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1. Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:09:58 UTC Foone🏳️‍⚧️

   in reply to

   that large connector on the side is called "ISA" on the PCB.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:01 UTC Foone🏳️‍⚧️

     in reply to

     The keyboard is a rubber membrane onto the PCB, like a remote control. It's functional but feels pretty crap.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:03 UTC Foone🏳️‍⚧️

     in reply to

     The other chip on the keyboard/video board is an HM82C42. I can't find any info on this specific version, but it's almost certainly an Intel MCS-48 acting as a PS/2 keyboard controller.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:05 UTC Foone🏳️‍⚧️

     in reply to

     Next to it we've got a P25Q40H half-megabyte serial flash chip. This is presumably used to store configuration info for the RTD2660.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:07 UTC Foone🏳️‍⚧️

     in reply to

     So the keyboard PCB is also the display converter PCB. It stars a Realtek RTD2660, which is a standard video controller. It takes in analog video and drives LVDS displays with it. It's an all-in-one chip that's used on a bunch of cheap monitors, and it's also an 8051!

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:09 UTC Foone🏳️‍⚧️

     in reply to

     though I do want to show off this amazing bodge job.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:10 UTC Foone🏳️‍⚧️

     in reply to

     Assorted power regulation/charging circuitry that I'm not going to go into.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:12 UTC Foone🏳️‍⚧️

     in reply to

     A PAM8403 three-watt class-D stereo audio amplifier.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:14 UTC Foone🏳️‍⚧️

     in reply to

     A YAC512-M. This is a DAC used by the OPL3 to create the analog output of the audio chip.

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:15 UTC Foone🏳️‍⚧️

     in reply to

     There's three 74HC139s, which are dual 2-to-4 line decoders.

     This maybe is used for wiring up one of the expansion ports to the ISA bus?

   • Foone🏳️‍⚧️ (foone@digipres.club)'s status on Saturday, 03-Jun-2023 01:10:18 UTC Foone🏳️‍⚧️

     So over by the USB port, we've got a CH375B.
     This is an 8-bit IO chip for USB, specifically for storage.
     (it's also an 8051-based core! there's always an 8051)