• Adding documentation

    Matt Callow • 08/07/2021 at 07:17 • 0 comments

    I've been adding some more documenation for the project. So far I've uploaded the schematics for the PAK reader and the prototype bluetooth link.

    I've also uploaded the PAK reader source to github

  • Serial Interface

    Matt Callow • 11/13/2019 at 00:41 • 0 comments

    Once, I had the CommLink software installed, the next step was to build the hardware. For this, I again turned to Jaap's site and the schematics drawn by Olivier Gossuin.

    (I'm not sure that the schematics are 100% accurate, but they where enough to help me build my own Comms Link)

    Since I had the software in a DataPak in slot C, I wasn't sure if it would work with the hardware in the top slot. Only one way to find out - build it and see.

    So I built a simple interface using just 2 ICs; a 74HC244 and a 74LS00 (I didnt have a 4011 to hand). I only connected RX and TX (no handshaking signals) and connected them to a USB to serial converter.

    It worked! I could communicate between my PC and the Psion at 9600 baud over serial.

  • DataPaks

    Matt Callow • 11/12/2019 at 11:05 • 0 comments

    I bought the Psion and a number of blank 32K DataPaks. I have no Comms Link so no means to get any data onto the Psion (other than typing it in).

    So, the first task was to build a DataPak reader/writer.


    Jaap's excellent website https://www.jaapsch.net/psion/ has all the information I needed to build a DataPak reader/writer. Using an adruino pro micro. This uses 8 pins as a data bus, 5  pins for control (RESET, CLOCK, OUTPUT ENABLE, SLOT SELECT and PROGRAM) and one to generate the programming voltage via a boost converter.

    With this, I was able to program the CommsLink 4.2 software into a blank DataPak.