Quantity   Component name
1 × Arduino Nano or similar
1 × Header pins 2.54 mm pitch: one of 2x8 and two of 1x8 used for datapak connector
1 × Psion organiser II Datapak or Rampak Datapak for read or Rampak for read/write
1 × Psion Organiser II You could do this project without one, but why?
1 × Breadboard Electronic Components / Misc. Electronic Components
1 × stripboard or perfboard for the datapak connector perfboard is the best option, but I only had stripboard so I cut the tracks on the centre line
1 × for datpak write: NPN transistor, PNP transistor, 3x resistors, 2x PP3 connectors, 2x PP3 9 V batteries