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RISC OS 4 vs 5 FAQ

By Chris Williams. Published: 5th Mar 2003, 06:45:27 | Permalink | Printable

Who's doing what with what [Updated 5/3/2003 10:18AM]

Ever since the breakup of Acorn, RISC OS as an operating system that historically "does more with less", has shown that it can still continue to exist and progress in terms of continued development, third party involvement and finding newer architectures to reside on. Even though RISC OS is evolving and gradually shifting away from the golden oldie RISC OS 3 days and the dutiful-but-its-really-had-its-day Acorn chipset, a shadow of mild confusion appears to have been cast by recent(ish) events and several questions have been raised by users relating to where RISC OS is going and who's at the helm.

Or to the point, what's the deal with RISC OS 5 and RISC OS 4, especially now with RISCOS Ltd.'s managing director's revelation last month about RISC OS 5? So we've pooled our information together and made an FAQ which will answer any queries. If you think we've left out something, let us know.


Who owns RISC OS?
This is a complex issue, so forgive the slight simplification applied here. After Acorn was broken up in 1998, the big UK set top box company Pace eventually accquired the rights to RISC OS; they effectively own it and licence it out to other people as well as in the past embedding it in their own products albeit for a short while.

So where does RISC OS 4 come from?
RISCOS Ltd. was formed soon after Acorn's departure to continue development of RISC OS for desktop computers and as such, develop and distribute their version of RISC OS under an exclusive licence with Pace. The RISCOS Ltd. version of RISC OS is RISC OS 4, licenced exclusively for desktop machines with the latest version being 4.33, available from the Select scheme.

What does RISC OS 4 run on?
RISC OS 4 runs only on 26 bit Acorn chipset based computers, ie: RiscPCs, A7000s, RiscStations, Microdigital Micos and reportedly yet unofficially at the moment, the Microdigital Omega (still awaiting public release). Newer ARM and ARM compatible processors no longer support the 26 bit address mode and instead use a 32 bit addressing mode. As explained here, RISC OS must become 32 bit compatible to run on newer processors.

So where does RISC OS 5 come from?
RISC OS 5 is developed and distributed by Castle Technologies for their range of Iyonix computers. From its official launch, Castle stated that RISC OS 5 is derived from Pace 32 bit work and also copyright of Pace, that is, it didn't come from RISCOS Ltd. Castle's managing director Jack Lillingston also stated during the Iyonix launch that Castle has the source code to RISC OS 5 and is actively developing it. The current version of RISC OS 5 is 5.02.

What does RISC OS 5 run on?
RISC OS 5 runs purposefully only on the Iyonix range of computers. The Iyonix is a purely 32 bit machine as it uses the 600MHz Intel XScale processor, it therefore requires a purely 32 bit OS, namely RISC OS 5. Incidentally, the Iyonix processing core was benchmarked this week by drobe.co.uk.

Who's developing RISC OS for us users then?
In summary, Castle and RISCOS Ltd. Castle work on RISC OS 5 for their Iyonix computers. RISCOS Ltd. work on RISC OS 4 for 26 bit machines like this editor's RiscPC.

Uh, what's the point in developing OS 4 if it runs on old systems? Surely development should be in OS 5?
Firstly, people still use their RiscPCs and other 26 bit computers and as long as they do, RISCOS Ltd. have said they'll continue developing RISC OS for 26 bit computer users. Secondly, despite RISC OS 5 being 32 bit (a major break through and something Acorn didn't attempt to our knowledge) and possessing the ability to use newer architectures such as PCI and USB, it is not as feature laiden as the latest versions of RISC OS 4. Therefore, it's hoped that in the near future a 32 bit version of RISC OS Select will be produced for RISC OS 5, bringing both version streams in line.

Understand that we're not playing down RISC OS 5 here (we're assured by many users that it's all fine and dandy), we're just underlining the immediate concern that there's now two streams of RISC OS being actively developed by two different companies.

