"It belongs in a museum!"
#Psion #retrocomputing
Remote
The Last Psion | Alex
@thelastpsion@oldbytes.space
mastodon 4.7.2+glitch#Psion hardware/software hackery, especially SIBO/EPOC16 (Series 3, etc).
🔸 Made #PsiDrive, a USB drive for Psion SSDs using #RP2350
🔸 Slowly rewriting the SIBO SDK in #ObjectPascal #FreePascal (yes, really)
🔸 Co-maintainer of #plptools
⚠️ WARNING: WILL SIDEQUEST ⚠️
#HaikuOS, #Linux, #BSD, #MAME, #NeoVim, #compilers
Have old Psion source code (#OPL, C, C++, asm), docs or schematics? Please get in touch!
#RetroComputing #permacomputing #RightToRepair #OfflineFirst #luddite #CodeIsArt
937 Followers
137 Following
50 Posts
Joined October 11, 2024
Homepage:
Codeberg:
Psion Community:
One of the best AGENTS.md files I've seen so far.
Had a feeling you'd all like this. Not sure why...
Another one to add to the collection. And this one's seminal.
The Dragon Book.
Replying to
Another cool thing... The Zorkulator!
#RetroFest2026
I've started to put together a slideshow that will be playing at my table at #RetroFest. Here are early drafts of a few slides.
My current host has decided to vibe code their DNS management page. Needless to say, it's been broken for months. I used to get around it with their legacy cPanel access, but it seems they've disabled that for DNS management now. EDIT: I was being a moron - found zone management in cPanel. The crappy interface still stands.
I'd transfer my domains away, but they've vibe-coded the Registrar Lock bit, too, so that's broken.
And their first line support is an LLM which regurgitates the incorrect instructions from their documentation website. Instructions which, by the way, also look LLM generated.
Le sigh.
UPDATE: Got the EPP and transferred the domain to @beasts@social.mythic-beasts.com. I've heard so many good things about them, that I thought they were worth giving a go. Just waiting for DNS to update.
Replying to
Whenever I bring an Organiser II to a retro show, I feel a bit bad that I have nothing to demo on them. They're just a shiny 8-bit prop that would survive a small explosion.
But I saw this at #RetroFest2026. It's Pacman on the LZ! So now I've bought a copy of the Games Pack, so next time I'll be running it on my LZ64 for people to actually use.
At long long last, my blog is up and running!
I'll be bringing all of my old hackaday.io posts over as soon as I can, with some updates and annotations.
It'll mostly be about my #Psion adventures, but I'll also be posting information about the myriad sidequests I'll be going on.
Thanks to #CodebergPages for hosting it, along with https://psion.community.
"Alex, don't let anyone scare you away from that small Psion Wifi project. Because that rewriting the SIBO C SDK will be the best running a retrocomputing community of your life."
My #Psion netBook is working again!
I had to replace the fuse twice. Thanks to the first attempt, I'm now 99.999% certain that the old 15V Psion PSU has gone spicy.
I've ordered a USB-C PD adapter with a 4817 barrel jack at the other end.
If I have to do this one more time, I'm tempted to fit a replaceable fuse somewhere in the chassis.
One of my many sidequests is to try to get #NetBSD running on one of my #Psion Series 5mx machines. But I have a few issues/thoughts:
I'm struggling to find instructions on how to do this. (Can you help, @netbsd@mastodon.sdf.org ?)Because I can't find any instructions (granted, I was very tired when I tried last night), I'm a little worried that no one has tried this for quite some time.Both of my 5mx units and my working S5 are refusing to read any of my seven Compact Flash cards. Including the one that the netBook uses to boot. I have no idea how to fix that, and I don't really want to buy another 5mx as they ain't cheap.The winning 5mx will get a RAM upgrade to 32MB. (Yes, that's doable.)
If I can get something working, then that will encourage others in the #PsionCommunity to try. So we might actually get people running a modern OS on Series 5 machines. Also, as there are a good number of programmers in that community, we might get more eyes on the code.
Finally, if that all works out, then it might be possible to get it running on the (currently unsupported) netBook, too.
#Psion5mx #retrocomputing
OK, possibly daft #Helix question. How do I do the equivalent of Vim's yiw, yi"and yi(?
Replying to
@amoroso @smallsolar They did! Sometimes just the OS, other times as rebadged machines.
Psion licensed EPOC32 to two three companies - Geofox for the Geofox 1, and Oregon Scientific for the Osaris. EDIT: They also licensed it to Ericsson for the R380 (thank you to @aslakr for pointing this out).
As far as I know, Psion never licensed EPOC16 to anyone else.
But they did allow a few machines to be rebadged by other companies. For example:
Acorn Pocket Book (Psion Series 3)Acorn Pocket Book II (Psion Series 3a)Xemplar Pocket Book 3 (Psion Series 3c, so rare that I've never seen one for sale)Ericsson MC218 (Psion Series 5mx with some small improvements)Diamond Mako (Psion Revo Plus)
I'm sure there were others, too, but I can't remember them.
There were also custom versions of the 3a that still had the Psion logo but were also branded with other companies, such as the Prudential Insurance Company.
Does the term "Documentation Driven Infrastructure" exist?
You know, the idea that people have to write down how they're planning on setting up a network before they're allowed to touch a bloody server.
Days like today, I try to remember this quote from Ira Glass.
Programming is creative. In a world of LLMs, I think many people forget this. I work on projects because I want to learn. I want to create.
#CodeIsArt
RE: @lproven@social.vivaldi.net
The real lesson to take from this is about clean, maintainable, thoroughly commented code, which means that one developer can take it over from another even decades later.
