ADFFS on RiscPC

[guibrush]

HI
I have a few questions about my riscPC on which I'm trying to run games using ADFFS. I'm just starting out in the world of riscPC (and the A3010 too, I've taken both machines), so I'm missing some basic notions that are probably obvious to you, I apologise in advance. I come from the world of the Amiga.

My machine is a RiscPC Acorn with a StrongARM 233 Mhz, 2 MB vram and 256MB ram. It has an icubed network card and a single IDE hard drive. The roms installed are 4.02.


I bought the upgrade to RiscOD 6.2 (but I have a feeling it was the wrong choice).

I installed ADFFS 2.83 and a few games. While some of them work, others give an error message



or an error message like this

or a black screen and hang the machine (Populous for example).

Reading the description of ADFFS, I now see that RiscOS 6 is not supported, but that RiscOS 5.x is required.

I see that this is not the same website that offers RiscOS 5.x, I found it here.

https://www.riscosopen.org/content/downloads/riscpc


My questions are as follows: why do I have to downgrade to be able to run the games? In other words, why is RiscOS 6 not supported anymore?

Is it really on this site that I should buy RiscOS 5.x?

Is this the cause of my problems running games, in other words, will installing RiscOS 5 solve the problem?

Can I just install the RiscOS 5 ROMs, or will I have a problem with the installation on the hard disk?

Thanks for your help.

[Sophira]

The thing to realise here is that this actually isn't a "downgrade", but essentially a move to a competing product.

RISC OS has an interesting history, but it ended up being that RISC OS 5.x is an actively-developed open source version of a product which used to be developed by Castle Technology (but now developed by RISC OS Open Limited), while RISC OS 6.x is a product that is no longer developed, but used to be developed by RISC OS Ltd (a different company, who also developed RISC OS 4.x).

Arguably, they both had rights to do this, which is where it gets complicated. I won't get into it here, but the important thing is that the latest stable RISC OS available, and the most well-supported, is RISC OS 5.28, not RISC OS 6.x.

[guibrush]

Ok, now I get it, thanks.
It is a good idea in my case to revert back and to the last 4.x working HDD image (I imaged my HDD before upgrading to RiscOS 6) and install Riscos 5? My goal is to be able to launch the games and if possibles demos too. I tried ADFFS on riscOS 4 and it doesn’t work at all, and on RiscOS 6 I have the errors I described in my first post.

Thanks

[dr_d_gee]

If ADFFS works on RISC OS 4.x (the last main version of RO 4 was 4.39, sometimes called "Adjust") then there's not a lot of point in upgrading to RO 5 on a RISC PC. Some of the traditional RISC OS software won't run on RO 5, because it was never made 32-bit compatible, without the assistance of a tool called Aemulor. There is a version of that which will run on a StrongArm RISC PC , but RO5 doesn't really offer any benefits on older hardware.

(The ARM was always a 32-bit processor, but RISC OS ran in 26-bit mode, where the flags take up the top 6 bits of the Program Counter, leaving just 26 — it seemed enough at the time. By the time Acorn was broken up, there weren't many processors available with this mode; Castle developed a 32-bit version of RO, based on earlier work by Pace, for its Iyonix PC — this was RO 5. Iyonixes were rare and unlike the RISC PC tend to be unreliable.)

RO 5 runs on various items of modern hardware, notably the Raspberry Pi — except for the Pi 5 which is 64-bit only. As RO is largely written in assembler, conversion, if attempted, will be very difficult. And not many programs are still being developed.

[guibrush]

now this confuse me. My problem is that ADFFS don't work under RiscOS4, and this is somehow confirmed in the thread of ADFFS here

https://forums.jaspp.org.uk/forum/viewtopic.php?t=624

"RiscPC requirements:
32MB RAM minimum
RISC OS 3.x, 4.x or 5.23 Jun 9th 2016 or newer. Note that some games will not work on RISC OS 4.x due to the way it allocates screen memory in 1MB blocks. RISC OS 6 is not officially supported"

I understand reading this that RiscOS 5 is better than RiscOS 4 because the way RiscOS 4 allocate the video memory is incompatible, and that RiscOS 6 isn't supported at all.

