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data sheet / circuit diagram for Sun SCSI controllers.

Discussion in 'Sun Hardware' started by Dave (from the UK), Jan 29, 2006.

  1. Does anyone have any circuit diagrams (board layout even) for the Sun
    375-0005 (SE dual SCSI card) and the 375-0006 (HVD dual SCSI card)? Or
    data sheet on the LSI 53C876 chip?

    I need both HVD and SE SCSI controllers, but don't want to use two PCI
    slots.

    I am considering of perhaps getting two of these boards (I have a SE
    one), swapping some chips, and so making a hybrid board, that has one SE
    and one HVD channel on the same board.

    Sound possible?

    Without looking too closely, U3, U4 and U5 probably drives channel A and
    U6, U7 and U8 probably drives channel B.

    Or perhaps the PCBs are different. But I doubt that. Anyone with any
    more detailed information ????

    Anyone has a data sheet for the LSI 53C876 chip? I looked on the LSI web
    site, but can't find it. But I suspect it can be found. I see a
    reference to someone in a Sun forum looking at the data sheet. My guess
    is the data sheet will show what external chips are needed to drive SE
    and HVD.

    --
    Dave K

    http://www.southminster-branch-line.org.uk/

    Please note my email address changes periodically to avoid spam.
    It is always of the form: [email protected] Hitting reply will work
    for a couple of months only. Later set it manually. The month is
    always written in 3 letters (e.g. Jan, not January etc)
     
    Dave (from the UK), Jan 29, 2006
    #1
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  2. Dave (from the UK)

    Daniel Rock Guest

    Daniel Rock, Jan 29, 2006
    #2
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  3. Thanks. Obviously I have not read it carefully, but it says it has a
    single ended (SE) interface. Searching with acroread for the word HVD in
    that data sheet, I find it does not exist.

    I am now wondering if the chip needs extra chips to drive HVD that it
    does not need to drive SE? In other words, you need a SE -> HVD chip
    somewhere. That might make conversion quite difficult, as quite a few
    changes would probably be needed to the board. But if possible, one
    would probably start with an HVD board and remove the driver on one
    channel only.

    I don't suppose anyone is aware of a SCSI board being made like this -
    i.e. both HVD and SE on the same board? If someone else makes one, but
    it uses that chip, there is no real reason it would not work in a Sun.
    I'm not bothered about whether it will boot or not.

    --
    Dave K

    http://www.southminster-branch-line.org.uk/

    Please note my email address changes periodically to avoid spam.
    It is always of the form: [email protected] Hitting reply will work
    for a couple of months only. Later set it manually. The month is
    always written in 3 letters (e.g. Jan, not January etc)
     
    Dave (from the UK), Jan 29, 2006
    #3
  4. Dave (from the UK)

    Daniel Rock Guest

    What about Section 2.2.7.1 and Figure 2.5 (on page 2-27 (49))?
     
    Daniel Rock, Jan 30, 2006
    #4
  5. Thanks, as you say, that shows the wiring for differential - they don't
    seem to refer to it as HVD, but I think that is what they mean.

    Take a look at these two cards:

    The SYM22810 (which looks identical to the Sun 375-0005 single ended board)
    http://www.lsilogic.com/products/scsi_hbas/lsi22801.html

    and the SYM22802 (which I assume is the same as the Sun 375-0006 HVD
    board, although I can't verify this - can anyone??)
    http://www.lsilogic.com/products/scsi_hbas/lsi22802.html

    The board layouts are *very* different.

    So whilst looking at the data sheet it would appear you can have the
    chip drive one channel single-ended and the other channel differential,
    actually hacking one of those Sun SCSI boards to do the same would be a
    nightmare.

    I was rather hoping that the changes would be minimal, so only requiring
    changing a few chips over, but that does not look like it will be possible.

    I know SCSI converters are made.

    Ideally I'd like to get the SE tape drive on one of the two existing
    Ultra Wide SE SCSI buses in the Ultra 80. It seems crazy the box has two
    SE SCSI channels, but no way of getting the signals to an internal tape
    drive. At least if this is possible, nobody has replied to my earlier
    post telling me how to do it.

    Yet I think a tape drive was an option for the Ultra 80 - perhaps it
    needed a SCSI controller installed too. Does anyone know?

    --
    Dave K

    http://www.southminster-branch-line.org.uk/

    Please note my email address changes periodically to avoid spam.
    It is always of the form: [email protected] Hitting reply will work
    for a couple of months only. Later set it manually. The month is
    always written in 3 letters (e.g. Jan, not January etc)
     
    Dave (from the UK), Jan 30, 2006
    #5
  6. Dave (from the UK)

    * Me * Guest

    Dave,

    I have a 375-0006 and a 375-0005 sitting on my shelf. Is there anything
    particular that you would like to know from them?

    A quick look at the boards shows the same SYMBios chip part number ... with
    the difference appearing to be the drive chips (transistors) interface to
    the SCSI connections.

    Let me know if there any anything you require and I will see what I can do
    to help. Note that I will be away from email for a couple of days.

