Transputer content on Twitter

A couple of twitter threads are up now, which promise some interesting info on the Transputer, for those who are (a) interested and (b) do the twitter thing.
Some intro and maybe a deeper dive.

Not sure if twitter threads are well-received here, let me know if this is unwelcome.


Thanks, interesting. Here are unrolled threads for convenience:

(See also here and here for a mirror on Nitter)

Interesting note in there:

I’ve got a tabletop Tektronix SS7 analyzer here that features a whopping 7 transputer cores on two enormous cards, used for analyzing telephone system traffic

Also this is interesting:

ISDN hardware saw a lot of transputers being used for example

I know Motion Media’s ISDN-connected videophone was based on transputer technology - but I think it might have used the last-gasp ST20 which was a microcontroller repackaging of transputer technology. It would still be programmed in the CSP paradigm - Communicating Sequential Processes - but those processes would all be running on the same single core, using the inbuilt hardware scheduler.

Among the places that Inmos got into trouble, in my view:

  • getting only half the requested bootstrap funding because of a change of government
  • pushing Occam for too long before supporting C
  • expecting CSP to be an acceptable paradigm… as cores got faster and shared memory became the norm, passing messages over external links became a bottleneck
  • failing to scale up performance, in part because a stack machine is difficult to speed up
  • losing all their chip design experience by taking too long and not retaining people, replacing with inexperienced engineers and managers
  • being in the UK where engineers are cheap but venture capital all but non-existent