ADFFS 2.31 beta

[JonAbbott]

Fixes to bundled modules to get Magic Pockets working, thanks go to Martin Bazley for highlighting the issue.

NOTE: You must ensure fake_vsync_isr=1 is uncommented in your config.txt file on the Pi. If you see a blank screen, try setting the monitor to Auto. Also ensure the ARM is configured as ARMv5


Changes since 2.30

• TrackerMod updated to 5.02 to fix music in Magic Pockets
• ADFS shim module updated to fix Magic Pockets
• DTT shim module updated to make it 32bit compliant
• JoyMod module added, 32bit compliant on IOMD

Known issues

• Doesn't support the protection used by Chequered Flag (non-RO3 version), Fine Racer and KerBang! (they talk directly to the FDC via IOC)
• Shelling out of the desktop (Ctrl-Shift-F12 twice) hangs if an HD floppy is mounted on RO3.5+
• adfs:format doesn't work whilst ADFFS is loaded
• Although Caverns runs fine under VIDC translation on the A7000, on a RPC the scrolling is broken; with no VRAM, its completely broken. There's also an issue with the ship only appearing on the bottom half of the screen, although this is resolved with the boot script included with ADFFS.
• Will not work on a RISC OS 3.1x machine with more than 13mb allocated to application space. To workaround increase another area until Applications (free) is below 13mb and ensure it never goes above it whilst ADFFS is loaded
• Has not been tested on RO5.21 alpha builds of after 4th Dec 13
• Does not currently work on RO5.x IOMD
• RO4/SA some games don't display (eg Zarch)
• No 26-bit module support yet
• Currently requires 30mb of free memory to work on a StrongARM machine
• Does not work on OMAP3/4, untested on Iyonix
• Games that update the display on event 4 currently flicker (eg Chuck Rock, James Pond)
• Sometimes reports "Broken directory" after loading (exiting and reloading is a temporary fix)

Games that are made StrongARM/Pi compatible with this
Conqueror
Humanoids (of Humanoids & Robotix)
Jet Fighter
The Krisalis Collection: Revelation! [BUZZ version]
The Krisalis Collection: Terramex
Magic Pockets
Pac-mania
Pac-mania [Learning Curve version]
Revelation!
Revelation! [BUZZ version]
Revolver
Rise in Crime
Terramex
Zarch

NOTE: The "Boot floppy" scripts have been updated for many games, so ensure you have !SparkFS or similar loaded before using "Boot floppy".
If you've contributed one of the unreleased titles and have the JFD floppy image, it should work provided you have !SparkFS or similar loaded. Alternatively, extract the relevant Obey file from !ADFFS.obey and launch manually.


Please provide feedback, let us know if it's working or if you see any issues.

[grannyg]

I tried Magic Pockets from here but I just get a blank screen. Pressing return and the normal mouse pointer appears. The only way out is to press ctrl-break.

Whereas the version of Magic Pockets I had already works fine. I think the jfd version from here may be corrupted in some way.

On loading adffs for the first time and clicking on the filer icon without first double-cliciking a 'floppy' file causes a hang. Ctrl-break is the only way out. Ocassionally I get an error with random characters.

There also seems to be noticable tearing in Magic Pockets and now I think about it in Pacmania as well, although not as obvious. There is a slight wobble when the screen scrolls.

[JonAbbott]

I'll check both issues

[JonAbbott]

I tried Magic Pockets from here but I just get a blank screen. Pressing return and the normal mouse pointer appears. The only way out is to press ctrl-break.

Whereas the version of Magic Pockets I had already works fine. I think the jfd version from here may be corrupted in some way.

It was indeed corrupt, both the full archive and the individual disc image. I've updated both and confirmed they're now okay...I'm going to check the rest now.

Just goes to show how many people are downloading and using them

EDIT: Every file was corrupt - how this hasn't been spotted until now I don't know. I've reuploaded all of them, so if you've previously downloaded any, I'd advise redownloading them.

