Didn't Psion use H8?
What to do with a ton of old Hitachi H8 MCUs?
Hitachi's microprocessors became part of Renesas. You might be able to find additional documentation on the Renesas siteThere's a gcc for H8: https://gcc-renesas.com/h8-legacy-toolchains/Datasheet: https://www.datasheets360.com/pdf/864743618009682633(Your photo shows 84pin plccs, BTW.)My advice: throw them away. There isn't enough time in the world to spend working on dead-end architectures, without even hobbyist history behind them. If you want to play with something old, get a Z80 or 8051 (the 8051 architecture is still in common use.)Also, those are PROM-based chips, not flash, and not eraseable, so you get ONE chance to program them (assuming that there isn't already code in them...) (and it probably requires a programmer with weird programming voltages.)
Yes, gamma. I had access to a professor who had a cobalt-60 source
Now that's a neat toy! How beefy of a source was it? 1 uCi sources are readily available and safe to handle, but Co-60 sources powerful enough to be "self-protecting" exist (used in industry for sterilization, and in medicine for cancer treatment).