View Full Version : Acorn RISC PCs

January 6th, 2014, 09:03 PM
Hi. Does anybody in here know anything about Acorn's RISC models? They're scarce here in the US, but are they easy to find in the UK? I was thinking about trying to get an Archimedes. I've looked up the different models on Wikipedia, but maybe some of you could tell me which ones are the most interesting. As far as I know, we didn't have these in the US, so I'm really not familiar with them. Could all of the models run RISC OS, or was that only the later ones? Thanks!

January 6th, 2014, 09:27 PM
Dunno, but there may be a few Acorns wandering around--in the early days of Sibelius (the music transcription software), you needed one to run it before the Windows/Mac versions came out.

January 6th, 2014, 09:31 PM
I've got a few. Recorded my trials a tribulations http://www.vintage-computer.com/vcforum/showthread.php?23526-What-have-I-done&highlight=Risc+PC

There are some very good resources out there. I recommend you join up http://www.stardot.org.uk/forums/viewforum.php?f=13

Risc OS history http://www.wrocc.org.uk/riscos/history.shtml

January 6th, 2014, 09:59 PM
If you want to know what was available for Acorn risc machine hardware wise http://acorn.chriswhy.co.uk/

January 6th, 2014, 10:44 PM
Caluser2000: Thanks so much! You've directed me to some excellent sources of info. Interestingly, as I was googling earlier, I discovered that there is now a RISC OS distribution for the Raspberry Pi. Lots of emulators available too. Apparently the source code is now managed by a group called RISC OS Open, and there seems to be a lot of current interest in it.
Btw, how many of these machines do you have?? It sounds like you acquired quite a few!

January 6th, 2014, 11:02 PM
One A3000
One A410/1 which is extensively upgraded to almost A4000 specs
Three A4000s
Six RiscPCs in various configurations from 600 through to StrongArm.
Also have bit of add on hardware, such as PC Cards, roms, hdd cards and what not. I'm still on the look out for any Acorn Risc related stuff I can get.

Something a bit different to play with. I've still only scratched the surface though with regards my knowledge about them. RiscOS 3.11 appears to be the most compatible with older software from what I can gather. Acorn did make some weird design decisions. Now they're just interesting quirks.

The community is the same to any other that have folk interested in the similar things. Very helpful I've found. Hardware has even been developed to extend their capabilities a bit in some cases.

January 7th, 2014, 04:50 AM
They also had a model aimed at the home market (to compete with the Amiga 500 and Atari 520ST?) with joystick ports and a built-in RF modulator:


January 7th, 2014, 10:30 AM
The nice thing is the OS is in ROM. It was designed from the outset to read/write data to and from dos as well as atari formatted disks. No need for extra software or hardware. The ability to adjust the ram drive size on the fly is a nice feature as well.

January 7th, 2014, 11:17 AM
Wow, Caluser2000, you have a lot of Acorns. Maybe we should call you OakTree. (Sorry, couldn't resist.) Which OS does your A410 have?
These really are interesting machines. It looks as if the A30X0 models are not very easy to find.

January 7th, 2014, 11:35 AM
The 410/1 has RiscOS 3.1 roms. I'd imagine that was done when the previous owner updated it with the MJE Micro ARM3 Booster CPU, 4 megs of ram and IDE podule with a 170meg IDE hdd. It is still limited to a 3.5" DD fdd through the on board controller though.

I know they were'nt popular in the States. There were issues with dealing with strict RF reg. though. There's no sheilding at all on the RiskPCs. The special paint doesn't cut the mustard so to speak. Primary use for Acorn Risc machines was in the educational sector in England, Australia, NZ and a few other countries. In saying that few saw use in the scientific community as well as in production use.

You could call Acorn Risc machines my mid-life crisis machines. A few NZ VCF members were lucky enough to score some of these boxen from a local chap who was clearing out a school lot.

Post A4x0 series models, including all-in-ones from A3000 up, do suffer from battery damage on the mobo. They don't like being left a decade without being powered up either.

One thing about them though is that documentation and help is readily at hand. Can't say that for my recent purchase, a Zenith Z286LP Plus. It's like some cloak of secrecy had been draped over them, well their x86 systems in general and one reason I started a thread up about my experiences.

