VirtualA5000 higher resolutions than 1024x768

I was experimenting with VirtualA5000 and I was disappointed that it doesn’t fit on my 1280×1024 monitor. I tried looking up for a patch, but none. I would like to run RISC OS 3.11 on 1280×1024 with 256 colors or higher. I would appreciate it.

Interesting. We had actual A5000s driving 1600×1200 monitors at the Journal of Physiology – in the 1990s…

Maybe with 4 colours, Clive! The VIDC can only DMA from the first 512Kb of physical RAM.

Interesting. We had actual A5000s driving 1600×1200 monitors at the Journal of Physiology – in the 1990s…

Pretty high tech, considering an average monitor at the time would be likely 800×600 or 1024×768.

The problem is that, I want to give the emulator higher resolutions to work with, 1024×768 in a 1280×1024 monitor looks odd with the letterboxes. I guess it’s possible by modifying the system files but I don’t quite sure how to get that high resolution, heck, I don’t even know if RISC OS 3.11 can handle much more modern resolutions like 4K or 1440p, heck even 1080p, without causing problems along the way.

Maybe with 4 colours, Clive!

Maybe, I don’t remember. Or did we have some extra hardware, maybe something Chris Honey produced? I thought we had 256 colours, on both the A5000s and the A440s.

@Stuart

Maybe with 4 colours, Clive! The VIDC can only DMA from the first 512Kb of physical RAM.

Lmao, it would be painful with that low count. It would probably fit with monochrome. That said tho, my install comes with the monitor definition files for a bunch of AKxx monitors which I wouldn’t figure out how to get it to work.

I don’t even know if RISC OS 3.11 can handle much more modern resolutions like 4K or 1440p, heck even 1080p, without causing problems along the way.

ROFL. It’s from 1992, like.

it would be painful with that low count

We’ve all been there we’ve when needed to.

The Physiology office – http://clive.semmens.org.uk/024_ROUGOL/P9.html – A5000s & A440s (later, also RiscPCs, but there are still A5000s and A440s in that pic) – all with 1600×1200 monitors. And definitely more than 4 colours!

Yeah, graphics card podule territory. VESA 1600×1200 dot rate is ca. 7x more than VIDC will do.

[I still have a Marconi Trackball on my RPC :-)]

So yeah, if someone can help adding higher resolutions in VirtualA5000 (or teaching me how to achieve higher resolutions in Arculator, an another Archimedes emulator), let me know.

The only lo-res monitor in that pic is the one attached to the A4 portable, which couldn’t drive the big monitors.

I have vague recollections of a Chris Honey card for the video, but very vague now.

[I still have a Marconi Trackball on my RPC :-)]

I still have a few Marconi Trackballs. I bought all the Acorn kit for a song when Physiology gave up doing its own pre-press, a couple of years after I moved to ARM. All gone now apart from the trackballs – two of which I converted to PS2, the rest are waiting for me to convert them to USB…far prefer them to mice, but I’ve got used to a trackpad on the Mac now, and wish I could have (a decent) one for the Pi…

Or did we have some extra hardware

Computer Concepts ColourCard, perhaps?

We’ve all been there we’ve when needed to.

Didn’t the earlier (?) versions of Sibelius use a four colour mode?

I’ve also done DTP work in MODE 0 (monochrome!) in order to have the maximum amount of memory available. Yes, it was painful, but more importantly… it worked.

Computer Concepts ColourCard, perhaps?

I honestly don’t remember. I have a vague recollection of dealing with Chris Honey, perhaps directly, and I think it was to do with graphics podules – or was he working for Computer Concepts at one time?

I should also point out, to stay on topic…

I was experimenting with VirtualA5000 and I was disappointed that it doesn’t fit on my 1280×1024 monitor.

The older versions of RISC OS, such as run on an A5000, only support numbered screen modes. In other words, this lot.

It is possible to have higher resolutions with the use of additional hardware, or custom modules that bash the VIDC; but you’re not going to get 1280×1024 out of a native A5000 due to the ~480K memory limit, and 1280×1024 is 1½MB. There’s also the issue of clocking, the VIDC in an A5000 running at 36MHz.

