• merc@sh.itjust.works
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      18 hours ago

      The error message sounds bad, but it was actually a good thing. A better phrased error message might have been “Keyboard missing. Connect a keyboard and press F1 to continue.” But, in the early days every byte mattered.

      The system wouldn’t work without a keyboard, and if you get further into the boot process you might not be able to shut down cleanly if you didn’t have a keyboard attached. That error message gave you a chance to attach the keyboard, or to troubleshoot why the keyboard wasn’t being properly detected (like the plug got bumped and wasn’t making good contact anymore).

      It was annoying when the lack of a keyboard was intentional. Like, you wanted to use the machine as a server. But, AFAIK you could disable this check if you knew the machine was going to be a server with no permanent keyboard attached.

      • Deebster@infosec.pub
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        13 hours ago

        I was always told that you shouldn’t (dis)connect a keyboard when it was on because it could short circuit and fry something. This was before USB, of course.

        • merc@sh.itjust.works
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          7 hours ago

          Starting around the time of USB, they started designing plugs so that the parts of the plug that carried power were slightly longer than the parts that carried data so that as you plugged it in, the power connected before the data. That wasn’t something that was done with old connectors. In those, everything was the same length, so everything connected at once.

          OTOH, USB is a more complicated protocol than the old serial / keyboard protocols. I think generally systems were built well enough that you were unlikely to “fry” something by plugging in or unplugging something like a keyboard while it was running. Especially because the keyboards used low current and low voltage. And computers used big discrete resistors, capacitors, etc. back in those days. But, you could get some bad data on the keyboard line.

          • Deebster@infosec.pub
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            7 hours ago

            Interesting stuff about the plugs, thanks.

            I did quickly fact-check myself after posting and my brief reading suggested that it was possible to break the port, motherboard, or the peripheral, but that it was rare and more likely to cause corruption and/or crashes.

            E.g. some anecdata in https://superuser.com/questions/172420/is-it-safe-to-hot-swap-a-ps-2-keyboard and https://electronics.stackexchange.com/questions/50883/why-some-computer-peripherals-should-not-be-disconnected-without-turning-off-thi

            • merc@sh.itjust.works
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              6 hours ago

              and more likely to cause corruption and/or crashes.

              Yeah, that’s the neat trick they basically solved by making the power connectors longer. If everything connects at the same time, you connect the data lines while power is still coming up, meaning there’s a few milliseconds of data that you can’t really trust. If the hardware and software on the other side is designed to “trust” the data from the keyboard, who knows what could happen. Probably not something that breaks the hardware, but definitely something that can result in unexpected data for the software.

              But, just by adding a few millimeters to the power lines, you give a few milliseconds of power getting stable before data is attached, and that’s enough for things to be nice and stable.

    • palordrolap@fedia.io
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      1 day ago

      Way back, there were some rare keyboard / motherboard combinations where the motherboard couldn’t detect there was a keyboard attached unless a key was pressed on it. That message was for those people with those combinations.

      You pressed F1 and the computer would be like “my bad, there is a keyboard there, thanks for your help”, or rather it would just shut up and boot.

      The message could have been different but it had to fit in a small amount of BIOS ROM, so we got stuck with the one that covered all the bases the best, and unfortunately, most people who saw it didn’t actually have a keyboard plugged in, thus, irony.