in the diagnostic listing say that revision G fixed the
>problem of some RDxx drives being recognized as RX33. Are you sure that

>XXDP set has ZRQCH0, or does it have something older ?>than ZRQCG? ?

>Lou

Thanks for the info. It's ZRQCH0. And as well, the MicroRSX installation
diskette also sees it as an RX33 (finally, a use for MicroRSX!) I'm starting
to suspect it's a problem with the unit select lines. I've gotten
sidetracked on the project, though - as support tools for getting this box
on the air, I was using my old PRO-380 and SIMH - now I've gotten interested
in playing with them and the 11/23 lays taken apart in the middle of the
floor - I've got to get back around to it again...

Johnny Billquist

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Jan 28, 2013, 8:10:30 AM1/28/13

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Still wondering about possible revisions on the RQDX3. But unit select
can also be it.
Or cable problems in general...

Johnny