Anything better would require additional hardware, such as the ColourCard allowing 1600×600 in 16 colours (480K, within limits). Or that other one that completely replaced the standard video system.

That being said… Somebody on *. has managed to get 1280×720 (HD!) out of an A5000 by patching in a 48MHz clock, though they report it glitches at 51MHz and falls over at 52MHz.
So that’ll be a no to 1280×1024, but… 16 colour HD-res out of an A5000. Damn!

I ran my A5000 at 1152×864 on a Taxan 880 as that was the largest 4:3 16 colour mode possible.

Being a business customer I was lucky enough to be able to hand pick all the Acorn machines to get the maximum possible resolution for my personal use. I went through dozens of Risc PC’s to get on which did 1600×1200×256 colours stably under all conditions – which incidentally was the spec it was supposed to be capable of, until it was changed to 1280×1024 days before the official launch event.

A5000 at 1152×864 16 colour

That combination does ring a bell. 50 Hz I presume.

50 Hz I presume.

IIRC (not guaranteed!) our 1600×1200 monitors on A5000s and A540s at Physiology were running at 24Hz – possibly even interlaced at that frequency, I don’t remember. A similar trick to how I got 4K out of a very early Pi. And obviously with special hardware, a point I only vaguely recall – as I wrote, I vaguely recall a chap called Chris Honey, I think in that context.

All our RiscPCs – although Physiology was certainly a “business customer,” we certainly didn’t hand-pick anything – ran 1600×1200 without problems, but certainly with a mode definition file that I wrote, probably at 24 or 25Hz, I don’t remember. I think it was 256 colours not 16, but again, detail like that not guaranteed. If it was 16, there certainly weren’t 8 that flashed!

We only ever had one A4 portable, and I do remember that that had 16 shades of grey on its own screen, but could do 16 (I think) colours on an external screen. But only at some painfully low resolution; the poor lass who had to use it at conferences…

1152 × 848 does indeed ring a bell – I wrote a mode definition file for that in the very early days, when I first got an A5000 for myself, while I was still Director of IT at Highgate School, before I started the Physiology operation. That mode might well have been 25Hz (or perhaps 30Hz?), I really don’t remember.

How about using RPCEmu instead – with that one higher resolutions are fine (just the odd RISC OS Version might have some slight limitations as for e.g. 2560×1440 resolutions)

Or did we have some extra hardware, maybe something Chris Honey produced? I thought we had 256 colours, on both the A5000s and the A440s.

The options were: CC’s “ColourCard”, State Machine’s G8/G8+/G16 and TSPs PCATS. And an unreleased one from Switzerland that worked like the Amiga Flicker Fixer cards – would have to look that one up…

IIRC, Chris Honey was the hardware designer for the State Machine offerings back then. PCATS was Patrick Arnold IIRC. ColourCard was probably Peter Wild (WildVision)?

VIDC1 was hard-limited to 480KiB screen memory, so with a plain A5000 the only thing you could do was to clock it higher (VIDC Enhancer reloaded) than 36 MHz to get slightly higher frequencies, but that’s about it.

Getting back to things with Virtual A5000 then is it not supplied with iSV’s !ViVID5000 which enhances the screen resolution/modes available on a real A5000 and has the option to do a 1280×1024 mode?

The iSV site is currently offline but you could try searching the wayback machine?

Another thought is get a Raspberry pi, put the latest ROOL version on it and install ArcEM and then use ViVID A5000 or ViVID Lite and you can have a real RISC OS experience and also emulate a Archimedes as well with the required screen resolutions.

@Doug

The iSV site is currently offline but you could try searching the wayback machine?

This is what I got:

This URL has been excluded from the Wayback Machine.

Perhaps Vivid5000 was always a pay-extra product? I don’t remember it from my Virtual A5000 (which went to the bin a few months ago in a tidy up).

Virtual A5000 sales blurb states: “Support for 800×600 256 colour and 1024×768 16 colour screen modes”, as you’d expect as limits from something emulating a VIDC1.

get a Raspberry pi

Got a good dealer, Doug?