Now, I tested RiscOS 4 and can see that ADFFS give an error message when I launch it, and RiscOS 6, with the problems I described in my first post. I didn't tested RiscOS 5 because I still didn't understood how I have to install it.

Maybe it's better if I ask my question in another way: What is the best os to install on my RiscPC strong arm to be able to launch games and demos?

Thanks

[helpful]

Do NOT put RISC OS 5 on a RiscPC! It was never designed for it and will create massive software and hardware incompatibilities.

RO6 is the most advanced version you can put on there, but it came along very late in the RiscPC's life so was never well supported.

So practically RO4 is the best version to have, with 4.39 being the last of those with the most features.

Ironically, if you want to run old games, the best option is a Raspberry Pi with RO5.28 using ADFFS. The Pi's ability to scale any old screen mode to work on modern HDMI monitors takes away a lot of issues.

Bryan.

[helpful]

Also, are you using the "Boot floppy" option from the ADDFS iconbar menu to start the games? The screen shot looks like you might be directly clicking the game icon, which means ADFFS's emulation doesn't get a chance to kick in.

[guibrush]

@helpful:
ok, thanks for the warning. May I ask why RISC OS 5 ROMS are on sale explicitly for the Risc PC, and why ADFFS explicitly mention RISC OS 5 to achieve the best compatibility? I'm not questioning your warning and I believe it. I just find it contradictory with what I see (I muss say that when people find the Amiga world complicated, believe me, for a n00b in Risc PC word, is as much complicated at least ). Thanks for your help and your patience with me, I understand that my question are certainly odd...

First, I launched the games with a double click on the icon, but then I read that I have to use the boot floppy option. But unfortunately, it's the same behaviour. I only get error messages when I launch games. The main difference is that with RISC OS 4, I have a garbled screen when the game return to the desktop:




and with RISC OS 6 I have no screen at all, black screen, no signal.

[sirbod]

May I ask why RISC OS 5 ROMS are on sale explicitly for the Risc PC, and why ADFFS explicitly mention RISC OS 5 to achieve the best compatibility?

I believe you've misread what I'm saying in the requirements section of ADFFS 2.83. It's not a list of recommendation, it details the minimum requirements for various machines. For RiscPC they are:

• 32MB RAM
• RISC OS 3.x, 4.x or 5.23 Jun 9th 2016 or newer. Note that some games will not work on RISC OS 4.x due to the way it allocates screen memory in 1MB blocks. RISC OS 6 is not officially supported

That's saying the OS needs to be any version of RISC OS 3.5-4.39 or if you're using RISC OS 5, it must be a build newer than v5.23 Jan 9th. It's also saying RISC OS 4/6 aren't really suitable for games.

First, I launched the games with a double click on the icon, but then I read that I have to use the boot floppy option.

At the bottom of the ADFFS download page it states two key pieces of information you've possibly missed:

NOTE: On RISC OS 3.5+ use the PackMan distribution to receive automatic updates. Add the following URL to the PackMan sources:

Code: Select all

https://www.jaspp.org.uk/packages/release

NOTE: You must use "Boot floppy" to run supported games.

In other words, use PackMan as a source for games where possible. Using PackMan will not only keep ADFFS and the games up-to-date as I patch/update them, it will also allow games to be launched directly by double-click their icons as I've already done all the hard work to get them HD installed and patched where required.

If PackMan isn't being used, then using the JFD floppy images and "Boot floppy" from the ADFFS Filer menu to run games is the next option. There's a third option where you can create your own double-clickable games, but I won't go into that here.

As for recommendations, my personal recommendation is to use a Pi for games, it will give the most accurate experience with games all running at their correct speed and allows USB Joysticks to be used in most games. It also avoids the complications of running 50Hz games on modern monitors, particularly if connected to a UK TV as they obviously support 50Hz natively.

