Tom Stepleton

My issue with AI in the retro community specifically is that we don't need to talk to each other to get things done. It was lots of fun figuring things out together, getting to know each other as we go. Nowadays it's a stream of fait accompli "I made a thing!" posts. Feels passive, like watching TV.

Last week at #EMFcamp I gave a talk about the nothing-like-it-on-earth RSRE Flex operating system for #PERQ workstations. I'm very happy with how it came out! For a challenge, watch at 2X: media.ccc.de/v/emf2026-91...

Saturday 16:30 at #emfcamp Stage B: a talk I've been looking forward to giving for over a year. It's ambitious but if I pull it off I think it'll be a lot of fun. I want it to be a treat for computer history, OS, and programming language buffs, and for everyone else too!

Ah, the English springtime tradition of cutting out bits of metallised mylar space blanket and taping it over the window panes (In my experience it does help with sunny heat, especially for skylights!)

Please join me in praying that nothing else fails before the show. RetroFest 2026, Swindon, 30-31 May. You *might* see a working PERQ 2T2 there.

EIO board U48 CPU board U134 🎯

Patio. Rhymes with "ratio."

45 days until #RetroFest 2026 in Swindon. #PERQ status: - Flaky Z80-based I/O subsystem: sometimes the #Z80 jumps off the tracks and executes nonsense code - Disk boots fail: the microcode attempts to load blocks far beyond the end of the disk Trying today: DIY diagnostic microcode

POV: #PERQ hardware debugging, as usual. The #Z80 (serving as an I/O coprocessor) is behaving strangely: fetching instruction bytes without toggling the M1 pin, jumping to random locations at around 47uS after coming out of reset; what's going on here? RetroFest in six weeks or so...

I struggled with vi on the Torch. There's only one thing to do. Compile uemacs on the Torch. In the process of modifying the code to K&R formats I've started to like vi, rendering this task pointless. But now I've started I need to to see if uemacs will work. Why do I do these things to myself?

You want: a regular #Ethernet MAU to plug into an AUI port You have: a MAU that only works with Apple's weird AAUI port No problem! Here's an adaptor: codeberg.org/stepleton/aa...

This is the manual for the Elliott 803 library subroutine D2. It was implementing this sorting algorithm in 803 machine code that lead to Tony Hoare suggesting to his boss that he had a better algorithm, which turned out to be quicksort.

Rudimentary bootloader @adriansdigitalbasement.com ? I think it's fairly sophisticated! 😀 codeberg.org/stepleton/ca... All hand-coded 68k asm down to the text display (the ROM only has routines for UPPERCASE). Congrats on progress, it's been a blast to watch. PS: hit backspace during screensaver

PSA for Jan 1: www.fvap.gov remains a fine way for US citizens living outside of the US to request an absentee ballot without winding up on somebody's mailing list.

How I got an Apple Lisa to play audio samples: lisalist2.com/index.php/to... An extension of this technique: www.youtube.com/watch?v=3SlR... using a method also speculated by Adam Podstawczyński forgottencomputer.com/retro/sound/...

I'm recruiting a PhD student for autumn 2026 on a project on accessibility in musical instrument design, in partnership with disability arts charities OHMI and Drake Music. Application deadline 15 February 2026. More info and contact details: liss-dtp.ac.uk/project/inst...

Oh dear, could this be in regard to oldbytes.space/@stepleton/1...? I'd never say lithiums don't leak (I've seen enough Maxells and Tadirans to know better), but I still quest to find a BR-2/3A cell that has. It's the only exception, so I ask out of disbelief. Or was a better world always possible?

@breakintoprogram.co.uk so the problem with my Spectrum+ was the Z80, it turns out. The address bus was stone dead, +0V on all sixteen lines. Subbing in the CPU from my Jupiter Ace got it going; a replacement is now on order. Thanks for the chat on Sunday!

Just in time for #PERQtober ! An adapter to replace your missing or broken #PERQ T2 landscape monitor with a VGA display: codeberg.org/stepleton/pe... Thanks to @skeezicsb@oldbytes.space for early advice.

The Olivetti Programma P203 (1967) uses a circuit construction technique known as "transistor jail" (or "cordwood" [1]. Seen at [2].) [1] en.wikipedia.org/wiki/Printed... [2] www.thecomputerchurch.org

Wheeling Airglow (en.wikipedia.org/wiki/Airglow... ) out to the runway at the British Human Powered Flying Club's 2025 Icarus Cup event, Lasham Airfield, Hampshire.

Happy Pride #rc2014

#Smalltalk -80 on #PERQ --- Mario Wolczko's implementation (www.wolczko.com/st80/) running with maybe some gremlins still to sort out.

#PERQ PNX 5.03 manual pages at mg-1.uk/pnxman/pnxma... . The most interesting ones don't render very well with my hacked copy of a roff-in-JS "typesetter", but some interesting nuggets are there to reward persistence.

Grab your ear defenders, it's time to see the exciting features of 1986's PNX 5.03, the Unix for the #PERQ 2 workstation! Skip to 2:10 to bypass booting and go straight to the non-X11 graphics action! www.youtube.com/watch?v=TZRo...

Say, would anyone like to answer a newbie's gpg question? security.stackexchange.com/questions/28...

The EC2 instance is terminated and the AWS account cancelled. The site no longer links to larger files on Google Drive. Continuing to pull away from larger tech firms...

This is pretty funny to, like, maybe three people on Earth.