I'm an Iyonix user and I miss features from Select on my RiscPC. When will there be a 32 bit version of Select for RISC OS 5 users?
Castle implied during the Iyonix launch that they wish to stabilise RISC OS 5 and make it rock solid before enhancing their version of the OS with RISC OS Select goodies. This may still well be the case.

What's stopping RISCOS Ltd. from doing what Castle did and get a 32 bit RISC OS and make a kick arse 32 bit version of RISC OS Select?
Now here's the biggie, and we cautiously suggest, almost controversial bit. Remember that RISCOS Ltd. have stressed that only they possess the exclusive right to distribute desktop incarnations of RISC OS, as per their licencing agreement with Pace. Taking that into account, one instantly wonders how Castle can distribute RISC OS 5 in their Iyonix desktop computers. That's easy. Castle obviously have an arrangement with Pace, right?

It's emerged this week that Paul Middleton of RISCOS Ltd. told the Archive magazine mailing list last month that they have written confirmation from Pace that there has not been a 32 bit RISC OS licenced to anyone, throwing into doubt the origins of RISC OS 5. If that's not a bombshell then we certainly don't know what is and we stress that we're not siding either way. It answers the above question though, according of course to RISCOS Ltd.'s explaination.

Update [5th Mar 2003, 10:18AM]
After the above FAQ was published, Castle replied to our email emphasising that "Castle have all the necessary licences to produce and sell the RISC OS desktop computers: the RISC PC, the A7000+ and the IYONIX pc", adding that they felt Paul Middleton's statements were "misleading".

We'll leave you to call this one.


Castle RISCOS Ltd.

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Next: Websites round up


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Misleading? Is that all they claim? Can't they say the statements are definitively false? Can't they sue for libel? If Paul M was wrong, wouldn't that also piss Pace off? All this pussy footing around and "I'll leave it up to you decide" nonsense is really pissing me off! -- Gavin Smith, Carrickfergus

 is a RISC OS UserSparkY on 5/3/03 10:47AM
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Yes, it is incredibly annoying that Castle just won't answer the question. Do they have a 32-bit RISC OS licence from Pace, yes or no?

The fact that they have said that Paul Middleton's statements are 'misleading' - only seems to suggest that perhaps there is some truth in them. Otherwise they would have simply said the statements are incorrect.

I have a RISC PC, and at some point I would like to buy a new RISC OS computer. But while companies continue to mess around, I am just not willing to do it.

 is a RISC OS UserWalks on 5/3/03 10:53AM
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Oh, drobe with the controversy. It's arguably a much bigger bombshell than the GPL thing.

Castle cleared that up within a few days once it had gone public, maybe they'll do the same here.

 is a RISC OS Userflibble on 5/3/03 12:03PM
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But what's most annoying is people getting wound up and thinking all aspects of a company's business details are their own personal business. Dig in any company and you find dirt.

Both these companies are making products. Chill out.

-- Peter, drobe.co.uk

 is a RISC OS Usermrchocky on 5/3/03 12:04PM
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Would be nice if somebody from Pace could clear up the licensing issues once and for all. It would appear that having lost the arugment with VA. Paul Middleton is stirring it all up again with Castle.

On the other hand if he has something concrete then rather than grunting about it, surely he should instruct ROL's lawyers to sort it out. If Castle in breach of ROL's contract with Pace, they should seek an injuction to stop Castle furnishing the IYONIX with RO5.

By the same token, if PM is wrong then Castle should need to take steps to prove they have an appropriate license and prove PM is talking out his arse.

If however Castle do have a license that is in breach of ROL's license, then I suggest this be put in the hands of lawyers acting on behalf of all 3 parties so that resolution can be found.

Whatever they do it needs clarifying and doing quickly. -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 12:07PM
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The only thing I can think of is that Castle can develop RISC OS 5 somehow under their licence for RISC OS 3.7 which was signed with Acorn (or E14?) before ROL existed. ROL's contract is "exclusive" but Castle already had a licence. Maybe. Or not.

