Re: Modern disk system for our -11s - DEC

This is a discussion on Re: Modern disk system for our -11s - DEC ; Pete Turnbull wrote in message news: ... > Martin Bishop wrote: > > ... > > A much smarter solution would be to spend 100 or perhaps a little more > on a QBus SCSI card to replace the RQDX3. ...

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Thread: Re: Modern disk system for our -11s

  1. Re: Modern disk system for our -11s

    Pete Turnbull wrote in message news:...
    > Martin Bishop wrote:
    >
    > ...
    >
    > A much smarter solution would be to spend 100 or perhaps a little more
    > on a QBus SCSI card to replace the RQDX3. Everything that talks to an
    > RQDX3 uses the MSCP protocol, as do all the common QBus SCSI controllers.


    You've clearly not tried to buy one lately. 100 pounds, or 100 of any
    currency except perhaps for gold bars, will leave you empty handed.
    I've been trying to locate one for years with a larger budget than
    that.

    As a DEC hobbyist/collector I've been following threads like this one
    for a while*, and with several machines that would benefit, like
    others I am highly motivated to either assist in, or take advantage of
    the results of, any such project.

    I favour the MSCP emulation approach. I have the MSCP Basic Disk
    Functions Manual (v1.2), "part of the UDA50 Programmer's Doc. Kit, 1st
    ed., April 1992". Can anyone provide the rest of this kit, or any
    further detailed information that might be of help in designing an
    MSCP controller for QBus and Unibus? What about scanned versions of
    bus specs and design documents?

    --Toby

    * Such as:
    http://mail-index.netbsd.org/port-va...1/03/0015.html
    http://groups.google.com/groups?thre...ing.google.com

  2. Re: Modern disk system for our -11s

    Toby Thain wrote:
    > I favour the MSCP emulation approach.


    One significant advantage is that disk size is found
    using MSCP via querying the device, which allows a
    variety of actual (e.g. SCSI, which also has a size
    query) disks to be used. Since PDP-11s rarely had
    disks over a gigabyte, there is a *huge* supply of
    used (SCSI) disks available very cheaply that are
    as large as one could actually employ (due to OS or
    filesystem structure limitations).

    I don't see any need to involve a whole PC in the
    disk subsystem. There is about as much work needed
    to interface e.g. MSCP Qbus to a PCI interface with
    software to get at the PC's disk as there is to
    interface MSCP to SCSI directly. As somebody else
    observed, a C implementation of MSCP already exists
    in SIMH, and I'm sure there are C implementations
    of drivers for various common SCSI chips (probably
    in Linux, certainly in Plan 9). Therefore the
    hardware boils down to a Qbus (or Unibus) board with
    the necessary interface and control logic, a SCSI
    chip with a bit of support logic, paths between the
    two, and a small microprocessor with its RAM and ROM
    to act as central control. If my employer cared
    about such things, I could develop one and run off
    a modest quantity of boards; my *guess* is that it
    would run about $400 apiece (populated). However,
    I'm sure that any time I spent on this would work
    against me with regard to my employer.

  3. Re: Modern disk system for our -11s

    Douglas A. Gwyn wrote:

    > Toby Thain wrote:
    >> I favour the MSCP emulation approach.

    >
    > One significant advantage is that disk size is found
    > using MSCP via querying the device, which allows a
    > variety of actual (e.g. SCSI, which also has a size
    > query) disks to be used. Since PDP-11s rarely had
    > disks over a gigabyte, there is a *huge* supply of
    > used (SCSI) disks available very cheaply that are
    > as large as one could actually employ (due to OS or
    > filesystem structure limitations).
    >
    > I don't see any need to involve a whole PC in the
    > disk subsystem. There is about as much work needed
    > to interface e.g. MSCP Qbus to a PCI interface with
    > software to get at the PC's disk as there is to
    > interface MSCP to SCSI directly. As somebody else
    > observed, a C implementation of MSCP already exists
    > in SIMH, and I'm sure there are C implementations
    > of drivers for various common SCSI chips (probably
    > in Linux, certainly in Plan 9). Therefore the
    > hardware boils down to a Qbus (or Unibus) board with
    > the necessary interface and control logic, a SCSI
    > chip with a bit of support logic, paths between the
    > two, and a small microprocessor with its RAM and ROM
    > to act as central control. If my employer cared
    > about such things, I could develop one and run off
    > a modest quantity of boards; my *guess* is that it
    > would run about $400 apiece (populated). However,
    > I'm sure that any time I spent on this would work
    > against me with regard to my employer.