January 7th, 2014, 11:32 PM
Yes, I've read in a couple of places about battery corrosion on these machines. And I am a huge fan of proper documentation. That will be a big bonus for me if I ever manage to get my hands on one of these Acorns, because for me it will be an entirely unknown new species. Sorry you're not having any luck finding info for your 286. Not sure what you're looking for, but if it's things like jumper settings, maybe this will help: www.uncreativelabs.de/th99/m/U-Z/34128.htm. I'll have to go take a look at your Zenith thread.

In any event, thanks to all the information you've shared with me, I'm now actively searching for an Acorn. Unfortunately, the closest ones I can find are in the UK. Maybe if I pick up more than one of them at a relative discount, the shipping won't be quite so onerous. I'd like an A30x0, certainly, because it really is an unusual machine for its time. Which of the later models do you like best?

January 8th, 2014, 08:18 AM
The RiscPC for it's expandability/upgradability. The reality is anything more than two slices is a right pain. A4000s with RiscOS 3.1 roms for software compatibility with older titles and take a vga monitor. Wouldn't mind getting hold of an A7000 Plus just for the fact they take ps/2 keyboards and mice. They're a poor mans RiscPC but I'm quite fond of small form factor desktop machines.

Good luck with your quest. I'm sure you will get what your after.

January 8th, 2014, 09:42 AM
Can you tell me if the PSU of the A3000 is integrated into the mobo? Apparently it is on the A3010 and A3020, but I'm finding conflicting info on the A3000. Thanks.

January 8th, 2014, 09:50 AM
It's built-in to the unit but seperate from the mobo. You just plug the plug on the power lead into a power socket http://acorn.chriswhy.co.uk/Computers/A3000.html#A3000I3 Of course being from the UK it'll be set up for 240 volts.

As I mentioned earlier Chris's site is probably to best consolidated Acorn site to look for info.

January 8th, 2014, 10:05 AM
I was wondering if I can change it out. We're 120V here. Apparently, at least on the A3010 and A3020, the PSU is literally part of the mobo. I've just found a site where the service and technical reference manuals are available for all of Acorn's RISC OS machines: http://www.drobe.co.uk/reference/trm.php
I'm sure you already know about it. I see what you mean about the availability of documentation for these models. It's relatively easy to ferret out info.

January 8th, 2014, 10:21 AM
I'd imagine a suitable step up transfomer wouldn't cost terribly much these days.

The A3000 psu may well be switchable. Found this thread, second page, post 24 http://eab.abime.net/showthread.php?t=44026&page=2

January 8th, 2014, 11:13 AM
On the page you linked to in the A3000 technical reference, page 19, it confirms the A3000 psu is voltage selectable and gives you more detail how to change it. Of course you'll have to change the plug as well.


January 8th, 2014, 11:30 AM
Thanks. I have confirmed per the TRM that the PSU in the A3000 can be set to 120V. The optimal solution. So I don't have to replace the PSU and I won't have an ugly brick (transformer) as part of the setup. :D Time to go see what I can find for sale in the UK...

January 8th, 2014, 11:49 AM
Ahhh the trill of hunt lol. Another Acorn nut on the loose ;)

January 8th, 2014, 01:19 PM
Aw, we cross-talked on the manual. We must have both found it at the same time. That was awfully nice of you to look it up too. Thanks.

There are just a couple of A3000's on eBay UK. Both are functional, but neither one is cosmetically stunning. And no other RISC PC to be found! These creatures are rare even in their native habitat. I guess I'm going to have to stalk them through the forums and hope I can take one by surprise. Back to the interjungle, then.

January 8th, 2014, 01:29 PM
CJE Micros http://www.cjemicros.co.uk/micros/prices/categories/computers.shtml#secondhand and ADPL http://www.apdl.co.uk/comps.htm#computers have a fair selection if you aren't terribly worried about the cost.

January 8th, 2014, 02:05 PM
Well, you led me to a whole herd of them! The prices for the newer machines aren't bad. So...much...homework...to...do...
Thanks and cheers!