I want to buy a new RISC OS computer, I obviously want the best one, and it's difficult to decide at the moment who to go with if the Iyonix won't have Select features any time soon. We'll see.

 is a RISC OS Userben on 5/3/03 12:35PM
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sa110: Castle don't have to prove anything, ROL don't have to prove anything, Pace don't have to prove anything. It's up to them to sue each other if they think it's worth it...

nice cheerful thought that.

 is a RISC OS Userflibble on 5/3/03 12:42PM
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3 way law suite. I'm sure their lawyers will be happy. -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 12:48PM
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Ben good point about 3.7. But could Castle have afforded to employ the man power to do all the programming work? -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 12:49PM
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Cue flibble: "It hurts my eyes!"

-- Peter, drobe.co.uk

 is a RISC OS Usermrchocky on 5/3/03 12:50PM
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Mrchocky, who's wound up? We would simply like to know who is right? -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 12:50PM
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The people here, by their huge long comments. "who is right" is unlikely to be clear cut, and it may be none of your business. No doubt someone will find need to complain about this too. As I said, chill out.

-- Peter, drobe.co.uk

 is a RISC OS Usermrchocky on 5/3/03 1:07PM
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You could just wait a little while, and see what happens... -- Ian Hawkins (g0tai), Monkston, Milton Keynes.

 is a RISC OS Userpiemmm on 5/3/03 1:09PM
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A huge long comment does not mean someone is wound up -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 1:15PM
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Erm, so is there an active user-base in MK then? -- Jamie Temple, Loughton, Milton Keynes.

 is a RISC OS Userjamie on 5/3/03 1:43PM
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You, Ian(g0tai) and me. So far all of 3. -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 1:54PM
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I can't believe you're all being so silly. Of course there are no new RISC OS licences. And there are no conflicts. It's obvious. Castle bought RISC OS Ltd.

D'uh -- Spriteman.

 is a RISC OS UserSpriteman on 5/3/03 2:41PM
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AFAIK Castle only bought Acorn's stock of RISC OS 3.7 ROMs, and I'm pretty sure they did not get a source code licence for it.

Unfourtunately I can not reveal my sources, so all the above should be taken as rumours, nothing more. -- Julian G. F. Zimmerle

 is a RISC OS UserJGZimmerle on 5/3/03 2:43PM
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Spriteman, that wouldn't be a bad thing. -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 5/3/03 3:20PM
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i'm happy as long as something good ends up as the finally product(s) from either company

 is a RISC OS UserTimothy609 on 5/3/03 6:25PM
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But can we take it that MD don't have source for RISC OS 4 either, which should make implementing the UDMA disk system somewhat entertaining.

To the best of my knowledge Omega uses a PC Southbridge just as Iyonix does - as drivers for these don't exist in RISC OS (but do, ahem, in Linux) could you comment if the drivers used by Omega are licensed under GPL ?

Or can we take it that Omega just uses PIO like Iyonix and uses the standard RO drivers ?

-- Annraoi McShane,

 is a RISC OS UserAMS on 5/3/03 6:32PM
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It burns my eyes

 is a RISC OS Userflibble on 5/3/03 7:13PM
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Good morning Mr Phelps.

The man you are looking at, Mr Jon Balance has recently gained control of a rival version of our top OS, if he contiues to sell this he will destroy the real RiscOS and all we've worked to produce. Your mission, should you choose to accept it, is to discredit Jon and remove his OS from the market. As always, should any of your programmers be caught or killed the secretary will disavow any knowledge of your actions.

Good luck Jim.

 is a RISC OS Usermavhc on 5/3/03 7:38PM
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Milton Keynes - more RISC OS users per square mile than in a field.