    I am running such a project, <http://www.geocities.com/mscpscsi

  4. Re: Modern disk system for our -11s - help wanted

    "Douglas A. Gwyn" wrote in message news:...
    > Toby Thain wrote:
    > > I favour the MSCP emulation approach.

    >
    > ...
    > hardware boils down to a Qbus (or Unibus) board with
    > the necessary interface and control logic, a SCSI
    > chip with a bit of support logic, paths between the
    > two, and a small microprocessor with its RAM and ROM
    > to act as central control.


    Together with a hardware expert I am actively researching this
    direction, with IDE as the disk interface. (This project evolved
    independently from Mr Russell's initiative.)

    We are currently looking for a QBus or Unibus machine for hardware
    testing, if anyone can assist with a working MicroVAX or MicroPDP or
    better for pickup within reasonable (1 day) driving distance from
    Toronto, please contact me.

    Relevant documentation (bus, architecture) also sought.

    --Toby

  5. Re: Modern disk system for our -11s - help wanted

    In article ,
    toby@telegraphics.com.au (Toby Thain) writes:
    > "Douglas A. Gwyn" wrote in message news:...
    >> Toby Thain wrote:
    >> > I favour the MSCP emulation approach.

    >>
    >> ...
    >> hardware boils down to a Qbus (or Unibus) board with
    >> the necessary interface and control logic, a SCSI
    >> chip with a bit of support logic, paths between the
    >> two, and a small microprocessor with its RAM and ROM
    >> to act as central control.

    >
    > Together with a hardware expert I am actively researching this
    > direction, with IDE as the disk interface. (This project evolved
    > independently from Mr Russell's initiative.)
    >
    > We are currently looking for a QBus or Unibus machine for hardware
    > testing, if anyone can assist with a working MicroVAX or MicroPDP or
    > better for pickup within reasonable (1 day) driving distance from
    > Toronto, please contact me.


    I guess it depends on how fast you drive, but I could probably loan you a
    MicroVAX for QBUS and an 11/44 for UNIBUS (mind you, there is no such thing
    as a Micro-UNIBUS! :-) Just south of Scranton, PA. (These are both at
    my home, not here at the University.)

    >
    > Relevant documentation (bus, architecture) also sought.


    Not sure what I have that you could use, but you would be free to look
    in my collection and borrow anything that would help. I'm going to be
    away from the ned of October until next Spring so I won't be using any
    of this stuff in the near future.

    bill

    --
    Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
    bill@cs.scranton.edu | and a sheep voting on what's for dinner.
    University of Scranton |
    Scranton, Pennsylvania | #include

  6. Re: Modern disk system for our -11s

    In alt.sys.pdp11 Toby Thain wrote:
    > Pete Turnbull wrote in message news:...
    >> Martin Bishop wrote:
    >>
    >> ...
    >>
    >> A much smarter solution would be to spend 100 or perhaps a little more
    >> on a QBus SCSI card to replace the RQDX3. Everything that talks to an
    >> RQDX3 uses the MSCP protocol, as do all the common QBus SCSI controllers.


    > You've clearly not tried to buy one lately. 100 pounds, or 100 of any
    > currency except perhaps for gold bars, will leave you empty handed.
    > I've been trying to locate one for years with a larger budget than
    > that.


    Well, I've seen them go in the last year (sometimes inside machines, which
    tends to make them cheaper, believe it or not) for less than I've seen an
    RD54 fetch. You're right, though, 100 is a bit of an underestimate these
    days.