January 8th, 2014, 05:19 PM
That's ok. "But Wait!! There's More!!" There's a nice compilation of software done by a chap around Risc OS 3.1 that called "Classic Risc OS" with some later updates to pretty things up a bit- http://qubeserver.com/Qube/classicriscos.html One compilation has an emulator built in. There're also some emulators linked to on the home page. Some other interesting upgade/projects on that site as well.


I see he's started on a Risc OS 4 version for RiscPCs since I last visited. Must look at that.

January 8th, 2014, 07:33 PM
People really like this OS. It's turning up in all kinds of hacks. I'm looking forward to playing with it. I remember the RISC vs CISC debate that really came to a head here in the US in the early 90s. I even bought a Power Mac with a PowerPC processor, which was my first Mac. (I didn't like it, but that had nothing to do with its performance. I was just horrified when I realized I couldn't even get inside the case to add some RAM.)

Acorn was ahead of that curve; they introduced the first Archimedes, which was a 32-bit RISC system targeted at home users, in 1987. That's pretty impressive. I've known about ARM for many years, but I didn't know until 2-3 days ago that ARM actually means Acorn RISC Machine. And it all started with the BBC Micro. What a great story.

One of my UK contacts is offering me an A7000 along with the A3000. I'm not sure of the specs, though, or the condition of the machines. I'm also going to get in touch with the suppliers you mentioned (for which I thank you again). Apparently they sell new old stock. Since I'm going to all the trouble (and expense) of dragging this stuff over here, it might be safest to buy unused equipment. Interestingly, it's all old enough that there's no VAT. So being a vintage collector apparently has tax benefits!

January 8th, 2014, 08:02 PM
Be careful you don't get called a toffee nosed snob by all those commoners with Amiga, IBM PC clones and Apples. I look forward to see how you get on. Who knows, it could be the start of a wave of Acorn risc machines heading over the pond.

January 8th, 2014, 08:05 PM
Oh dear. The colonists are pillaging the island.

January 8th, 2014, 08:12 PM
If you like the Acorn and similar UKan hardware, you may want to look into the ICL PERQ from about 1981. Bit-slice, microprogrammed beast, remarkable in terms of technology.

January 8th, 2014, 08:54 PM
If you like the Acorn and similar UKan hardware, you may want to look into the ICL PERQ from about 1981. Bit-slice, microprogrammed beast, remarkable in terms of technology.http://toastytech.com/guis/perq.html http://toastytech.com/guis/pemu.html

You'd need to ship over a PERQ 1 on a pellet.

January 9th, 2014, 02:23 PM
But it would look so nice sitting next to my Xerox Alto.

A tidbit from the DigiBarn page on the PERQ: "April '83 Byte "Seive" benchmarks: PERQ is 7th fastest machine on the list, blowing away all but the biggest Crays and IBM mainframes"

Some info on the hardware is here: www.chilton-computing.org.uk/acd/sus/perq_pr/p002.htm

January 9th, 2014, 02:40 PM
I was reading up them last night thanks to Chuck.. Interesting systems alright. I'm surprised they don't get mentioned more often. How long have you had the Alto FL?

January 9th, 2014, 03:07 PM
You'd need to ship over a PERQ 1 on a pellet.

I did call it a "beast".... :) The hard drive looks like a Shugart SA-4000.

January 10th, 2014, 12:52 PM
CalUser, I've had the Alto in my imaginary collection since sometime in the late 1980s, when I first read about it. Which is where it is destined to remain.

Chuck, congrats, you are the winner of name-that-drive. That PERQ had a 14" 12- or 24-MB Shugart SA4000 hard disk drive.

The PERQs are way too interesting to remain buried as an OT aside. If they don't have a thread in here somewhere, I'm going to give them one.

Elsewhere, on the Acorn front, my real life interrupted my collecting activity today, so I didn't manage to get in touch with the Acorn suppliers before end of business in the UK. Anyway, I still have to decide which of the later RISC PCs to get. I seem to remember reading something about a bus limitation in some of those systems.

January 10th, 2014, 08:37 PM
I just find Acorn risc machines interesting warts and all. Anyway all the info you need is at your figure tips and good luck in what ever direction you decide to go.