Macrodigital Omega

Hi

I have an MD Omega and I was just wondering how many folk on here have one and what stage are you at with it ?
Mine has 4.03 in “Rom” (or rather FPGA or wherever it is stored, there are no ROM chips on the board), and it softloads 4.39.
Network (either fast and flakey, or slow and reliable depending on driver….), Sound and Floppy all seem to work. It has been recently recased recapped and a DOM installed instead of the spinner.

*Help Macrod. tells me
Module is: MicroDigitalUtl 1.15f (01 Jul 2004) for Omega ©2000-4 MicroDigital Ltd.

However I know there is at least
Module is: MicroDigitalUtl 1.15h (09 Dec 2004) for Omega ©2000-4 MicroDigital Ltd.

and Possibly a j revision too. But I can seem to find anyone with the flash files.

It doesn’t seem to like the System updates from here and wails about toolbox modules being too old (Toolbox 1.60 – yes I know its a 2023 module but…) Have tried the HD4 build and no joy either.

I’m not trying to run RO5 (yet)

So, Omega owners, any one further on than me ?
Cheers

Andrew

If you are the AndyMc from StarDot, then you’ve probably already seen my comments from there:

https://www.stardot.org.uk/forums/viewtopic.php?p=353084#p353084
https://www.stardot.org.uk/forums/viewtopic.php?p=154039#p154039

Mine also has 4.03 in ROM and softloads 4.39. Why would you want to downgrade by putting RO5 on it?!? (ooh, controversial! :-)

Haha

👋 Hello again Bryan. Yep it’s me. I’m not specifically looking to put 5 on it. Just curious 🤔 I know a few owners aren’t on stardot very much
It would also be nice to get a more recent !Boot on it though, the one here works on my RO 3.1 machines 😉

If you want a bit of fun – how about the RPC HardDisc file.

You could try the RPC RO 5 softload.

Probley need the Filesystem 32bitted for the HD to work.

Someone here ‘Peter’ is trying to get a 26bit version of RO5 to work on a RPC.

It would also be nice to get a more recent !Boot on it though,

My understanding is that updating appropriate parts of the Boot is the purpose of the System download

I have had a 32bit RISC OS 5 ROM image booting to command prompt on my Omega. The only real issue is the lack of 32 bitted driver modules. The Omega makes a fairly good attempt at looking like a RiscPC/A7000+ to the OS. Things only really fall down when it comes to dealing with it’s PCI bus.

With a couple of tweaks the standard Harddisc4 image will also work.

Mine is waiting on new caps at the moment but once it’s fixed hopefully I will find the time to look into it a bit more.

Interesting project :-)

I presume you tried *Desktop

Does the keyboard/mouse work? PS2?

If so can you work out what modules need 32biting.

PS are you talking about replacing all the Capacitors?

PS are you talking about replacing all the Capacitors?

https://www.stardot.org.uk/forums/viewtopic.php?t=24395

From my machine’s recon – yes a full replacement of capacitors is recommended.
DaveeJHitchings divulges that Baildon Electronics’ Dave Prosser (his business partner) designed the Omega for Macrodigital – there’s a few interesting snippets.

I have had a 32bit RISC OS 5 ROM image booting to command prompt on my Omega. The only real issue is the lack of 32 bitted driver modules. The Omega makes a fairly good attempt at looking like a RiscPC/A7000+ to the OS. Things only really fall down when it comes to dealing with it’s PCI bus.
With a couple of tweaks the standard Harddisc4 image will also work.
Mine is waiting on new caps at the moment but once it’s fixed hopefully I will find the time to look into it a bit more.

Interesting

Answering my question – 2 x PS2 ports.

Some Ethernet modules to port to 32bit.

Was there a period of time of bad capacitors or do all electrolytes suffer from old age like us?

Has anyone thought of a way of using a USB Arc/Rpc podules with RO5 drivers – along with drivers for the Omega?

or do all electrolytes suffer from old age like us?

Almost all* do, especially if they’ve had significant periods when they were allowed to completely discharge. Glad to see folks realise it’s electrolytics specifically – other types don’t suffer this way.

• N.B. It’s not simply cheap vs. expensive ones, it’s a matter of luck. Some makes & types suffer worse than others, but the details only emerged with time, accelerated life tests often don’t really correspond with real life experience.

it’s electrolytics specifically

It is basically two long bits of foil a strip of something like greaseproof paper between, and the whole thing soaked in gunk (that’s the “electrolytic” part).
In time, the gunk dries up (can be accelerated by a poor seal and/or brutal temperature changes) and this can lead to the paper stuff degrading. When that happens it is possible to dump current (possibly mains) into two little bits of foil with not a lot between them. That tends react in a somewhat explosive manner. 😀

can be accelerated by a poor seal and/or brutal temperature changes

Indeed.

