RISC OS 5.15 on VRPC

My only access to RISC OS these days is via Virtual Acorn. I’d like to do more work on the BASIC applications (Alarm, SciCalc, etc.), as well as the Theme manager, when time allows. Is the ROOL OS ever likely to be softloadable on to VRPC? I can appreciate that Iyonix/OMAP builds are likely to take higher priority, and that there may be political issues preventing making an IOMD build coming out soon, but I’d be interested to hear if there were any plans to produce a version of the OS for VRPC ‘hardware’.

Whatever political problems there may be, they don’t appear to have stopped ROOL hosting an IOMD 5.15(ish) build on the downloads page for the past few weeks. And that ROM image works fine in RPCemu – or rather, it works as well as it does on real hardware, which isn’t very well at all.

As of yet no-one’s stepped up to the task of fixing the HAL & other code to work properly for IOMD builds, so if you’re serious about running RISC OS 5 on an emulator then you’ll probably have to have a go at fixing it up yourself. IIRC the main problems were:

• A bug somewhere is causing NVRAM to be reset at boot. In particular this is preventing the ROM image from being set up to boot from HostFS, and is causing the mouse type to be reset to an incorrect value.
• RAM/VRAM detection & setup code hasn’t been migrated to the HAL, so you’re currently stuck with 8MB of RAM (and no VRAM?)
• The ADFS module (and probably a few others) need updating to cope with an arbitrary IOMD/IDE address instead of using a fixed one (or looking for a PCI IDE controller). Althought this is probably less of a concern for you if you’re just interested in running it under emulation (and your emulator has some kind of HostFS implementation!)

Hmm. That’s almost certainly going to be well beyond my capability to address (apologies if you’re sick of people saying that). I have a bit of BASIC expertise and some knowledge of Wimp programming. But, in the interests of Having a Go (or comedy, perhaps), I’ll take a look at the sources later this week.

Thanks for your reply!

I’d like to do more work on the BASIC applications (Alarm, SciCalc, etc.)

I’m currently working on Alarm/Maestro/PrintEd, so please don’t do any stuff without contacting me first or wait until I’ve delivered my changes to CVS.

Note I’m doing this development on RO4.02, I can’t see any reason why it’s vital to use RO5.1X to work on the basic applications (although it is desirable for testing).

James: Surely this is what version control is for?

I won’t have time to look at anything for a couple of weeks, but when I do I’ll certainly get in touch to ensure there are no toes trodden on :-)

And you’re right – there’s no need to have 5.15 installed just in order to work on these apps, but I’d prefer to be using 5.x as my OS rather than the pretty antiquated 4.02.

James: Surely this is what version control is for?

Yeah I guess. It’ll still be a lot easier for someone else to work straight off from my finished v2.80. Rather than produce their own forked version and then someone has to merge the changes together.

Also duplicated features could be a problem. So far I’ve implemeted modern save boxes and clipboard. If Chris deicided to work on those without knowing that I’d already implemented them, he’d just be wasting his time to no avail.