[richw]

Jon, please don't be disheartened. I am very excited by the entire project, and think the work to date is phenomenal. I have been tracking progress, but I do not even have appropriate hardware etc. I was toying with finding an old Arc, but the way things are panning out, maybe I should get a Pi? I don't know how you find the time - think I would do well to spend 40 mins each evening on it!

I suspect others are hanging back until there are less geeky requirements.

One thing I see as frustrating now is the availability of titles. Many are not available legally, and some that are are on the wrong media/format with 'interesting' pricing. Maybe this just takes time - I am stunned you've got anything for free download!

[JonAbbott]

On loading adffs for the first time and clicking on the filer icon without first double-cliciking a 'floppy' file causes a hang. Ctrl-break is the only way out. Ocassionally I get an error with random characters.

I'm seeing this also, I expect it's a bug in the ADFS shim module as it's 32-bit specific. Will investigate and resolve.

There also seems to be noticable tearing in Magic Pockets and now I think about it in Pacmania as well, although not as obvious. There is a slight wobble when the screen scrolls.

It's the frame pacing causing the tearing, I've been looking at ways to resolve it over the past couple of days.

At the moment, from the games perspective VSync is triggered at 50Hz so the game and music play at the correct rate. From the blitters perspective VSync is going at the monitors rate (currently this is fixed based on EDID data). That's fine for games that use frame swapping, but doesn't work so well on games that use a single frame and update the screen on VSync. In this situation, the blitter will be copying the frame mid-update.

There are two solutions I'm looking at:

1. Use a second frame buffer on the GPU, so the blit is done off-screen at 50Hz and frame swap the GPU at the monitor VSync rate
2. When ADFForceVSync is set to 1, turn off the 50Hz VSync and leave it running at the monitor rate. This is okay, as no games run at 100Hz.

Method 1 seems the best option, as it leaves the game abstracted from the hardware and is the solution I'm going to try first. Method 2 has major drawbacks, in that the music in Pac-mania will be wrong and most games will play too quickly. The problem is that every Pi could be running at a different rate, as currently there's no control over the refresh rate, its fixed by the Pi firmware.

I should probably add, I've spoken to Jeffrey Lee about the situation with EDID and if we can get 50Hz support added - it would seem it's possible, so may be added at some point in the future.

[grannyg]

Thanks. The version of Magic Pockets from here now works too. Also the map in conqueror now works.

My monitor can do 50Hz refresh even though it doesn't officially support it. I tried changing config.txt to ignore EDID and forcing a 50Hz screen mode. It didn't seem to make any difference to Magic Pockets or Pacmania. I take it there's more to it than that.

[JonAbbott]

RISC OS currently has no control over the refresh rate, its derived from the EDID data the monitor supplies to the Pi firmware. This will be resolved in a later build of RISC OS, currently we're stuck at whatever resolution and refresh rate the Pi firmware decides to use - in most cases this will be the native resolution of the monitor @ 60 Hz.

[grannyg]

The GPU on my RPi is currently outputting a screen mode with a 50Hz refresh. I overrode the defaults in config.txt. This had no effect on any of the games I tried. Does ADFFS assume a 60Hz refresh also? I was just wondering why it didn't appear to make any difference.

[JonAbbott]

The GPU on my RPi is currently outputting a screen mode with a 50Hz refresh. I overrode the defaults in config.txt. This had no effect on any of the games I tried. Does ADFFS assume a 60Hz refresh also? I was just wondering why it didn't appear to make any difference.

The game refresh rate is abstracted from the hardware and runs at the games correct FPS, so 50Hz for Pac-mania or 25Hz for Zarch for example. The GPU frame blit however is triggered by VSync, so in your case will be 50Hz.

The issue you're seeing is due to the two being out of sync, hence why I need to implement frame swapping on the GPU so you don't notice it.

Could you please post the config.txt settings you used.