Another failure mode – the one usually brought on by long periods discharged (or even worse, reverse charged even if only by a volt or two) – is corrosion of the foil, which can cause mechanical damage to the paper, without the gunk actually drying up at all. (Similar problem to dendrites in batteries.)

Some Ethernet modules to port to 32bit.

IS there any of the Iyonix stuff that works ? There are two Omega Networking Drivers – 4.34 which is slow and moo but reliable. 4.38 which is faster but ‘Dies’ with use. The Chipset RTL139 flags as 32 bit, at least it does on mine, but I assume that means PCI (32bit) Bus rather than 32 bit drivers?.

In time, the gunk dries up (can be accelerated by a poor seal and/or brutal temperature changes)

Or excessive AC in the feed to the capacitor

That tends react in a somewhat explosive manner. 😀

Hmmm. Build a MOSFET power amp, ensure a nice dual rail DC feed, ensure the ripple is smoothed out with correctly rated caps across said rails…
…forget to ensure the caps are the right way round.¹

Spend next few weeks recovering the ‘fluff’ that held the ‘gunk’ and spend just a few hours picking the metal fragments out of the ceiling and patching the holes.

¹ Look, I was 11 (eleven) so a few small, inaccuracies would be expected.

1 Look, I was 11 (eleven) so a few small, inaccuracies would be expected.

I was 17 when I built a stereo pair of class B amplifiers with four EL34s, and output step down transformers wound on nice cores that had the right reluctance… but definitely didn’t have sufficiently large saturation fluxes. (I may have told this story before…?)

Strangely (or not so strangely, really) a barely audible, badly distorted whisper came out of my speakers. But all hell broke loose down in the common room, where the telly had gone on the blink, with snow instead of a picture, and my music playing loudly and badly distorted instead of the programme. Apparently my music was playing on everyone’s tellies and radios for hundreds of yards in every direction.

In my younger days cruising electronics junk shops, I had something of a tendency for buying stupidly oversized capacitors (often salvaged from old equipment and dirt cheap) and dumping completely unsuitable amounts of power into them.
Think ~415VAC directly into something the size of a tea mug or coffee tin and rated maybe 25V and whole farads.
Very pleasing bangs (and clouds of what looked like fibreglass raining down).

It’s a wonder I’m still alive…

Taking this to Aldershot… “Youthful Indiscretions”

a stereo pair of class B amplifiers with four EL34s

Class B? Really? AB1 or AB2 were more likely, I’d have thought.

You’d need a negative grid bias supply to achieve class B operation.

See Aldershot – Youthful Indiscretions

If one compared the two modules to find the differences – is there anyone around here that understands the design of the Ethernet modules? [Edit]
After a walk – how alike are the various Ethernet modules – I seem to remember the RPC network card one was written in ‘C’ a bit tricky to 32bit with no source:-)

Just to drag things back

I presume you tried *Desktop

Does the keyboard/mouse work? PS2?

Unfortunately keyboard does not currently work

If so can you work out what modules need 32biting.

All the modules need attention but most look straightforward. The only one that has major concerns is the MicrodigitalUtils module. This is an odd creation that handles all the low level interface stuff and seems to be an extension of the firmware rather than a proper module.

Does the PS2 keyboard work under RO4?

Is there a serial port that can use a serial mouse?

Has anyone with a working Omega saved out the microdidital module?

Does the PS2 keyboard work under RO4?

Yes

Is there a serial port that can use a serial mouse?

Yes it does have a serial port but I expect it would run into the same issues as the ps2 port. Although I haven’t tried.

Has anyone with a working Omega saved out the microdidital module?

Once I have a working machine again I would be happy to.

Has anyone with a working Omega saved out the microdidital module?

Yes me, you’re welcome to it although as I say others may have newer. How do I get it to you ?

Andrew

Is there a website that can hold these Omega only modules / Utils?

Does RO6 softload ok?

(I suppose there isn’t a way of integrating Aemulor – so RO6 can run on the new RPi’s :-) )

What is the max RAM that a Omega can use – seem from StarDot – that you can fit 512Mb but only 256Mb can be seen/used.

The Omega can get a bit warm fitting some 1Gb cards.

Seems a bit like the RPC emulators being limited to 256Mb :-/

Can’t be done – sounds like they said to Brunel

Since the various Pi’s going up to 8Gb :-)