    Cheers
     
    * Me *, Jan 30, 2006
    #6

  7. I'm interested basically in how similar the boards look. If the layout
    is very similar between the two boards, then it may be possible to lift
    some chips off of the HVD board, lift some chips off of the SE board and
    move them across.

    It would need to be the chips that connect to the SCSI connectors. But
    if the Sun boards are like

    http://www.lsilogic.com/products/scsi_hbas/lsi22801.html
    http://www.lsilogic.com/products/scsi_hbas/lsi22802.html

    then it looks impractical. They are too dissimilar.

    Perhaps tomorrow I'll shut my U80 down and look inside to see if it is
    practical to connect a SE tape drive to one of the two SE controllers
    that are already on the U80's motherboard.

    A DDS-3 tape drive was available as an internal option, and the machine
    has spare for a floppy as well as two internal 5.25" drives, so I assume
    you can fit floppy+CD+tape. But I can't see how - at least from memory,
    the connectors will not allow it.
    --
    Dave K

    http://www.southminster-branch-line.org.uk/

    Please note my email address changes periodically to avoid spam.
    It is always of the form: [email protected] Hitting reply will work
    for a couple of months only. Later set it manually. The month is
    always written in 3 letters (e.g. Jan, not January etc)
     
    Dave (from the UK), Jan 30, 2006
    #7
  8. Dave (from the UK)

    * Me * Guest

    Dave,

    Those pictures are pretty accurate to what I have on my shelf (spare parts
    box sitting on my shelf).

    The SYMBios chips are the same ... then the rest is quite a bit different -
    as you correctly surmized.

    I am surprised that you require HVD. That is the reason that the board in
    my spare parts box - no real requirement for connecting anything SCSI that
    is high voltage differential. (not to mention those connecting cables for
    the external ports are quite expensive - the high density sockets).

    Another option is to bring out one of the internal SE connectors to the back
    of your case. Many PC computer stores (at least here) have stock of 68 pin
    internal to 68 pin external (card slot bracket) connector. Would this be an
    option for you? (I picked one up for $6.00 at a shop that recycles old
    computers).

    Cheers
    Glenn
     
    * Me *, Jan 30, 2006
    #8
  9. OK. That means a simple hack to get a dual card, that handles both SE
    and HVD is not feasible.
    I have a Sun StorEDGE L9 tape autoloader (takes about eight or nine
    40/80 GB tapes). That needs HVD, so I have an HVD card. The card is
    actually made by IBM, but has a 53C875 (single channel) chip. Works fine
    and at the time I bought it (many years ago) is was a lot cheaper than a
    Sun SCSI card. Now, they are all next to nothing.

    I'm a bit reluctant to use the autoloader much, since if it goes wrong,
    I don't have another DLT drive. But I guess a single DLT drive is not
    that expensive. I don't need the autoloader.

    With DDS-4, I have several options for retrieving the data. A friend has
    a DDS-4 drive and my previous employer would not mind me using theirs to
    get data off of a tape. With DLT I have less options.
    That is already done. But how to I connect the internal tape drive to
    it? I'd like to use an *internal* DDS-4 tape drive. I do have an
    external DDS-4 drive, but I'd rather make that portable and not tie it
    to the Ultra 80 all the time.

    I should be able to get a DDS-4 drive for about £40 (~ $70 when
    converted to USD), so they are not that expensive.

    I think the SCSI connection issues are not such a problem after all. If
    this thread

    http://groups.google.co.uk/group/co...e?lnk=st&q=dds4&rnum=1&hl=en#8a344ceff3c244ee

    is to be believed then the data transfer rate of a DDS4 drive is not
    sufficient to overload an 8-bit narrow bus.

    So perhaps putting a 50->68 pin adapter on the rear of the tape drive
    will do. Then the cable that feeds the CD-ROM drive will feed the tape
    too. I'm not sure if the cable has another 50-pin connector on it, but
    if not one could easily be crimped on.

    I just checked the installation manual (802-7791) for the DDS-3 tape
    drive from Sun:

    http://sunsolve.sun.com/data/802/802-7791/pdf/001.dds3.pdf

    That shows the DDS-3 using a 50-pin connector on the rear. But DDS-4
    drives are faster than DDS-3, so I'm still not 100% convinced using only
    a narrow bus is a good idea. It might be if its the only thing on the
    bus, but if you are backing up from a disk on that bus too, I am not so
    sure.

    For many things slowing the bus down a bit results only in a loss of
    performance, but on tape drives it causes them to constantly have to
    stop & start, which I believe does not do them a lot of good and results
    in a dramatic loss of speed.

    --
    Dave K

    http://www.southminster-branch-line.org.uk/

    Please note my email address changes periodically to avoid spam.
    It is always of the form: [email protected] Hitting reply will work
    for a couple of months only. Later set it manually. The month is
    always written in 3 letters (e.g. Jan, not January etc)
     
    Dave (from the UK), Jan 30, 2006
    #9
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