For purists that want to use a RiscPC for gaming, I would not recommend going beyond RISC OS 3.71. There are various fundamental changes to the OS that were made after 3.71 that make it very unsuitable for many games. Those changes have mostly not been implemented in RISC OS 5.x - but I still wouldn't recommend RO5 on a gaming RiscPC.

[guibrush]

ok, thanks for the clarifications and for your time, I appreciate

I understood the recommendation as "RISC OS 5 is better than RISC OS 4 for games", but now I understand that RISC OS 3.71 is the way to go. I will take a look if a multi-boot between 3.71 and 4.02 is possible (maybe a ROM switcher like on Amiga), I will see.

For ADFFS the games, I used packman yes:



but no game downloaded from your repo (I had to use http instead https, otherwise it doesn't work) I tried will launch. I have this error message:



it's the same with RISC OS 4.02 and 6 (I have two hdd, one with 4.02 and another one updated with 6).
What I'm doing wrong?

I only get one game (Zoom) with another message regarding the screen resolution that is not available:



And the only game that accept to launch is Wolfenstein, but only to give me a black screen (no signal). I have a 15Khz compatible monitor hooked, so I think that the problem is more that the right monitor definition are missing. But I have no idea what to do here regarding this as a newcomer.



Thanks for your help!

[guibrush]

Ok, I found that I have to launch ADFFS first, dhooo.. Make totally sense, my bad.

But my joy didn't lasted long. I still have error messages:

Simcity200


fire&ice start but hang on black screen (real black screen, not "no signal") just after that:



heimdall work! (but with a strange screen ratio)



lemmings load, but give a garbled green screen



lotus give the same green garbled screen

Speedball give this error message:



I see at boot that have have something like an extension called vprotect, I think that I saw a mention about it in an older ADFFS revision note, do I have to remove it? If yes, how?

[sirbod]

I honesty couldn't say how many of those issues are down to RO4, issues in the game packages, or bugs in ADFFS that haven't been reported yet.

ADFFS is thoroughly tested on a Pi's, but there's not a lot of testing performed on legacy platforms. I did make quite a lot of changes in 2.80 aimed at Risc PC when I noticed some unreported issues, but I've personally not tested newer builds on a Risc PC.

You could try the public beta of 2.84, which is available here, but I don't think there's many changes that affect the RiscPC.

The latest obey.zip (!ADFFS.Obey) which contains all the game scripts can be downloaded here.

Those will bring you up to the latest updates.

I see at boot that have have something like an extension called vprotect, I think that I saw a mention about it in an older ADFFS revision note, do I have to remove it? If yes, how?

You don't need to do anything with it, ADFFS includes the latest version of VProtect and updates it when you run !ADFFS. If you want to update your copy in !Boot, so it's loaded at boot, it's in !ADFFS.3rdParty

[guibrush]

ok, thanks.

I will make something: I will source a 3.71 ROM set and do the same round of test with the same games, so we will know what is related to RISC OS 4 itself.
It will take some days, as I don't have the ROMS here. But I will report back as soon I did it.

Just a small question, because I have no idea how to do it: how can I make sure that I have the right resolution available for the games? I have a 15Khz compatible monitor, and I have the feeling that some of the games are in fact running, but don't output correctly the image.

Thanks for your help!

[sirbod]

how can I make sure that I have the right resolution available for the games? I have a 15Khz compatible monitor

Press F12 at the desktop, then *Configure MonitorType with the appropriate value. 0 for a TV, 1 for a multisync.

I would try testing some of those game myself, but I'm not near my machines until next week.

[jubber]

This thread is really interesting. I've never had any luck running older software on my RiscPC, so it doesn't get a lot of use. It's using version 4.02 of RiscOS - should I downgrade it in some fashion for better compatibility?

[sirbod]

should I downgrade it in some fashion for better compatibility?