Right, I'm not buying any more machines this month. I have plenty to bring with me to #RetroFest2026 now, including some really nice new things I've never shown before.
I just need to work out how to transport it all.
Oh, and I've got a French 3mx with a dead ribbon cable that needs either a screen swap or some soldering.
I might need some of those flight cases with the removable spongy bits.
Replying to
For those who are interested, here is that paragraph from the #Psion SIBO HDK.
Putting ASIC4 into SSD mode makes the chip compatible with all current versions of existing SSD software in production by Psion including all HC, series 3/3a and MC software. In this mode, ASIC4 mimics an ASIC5 in pack mode (see next chapter). This is because ASIC4 was originally designed to be a cut-down version of ASIC5 and so from the outset it was necessary to make previously existing ASIC5 software run on the new chip. The maximum address space in SSD mode is 21 address bits and 4 chip selects (which comes to 4 x 2Mb). In ASIC4 Extended mode, ASIC4 is capable of addressing up to 28 address bits (256Mb). In this mode, in addition to the Info Byte, a further 4 bits of information can be elicited from the state of the address lines A27-A24 during reset. Of these bits, the state of A27 (bit M) determines whether ASIC4 is going to be used as a standard SSD (M=0) or in a mixed mode (M=1) comprising of memory devices and peripherals. It is only the latter case which is of interest to the potential developer since this is the mode intended specifically for peripheral type expansion. In mixed mode ASIC4's address space is split into two equal halves. The lower half of the addressing range is set aside for memory-mapped peripherals and can be used for any purpose. The upper portion of the address space is reserved for pure memory.
Replying to
Mental note: Set a monthly alarm to make sure the batteries are still charged.
Replying to
@kianryan@oldbytes.space If you want more by @cyningstan@mastodon.social ...
BLOG: Make It Right - Next Steps With CTRAN
Rather than go straight into some of the more technical issues I've been facing, I've just written a quick recap on my rewrite of Psion's weird OO C preprocessor, and where I'm heading next with it and the rest of the SIBO C SDK.
https://thelastpsion.com/posts/make-it-right-next-steps-with-ctran/
#CTRAN #Psion #SIBOSDK
Replying to
Replying to
Replying to
It's been interesting to read through the old posts. Naive assumptions, hope that eventually led to dead ends, sudden bursts of productivity and then nothing for months. Periods of time when I'm sure I worked on something but I haven't written anything up, at least not somewhere public and open.
I'm not having a go at Past Me for any of this. Things ebb and flow, there will be dead ends and things I get wrong. But I am sad that I didn't post more.
We'll see what (and how) I do in the future.
Replying to
@netbsd@mastodon.sdf.org Thank you!
Replying to
@Gammitin I worked for a company around 2005 who had a fleet of these. I coveted them.
Having said that, I did have a T23 which was fantastic.
Replying to
I guess the fact that device selection bits can be moved means that the software doesn't actually have to care too much about devices. If the bits for selecting a chip are directly above the address space, then you can address them like it's just one contiguous block of data.
I just wish the bloody HDK had mentioned it!
Replying to
@shroomie Not yet, but I think the repo was only created last week.
Replying to
@ohmrun I know the repo owner IRL and have said exactly that to them already.
I might make a PR...
Replying to
@xorlou@lgbtqia.space That's really cool!
Replying to
@robertprice Ssh! No one's meant to notice that!
Replying to
@xorlou I have to say, @smallsolar does a fantastic job of repairing and refurbishing Revos. If you ever want another one, ask smallsolar.
Alas, poor Siena. They're pretty fragile as it is.
Replying to
@darth@silversword.online I'm mostly using various releases of various BSDs in VMs for cross-platform software testing.
I do have plans to experiment with FreeBSD on a couple of machines in my homelab, and to run NetBSD on a few unusual old computers. If I ever get the opportunity, I'd like to try OpenBSD on a ThinkPad X230.
Replying to
Replying to
@FrankauLux Actually, I hadn't. I do think Fuzix is worth trying, but there's already an official build of NetBSD for EPOC32 machines, so that should (hopefully?) offer an easier path. If that works, it might offer clues for other OSes.
Replying to
@dougbarry @beasts I don't normally do this sort of thing, but...
Replying to
@pulkomandy@mastodon.tetaneutral.net For different distro-hopping reasons I've been looking into Void recently. Don't know if it fits your requirements?
Replying to
@WiteWulf The first official build was NetBSD 7, I think. I'll probably start there and work forwards.
Replying to
@netbsd Thank you! I'll see what I can do with the kit that I have.
Replying to
@thejpster You know what? I've heard so much good stuff about Mythic Beasts, that I'm going to give them a go for this domain. Thanks for the nudge!
Replying to
@aslakr @amoroso @smallsolar Yes, the MC218, too! I knew there was one I forgot. I'll update the post.
Replying to
re: subpost about LLM discourse
Replying to
@gordoooo_z@hachyderm.io I don't know what you mean... 👀
Replying to
@FrankauLux I know there was an attempt to run Elks on SIBO - they removed most of the code a while back, but it's definitely there in older releases so could make a comeback. But SIBO machines are harder to cater for OS-wise. Not many people want to write an OS for 8086 anymore, let alone the NEC V30.
Linux does run on the S5, 5mx and netBook, but I believe the maintainer got ill and couldn't continue, and no one else took it on. ARM should be more feasible for other ports, too, even older ones.
EDIT: Linux for Psion ARM. https://linux-7110.sourceforge.net/
I think we're getting enough developers over on Discord that one of them might take on the work of porting/maintaining an OS if it was shown to be doable.