-- Jon Wright (Jonix), Great Linford, Milton Keynes

 is a RISC OS Userjonix on 5/3/03 11:05PM
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Stop it. You're hurting flibble -- Spriteman.

 is a RISC OS UserSpriteman on 5/3/03 11:57PM
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@AMS: AFAIK MD have source for some parts of RISC OS. But why exactly would they need any OS sources to support UDMA? They do not use ADFS (only fools would try to use that for fast mass-storage access), but IDEFS. And why should they have to use Linux sources? They are very skilled developers, why should they copy other people's work? Just because some other lazy developers of another company did so?

-- Julian G. F. Zimmerle

 is a RISC OS UserJGZimmerle on 6/3/03 12:17AM
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i saw one of the concrete cows using an A4 once.

 is a RISC OS Usernex on 6/3/03 12:52AM
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Lazy is hardly a fair description. Unless you happen to know the developers personally... -- James Carey

 is a RISC OS Userjmcarey on 6/3/03 2:17AM
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Sorry, it was already past 1am here and I've had a very stressful day, so I was probably a bit too harsh on them. Of course they were not lazy at all. But they still should not haven taken this shortcut in the way they did.

-- Julian G. F. Zimmerle

 is a RISC OS UserJGZimmerle on 6/3/03 8:19AM
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Nex, did you taste their milk? -- Paul Stewart, Bletchley, Milton Keynes

 is a RISC OS Usersa110 on 6/3/03 8:44AM
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Seems to me there's too many rumours and "sources" to actually get a clear picture.

Speculation is all very well, but it doesn't get anyone anywhere, and merely creates more unrest.

This really is the business of those working with RO, and nobody else. Certainly not worth people having a go at each other on here.

 is a RISC OS Userheds on 6/3/03 9:16AM
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Okay, okay. It really doesn't matter who has licences for what. What matters is how this will affect the relative merits of the Iyonix, Omega and (to a degree) the RiscPC with Select.

Now, I'm pretty sure that within 6 to 12 months the situation will be much clearer. So, unless you really want to buy a new computer in that period there isn't anything to worry about. :-) -- Spriteman - the Dont-Worry-About-Things-You-Can-Do-Nothing-About Dept.

 is a RISC OS UserSpriteman on 6/3/03 9:30AM
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i lost a tooth trying

 is a RISC OS Usernex on 6/3/03 9:57AM
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Pah. None of our business anyway.

 is a RISC OS UserSnig on 6/3/03 1:59PM
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The details *aren't* our business. However, you can understand people being concerned about it - if they haven't got a license (and I don't actually think that's true for one second) it could put the long-term future development of the product in question - and therefore, people who want to buy a new machine are justified in feeling slightly concerned.

As I say, I don't think that's true - but you can't really blame people for being worried.

 is a RISC OS Usermoss on 6/3/03 6:24PM
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If RISC OS as a platform is to have a future then only 32 bit should be 'seriously' developed. Continued development of 26 bit RISC OS for outdated machines will only accelerate the decline (don't misunderstand, I have a RiscPC and love it). However, if I could have Select to turn VirtualA5000 into VirtualRiscPC on my Athlon 1700, I might consider resubscribing to Select. The squabbling needs to stop and a concensus reached so that RISC OS can survive!

 is a RISC OS Uservorgykof on 7/3/03 10:37AM
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-- Martin Dixon, LEICESTER

 is a RISC OS Usermrtd on 7/3/03 1:34PM
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I don't know what all of the fuss is about! It's obvious isn't it?

The licence document for RISC OS 5 that came with my Iyonix is issued by Pace. Therefore Pace own the rights to RISC OS 5. Castle simply buy it from Pace and install it on the Iyonix. This is no different from Microdigital or RiscStation buying RISC OS 4 from ROL and installing it on their computers.

So there is no conflict with ROL's licence. RO5 support development is done by Pace, who own RISC OS.

-- Martin Dixon, LEICESTER

 is a RISC OS Usermrtd on 7/3/03 1:40PM
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