RO4 has several changes that aren't backward compatible so far as gaming goes, the main one being video memory is allocated in MB chunks. Some versions also include a version of ZLib that has a few issues. There's various other minor changes that all add up to make RO4 unsuitable for gaming.

Any game that uses hardware scrolling for example, will not look correct under RO4.

Softloading ROMs is the best solution, although the softloader doesn't let you downgrade a ROM for some idiotic reason, so sticking with RO3.71 ROMs is probably the best solution and softload later ROMs.

[jubber]

Thanks for the tip! I can see Risc OS 3.71, 3.70 and 3.60 roms on ebay, at very different prices. What was the difference between all of these?

I have a StrongArm, so possibly too far back and that won't work.

My TL866CS doesn't look up to the job of burning these at home.

[SKS1]

Thanks for the tip! I can see Risc OS 3.71, 3.70 and 3.60 roms on ebay, at very different prices. What was the difference between all of these?

I have a StrongArm, so possibly too far back and that won't work.

You need RO 3.70 or 3.71 if you have StrongARM installed in RiscPC. RO 3.71 ISTR was for the A7000.

If downgrading, your HDD content may no longer be visible if it's been formatted with a RO 4.x.

[guibrush]

interesting.

I'm still waiting to my 3.7 ROM to come, I will then test and report.

I'm happy to learn that soft booting from 3.7 to 4.x is possible, this was an open question in my mind. So I can now imagine the following scenario if RISC OS 3.7 solve the compatibility issue: fit the physical 3.7 ROM, boot with 3.7 to launch games and soft boot 6.x or 4.x for everything else-

But will the 3.7 ROM be capable to boot my RISC OS 4.x installed hard disk? It's still unclear to me what the system load at startup, as a big portion of the system is in the rom. In the Amiga world, the installed OS have to match the installed ROM in a certain way (booting OS 3.x on a 2.x ROM on Amiga isn't a good idea), how about the Risc PC ?

[sirbod]

But will the 3.7 ROM be capable to boot my RISC OS 4.x installed hard disk?

Unlikely as its probably formatted as E+, RO3.7x only supports E. If you run Partition Manager, it will tell you what the format is.

It is possible to use a small donor boot drive, that's formatted as E, that updates FileCore to support E+, before then booting off your main drive, but you're getting into pretty advanced low-level territory. I covered it in this post.

[dpsharp]

Softloading ROMs is the best solution, although the softloader doesn't let you downgrade a ROM for some idiotic reason, so sticking with RO3.71 ROMs is probably the best solution and softload later ROMs.

I agree that's a frustrating feature. Do you happen to know what checks the softloader does to determine that it won't attempt to boot an earlier version?

I'm wondering, now we have the buildable OS 3.7 source, how feasible it would be to edit the version number and any other aspects so the softloader can be persuaded to load it on machines running 4.X.

[sirbod]

I'm wondering, now we have the buildable OS 3.7 source, how feasible it would be to edit the version number and any other aspects so the softloader can be persuaded to load it on machines running 4.X.

It would be more useful to remove the check in the softloader. The source for it might be on ROOL - I've not checked.

[dpsharp]

It would be more useful to remove the check in the softloader. The source for it might be on ROOL - I've not checked.

Yes it would. I'd not realised it was a standalone tool rather than being built into the OS.

Looks like the source is here https://gitlab.riscosopen.org/RiscOS/Ut ... c/softload

I can't see any obvious ROM image version regression check in head or the oldest version; do you recall what the behaviour is if you try and load older versions of the OS? I'll have a play with it the softloader at some point and see if I can reproduce it.

[ccawley2011]

The menu for the softloader is in a separate repository and can be found here: https://gitlab.riscosopen.org/RiscOS/Ut ... Prompt,fd1

The -all parameter can be used to list all ROMs, not just the ones that are newer. I normally have that option enabled to allow unloading a previously loaded ROM without turning the machine off and it works fine, but I haven't tried using it to downgrade from a previous ROM.