And on top of what George says, it might be best to make sure the printer is on the same breaker/120Leg as the computer. If the computer is on a UPS and the printer is not then if possible make sure the printer is plugged into the same outlet as the UPS. Also note that I don't know which power system you are on, I am familiar with the US hot/neutral/ground 3-prong plug which is supposed to just work for this, but there are a number of mis-wirings (of both the outlet and the device) that are common enough to not be unlikely. In the US there are simple <$10 devices (most hardware stores) that plug into outlets and light up and tell you if the outlets are wired correctly. Weird ground issues produce really odd behavior. If everything involved is using a proper ground outlet and the outlets are properly ground and all of the devices are properly wired then you should not have a weird ground issue, which is what this sounds like, and was why Geroge mentions running a wire to make sure the ground is right. If you have a multimeter you could check resistance between a metal part on the printer and a metal part on the computer without the printer cable attached, if everything is right the resistance should be almost 0, if the resistance is not almost zero then something really is wired wrong. If the resistance is non-zero then there is a decent chance that the ground on one device vs the other could be a few volts difference (you can also check that with the meter, but it may or may not be different enough at the moment), with a small amount it will think there is a signal when there is not, and with a larger difference any electronics (the parallel port card) may burn because there is current flowing were it is not designed to flow. On Tue, Oct 6, 2020 at 10:46 AM George N. White III <gnwiii@xxxxxxxxx> wrote: > > On Tue, 6 Oct 2020 at 03:03, ToddAndMargo via users <users@xxxxxxxxxxxxxxxxxxxxxxx> wrote: >> >> On 2020-10-05 19:20, Tim via users wrote: >> > On Mon, 2020-10-05 at 17:15 -0700, ToddAndMargo via users wrote: >> >> I think I am going to replace the parallel port card >> >> "just because" >> > >> > If your parallel port is on a card, then simply removing the card ought >> > to show whether *it* is the problem. >> > >> > Peripherals are a prime area of hardware failure. When you have two >> > mains powered devices hooked together, and one or more of them isn't >> > earthed, or you connect them together while the equipment is on, it's >> > very easy to zap components. They mayn't die instantly, but can be >> > weakened. >> > >> > Peripherals connected between buildings, or even between rooms, also >> > suffer the same kind of risk. >> >> It decides when to poop out. It is not all >> that easy to reproduce. >> >> Basically, it poops out when I need it the most. > > > Run a wire (at least 18 gauge) from the chassis of the PC to the chassis of the printer. > This should greatly reduce the chances for the parallel port getting zapped. You might > also think about using a more modern interface, with USB to parallel converter or adding > a network interface to the printer and disposing of the parallel port. > > > -- > George N. White III > > _______________________________________________ > users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx > To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx > Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ > List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines > List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx
