Using the Psion 5mx as a Linux Serial Terminal
Tue Nov 5, 2019

Just a quick post today on how to use the psion 5mx as a serial terminal for your linux machine.

  1. Connect your psion 5mx to a serial port on your linux machine. If you have none, a USB adapter works fine.
  2. Find the serial port the psion is on. For me this is /dev/ttyUSB0.
  3. Make sure your user can access the serial port. For me on arch linux this was a case of adding my account to the uucp group.
  4. On the psion, make sure remote link is disabled. (Ctrl-L on the system screen, make sure it's off.)
  5. On the psion, open comms. Press Ctrl-K to open the connection preferences. These are the settings I use:
    • Comms port: Serial Port 0
    • Data bits: 8
    • Stop bits: 1
    • Parity: None
    • Leave "Handshaking" as-is.
  6. Pick a baud rate. Lower rates are slower but more stable, higher rates are faster but potentially more error-prone. Experiment!
  7. Back on your linux machine, run stty -F <Psion Serial Port> <Baud Rate> to set up the serial port.
  8. The Psion, by default, uses a VT100 emulation, but the emulation isn't great. export TERM=vt100 still works best, though.
  9. The Psion is now ready to be used as a serial terminal! For example, to run a shell on it, I'd use zsh < /dev/ttyUSB0 > /dev/ttyUSB0.
  10. Enjoy a fairly pointless and not great serial terminal!

The Psion 5mx as a serial terminal.

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