• s (unregistered)

    Installing Linux... Answering questions... Suddenly, power goes down. The UPS has switched off. Seemingly, unrelated. Trying again... the UPS switches off again. Same point of installation. This time, a bit of thought, I unplug the UPS serial cable from the PC, try installing Linux again. We reach the point. "Detecting mice. Serial mouse: none."

  • YdK (unregistered) in reply to Simmo

    This story reminds me a little of a problem we had with our home PC about 10 years ago.

    At some point the pc would refuse to load internet sites, unless you wacked the mouse around like crazy. Turns out that somehow the internal modem (14k4 ofcourse...) had somehow went from com4 to com3 (or the other way around, can't remember) which put it on the same IRQ as the serial mouse (the real WTF etc... I know).

    Eventually we just disabled com3 in the BIOS, which solved the problem.

  • RogerWilco (unregistered) in reply to Kemp
    Kemp:
    So I'm expected to believe that it worked fine sending data to his logging app over the serial port for a while and then suddenly Windows decided it was a serial mouse? Is this even possible? To my knowledge Windows doesn't try to interpret the data being sent back and forth in these scenarios purely because it could be absolutely anything, that's up to the app to know what to do with. Any supposed magic byte sequence would be sent eventually no matter what you hooked up (assuming you were sending purely binary data, text data could most likely hit it too if you used characters outside the A-Z, a-z and 0-9 range).

    I think it's the rebooting that added the serial mouse, as it tries to do autodetect then. I think whatever his problem was before the reboot is still an unknown.

  • RogerWilco (unregistered) in reply to PPP
    PPP:
    It's not DAQ, but DAC. (Digital to Analogue Converter).
    Except that National Instruments calls their DAC stuff NI-DAQ, so the article is quite right as it mentions this hardware ;-)

    http://sine.ni.com/nips/cds/view/p/lang/en/nid/1037

  • Err... (unregistered) in reply to PPP
    PPP:
    It's not DAQ, but DAC. (Digital to Analogue Converter).

    No it's not. National Intstruments call their DAC boards Data AcQuisition cards (NIDAQ). Trust me, I've used them.

  • Err... (unregistered) in reply to Err...
    Err...:
    PPP:
    It's not DAQ, but DAC. (Digital to Analogue Converter).

    No it's not. National Intstruments call their DAC boards Data AcQuisition cards (NIDAQ). Trust me, I've used them.

    Oh, and they're primarily ADCs, not DACs anyway (though I think some of them have outputs as well).

  • MC (unregistered) in reply to Ken

    Bingo! And actually LOOKING at that standard, I see exactly what's wrong.

    Windows tries to support pre-1995 mice that do not have a distinctive ID string. Note that the standard says that the ID of a serial mouse could be almost anything.

    Please, Microsoft, stop supporting pre-1995 serial mice!

    The other thing that comes out is that our hapless victim's PC must have rebooted over the weekend. All indications are that serial port enumeration takes place only at bootup.

  • MC (unregistered) in reply to MC
    MC:
    Bingo! And actually LOOKING at that standard, I see exactly what's wrong.

    Windows tries to support pre-1995 mice that do not have a distinctive ID string. Note that the standard says that the ID of a serial mouse could be almost anything.

    Please, Microsoft, stop supporting pre-1995 serial mice!

    The other thing that comes out is that our hapless victim's PC must have rebooted over the weekend. All indications are that serial port enumeration takes place only at bootup.

    Sorry, lost some context. I was referring to the Plug and Play standard which someone pointed us to: http://www.osdever.net/documents/PNP-ExternalSerial-v1.00.pdf

  • Snow_Cat (unregistered)

    Think that having Windows mistake some random input for a mouse is fun?

    Windows' PNP periodically interrogates all of the legacy ports. This can be quite a learning experience if for example you are reverse engineering some very expensive hardware using, a parallel port that has carefully configured set to TTL mode (at 0-2.5v) to drive the target hardware. And Windows interrupts a few open driver handles to say "Hay Guys, Has printer? No?" And failing a reply switches to VDiff mode to shout "Wake up Mr. Printer!" (at ±13 V!)

    Certainly taught me to build a PCI interface rather than improvising one, and that a five-figure damage-guarantee on third-party device-drivers in writing was not only hilarious, but a very good thing to have had.

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