    > I favour the MSCP emulation approach. I have the MSCP Basic Disk
    > Functions Manual (v1.2), "part of the UDA50 Programmer's Doc. Kit, 1st
    > ed., April 1992". Can anyone provide the rest of this kit


    I scanned it a while ago, and Al Kossow has it on bitsavers:

    http://bitsavers.org/pdf/dec/disc/UDA50/

    --
    Pete Peter Turnbull
    Network Manager
    University of York

  7. Re: Modern disk system for our -11s

    toby@telegraphics.com.au (Toby Thain) writes:

    > I favour the MSCP emulation approach. I have the MSCP Basic Disk
    > Functions Manual (v1.2), "part of the UDA50 Programmer's Doc. Kit, 1st
    > ed., April 1992". Can anyone provide the rest of this kit, or any

    ^^^^ 1982 I think
    > further detailed information that might be of help in designing an
    > MSCP controller for QBus and Unibus? What about scanned versions of
    > bus specs and design documents?


    Alan Frisby has copies I think. Mine is in a huge pile of stuff waiting
    to be scanned. The other docs where the UDA-50 port manual, and the RA-80,
    81 and RA-60 service pocket guides.

    All the stuff on shadow assist function and encryption keying was kept
    out of the public docs, and in fact the UDA-50 doc kit was pulled very
    quickly.

    --
    Paul Repacholi 1 Crescent Rd.,
    +61 (08) 9257-1001 Kalamunda.
    West Australia 6076
    comp.os.vms,- The Older, Grumpier Slashdot
    Raw, Cooked or Well-done, it's all half baked.
    EPIC, The Architecture of the future, always has been, always will be.

  8. Re: Modern disk system for our -11s - help wanted

    toby@telegraphics.com.au (Toby Thain) wrote in message news:...
    > "Douglas A. Gwyn" wrote in message news:...
    > > Toby Thain wrote:
    > > > I favour the MSCP emulation approach.

    > >
    > > ...
    > > hardware boils down to a Qbus (or Unibus) board with
    > > the necessary interface and control logic, a SCSI
    > > chip with a bit of support logic, paths between the
    > > two, and a small microprocessor with its RAM and ROM
    > > to act as central control.

    >
    > Together with a hardware expert I am actively researching this
    > direction, with IDE as the disk interface. (This project evolved
    > independently from Mr Russell's initiative.)


    If you haven't done so already, you might like to look at
    http://www.chd.dyndns.org/qbus_ide I'm not sure how much work would be
    required to complete his project. There are enough old IDE disks
    around to last all our lifetimes, and not suffering from Microbloat,
    even a 20Mb disk is big for PDP operating systems.

    Chris

  9. Re: Modern disk system for our -11s - help wanted

    On 30 Sep 2004 08:06:45 -0700 in alt.sys.pdp11,
    toby@telegraphics.com.au (Toby Thain) wrote:

    >We are currently looking for a QBus or Unibus machine for hardware
    >testing, if anyone can assist with a working MicroVAX or MicroPDP or
    >better for pickup within reasonable (1 day) driving distance from
    >Toronto, please contact me.


    Toronto @.au? Is that Toronto, Lake Macquarie, New South Wales,
    Australia or Toronto, Ontario, Canada?

    --
    Thanks. Take care, Brian Inglis Calgary, Alberta, Canada

    Brian.Inglis@CSi.com (Brian[dot]Inglis{at}SystematicSW[dot]ab[dot]ca)
    fake address use address above to reply

  10. Re: Modern disk system for our -11s - help wanted

    In article <29ppl0111pu0fbeie6tt6bdh434cehdcgn@4ax.com>,
    Brian Inglis writes:
    > On 30 Sep 2004 08:06:45 -0700 in alt.sys.pdp11,
    > toby@telegraphics.com.au (Toby Thain) wrote:
    >
    >>We are currently looking for a QBus or Unibus machine for hardware
    >>testing, if anyone can assist with a working MicroVAX or MicroPDP or
    >>better for pickup within reasonable (1 day) driving distance from
    >>Toronto, please contact me.

    >
    > Toronto @.au? Is that Toronto, Lake Macquarie, New South Wales,
    > Australia or Toronto, Ontario, Canada?
    >


    I hadn't noticed that either. Maybe that's why I didn't get a response
    to my email. But, just in case, I'll post it here too.

