The next meeting of the RISC OS User Group Of London will be:

ARX and the Acorn Palo Alto Research Centre
Presented by Jim Mitchell

Monday 18th May 2026, 7:45pm

The Duke of Sussex
(upstairs in the Petworth Room from 6.30pm)
23 Baylis Road, London, SE1 7AY
https://rougol.jellybaby.net/venue.html

Also online via Zoom, meeting open from 7.30pm

https://rougol.jellybaby.net/meetings/


For this month's meeting Acorn alumni Jim Mitchell will be Zooming in from
his home in California. Jim managed the ARM development team and was head
of the Acorn Research Centre in Palo Alto. This was where ARX, the
originally planned multitasking, multithreaded, multiuser operating system
for the Archimedes was being developed.

Very little has ever been heard about what happened there and how far ARX
was developed, except from their RISC OS rivals, so this is a unique
chance to find out all about it from the person in charge. We are also
hoping to be joined by several other members of the development team to
help answer questions.

While Jim will mainly be talking about his time at Acorn, before that he worked for 12 years at the legendary Xerox PARC where ethernet, laser printers, file sharing, the WIMP paradigm, and many more computing
concepts we now take for granted were first developed. Later he worked for
Sun and was responsible for the development of Java.

He has had an amazing career and we are very excited to have him along to
tell us all about it :-)


Directions to the venue by car (there is parking directly outside the pub
on Coral Street) and public transport (recommended!) are on the website:

https://rougol.jellybaby.net/venue.html

Or contact us to receive the Zoom link to the meeting:

https://rougol.jellybaby.net/contacts/

If you have attended any previous meeting, it's the same link this month.

If you need any further information, please contact us as below.

RISC OS User Group Of London rougol2026@helpful-demon.co.uk https://rougol.jellybaby.net/ @rougol.bsky.social 07970 211 629


_______________________________________________________________ a.m.conroy@argonet.co.uk, Moderator of comp.sys.acorn.announce.
Submissions to csaa@owlart.net
Related mail to csaa-request@owlart.net

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* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)