    If that is the Toronto in Canada and you consider this "a days drive",
    then I can probably loan you a MicroVAX for QBUS and an 11/44 for UNIBUS,
    realizing that there is no such thing as a "Micro" UNIBUS. Of course,
    these would need to be picked up before the end of October as from then
    until April I will be away from home. I am located just south of Scranton,
    PA on I81. (about 20 minutes, 15 outside rush hour.)

    bill

    --
    Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
    bill@cs.scranton.edu | and a sheep voting on what's for dinner.
    University of Scranton |
    Scranton, Pennsylvania | #include

  11. Re: Modern disk system for our -11s - help wanted

    Bill Gunshannon wrote:
    > If that is the Toronto in Canada ...


    What, you won't drive to Australia?

  12. Re: Modern disk system for our -11s - help wanted

    In article <242dnbT2ttAGDcDcRVn-rA@comcast.com>,
    "Douglas A. Gwyn" writes:
    > Bill Gunshannon wrote:
    >> If that is the Toronto in Canada ...

    >
    > What, you won't drive to Australia?


    It wasn't me offering to do the driving. And, on top of that, even I
    can't drive to OZ in one day. :-)

    bill

    --
    Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
    bill@cs.scranton.edu | and a sheep voting on what's for dinner.
    University of Scranton |
    Scranton, Pennsylvania | #include

  13. Re: Modern disk system for our -11s - help wanted

    On Fri, 01 Oct 2004 13:15:22 -0400 in alt.sys.pdp11, "Douglas A. Gwyn"
    wrote:

    >Bill Gunshannon wrote:
    >> If that is the Toronto in Canada ...

    >
    >What, you won't drive to Australia?


    It's whether Toby (or associates) can pick up from Scranton.

    --
    Thanks. Take care, Brian Inglis Calgary, Alberta, Canada

    Brian.Inglis@CSi.com (Brian[dot]Inglis{at}SystematicSW[dot]ab[dot]ca)
    fake address use address above to reply

  14. Re: Modern disk system for our -11s - help wanted

    bill@cs.uofs.edu (Bill Gunshannon) wrote in message news:<2s52orF1glsl7U1@uni-berlin.de>...
    > In article <29ppl0111pu0fbeie6tt6bdh434cehdcgn@4ax.com>,
    > Brian Inglis writes:
    > > ...
    > > Toronto @.au? Is that Toronto, Lake Macquarie, New South Wales,
    > > Australia or Toronto, Ontario, Canada?


    Canada.

    > I hadn't noticed that either. Maybe that's why I didn't get a response
    > to my email. But, just in case, I'll post it here too.
    >
    > If that is the Toronto in Canada and you consider this "a days drive",
    > then I can probably loan you a MicroVAX for QBUS and an 11/44 for UNIBUS,
    > realizing that there is no such thing as a "Micro" UNIBUS. Of course,
    > these would need to be picked up before the end of October as from then
    > until April I will be away from home. I am located just south of Scranton,
    > PA on I81. (about 20 minutes, 15 outside rush hour.)


    Bill,

    I am sure I did see your e-mail but now I can't find it.
    Thanks for the info above, I'll contact you by e-mail.

    --Toby

    >
    > bill


  15. Re: Modern disk system for our -11s - help wanted

    Bill Gunshannon wrote:
    > And, on top of that, even I
    > can't drive to OZ in one day. :-)


    Just hop a tornado..

  16. Re: Modern disk system for our -11s - help wanted

    bill@cs.uofs.edu (Bill Gunshannon) writes:

    > It wasn't me offering to do the driving. And, on top of that, even
    > I can't drive to OZ in one day. :-)


    Not a problem, leave Perth at 10:30am Wed, arrive in LA at 18:45 Wed...

    --
    Paul Repacholi 1 Crescent Rd.,
    +61 (08) 9257-1001 Kalamunda.
    West Australia 6076
    comp.os.vms,- The Older, Grumpier Slashdot
    Raw, Cooked or Well-done, it's all half baked.
    EPIC, The Architecture of the future, always has been, always will be.

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