Acorn Archimedes Software Preservation

[deicidal]

Originally Posted by breach

Oh! I'd have expected them to have had labels is some kind of info at least.

Nope just the date, will try look into getting them imaged tonight if i can and see if i get anywhere. Thanks for the link.

Any ideas where you can get video cables from so i can display the unit i have on my TV.

Also are there keyboard combinations that you can use instead of the mouse as i dont have one, or for that matter where you could get one of those as well.

[deicidal]

I don't suppose anyone knows if you can image the archimedes disks with an amiga?

[prowler]

No, but if you can't get all the bits you need to do it on your Archimedes, then you can do it on a PC running the DOS utility 'Arcimg'.

http://eab.abime.net/showpost.php?p=458437&postcount=91

[gizmomelb]

Originally Posted by deicidal

I don't suppose anyone knows if you can image the archimedes disks with an amiga?

I used to nibble copy Arc discs for my mates using my A500, seemed to work ok for them with copy protected stuff.

[deicidal]

Well I have ordered a usb floppy drive so the moment that gets here from china i will image them

[MarkYoungIW]

Originally Posted by Jon Abbott

Does anyone have the ability to create APD's? To ensure the density detection works on APD's, I really need an example of SD and QD discs (1.6MB). They don't need to be protected, but an APD and matching ADF would be helpful so I can compare them side by side.

I've found a grand total of 35 ADP's and have successfully decoded and mounted 32 of them. Trouble is, all the APD's are DD discs, so my assumptions about the sync marks may or may not be applicable to SD / QD discs.

Did any software even come out on SD? All the ADF/APD's I've seen so far are DD or QD. Zarch looks like it could be an odd exception as side 0 is DD and side 1 is possibly SD - not sure if that's down to the protection or not though.

Anyhow, now I've reverse engineered the APD structure, I'm looking into taking over ADFS to present mounted images as ADFS:0

Just had a look at some old messages, and Tom had told me that Zarch and Magic Pockets were the only games he was aware of that had single density sectors as well as double density sectors.

I can image some discs if you need, as have an A1200 sitting here ready for the job. Let me know.

Originally Posted by Jon Abbott

Anything hard coded to ADFS:0 will fail, if it just wants <FS>:0 you should be fine.



Multidisc games may be an issue, if you no longer have access to the WIMP to change the disc.



What's the game? Can it be installed to the HD?

What I was sort of thinking is you are making something fairly similar to WHDLoad on the Amiga which is really nice in the fact that you can store everything in the same format (rather than having some ADF's/ADP's and some HD installs etc).

With the multidisc games I have tried none of them give you access back to the wimp to enable you to change the adf. I didn't know if perhaps looking at adding a small loading script for multidisc games was a possibility later on.

[Jon Abbott]

Originally Posted by MarkYoungIW

With the multidisc games I have tried none of them give you access back to the wimp to enable you to change the adf. I didn't know if perhaps looking at adding a small loading script for multidisc games was a possibility later on.

One possible way around this is to look for keyboard combinations and have it automatically load the images associated. ie Ctrl-Alt-Shift-F1 for disc1, Ctrl-Atl-Shift-F2 for disc2. Haven't got that far yet though.

I've analysed all 32 protected APD images in detail now. Only 25 actually use protection, of those there are 18 distinct methods being used, ranging from sector within sector to invalid ID's and alternative sector sizes.

In essence I need to write a 1772 FDC emulator and feed the output into ADFS. That isn't possible though, without patching or rewriting sections of ADFS - which isn't really a viable option due to the vast number of versions out there. The alternative, which I'm trying, is to front ADFS and pass-through calls where appropriate.

I also need to expand the DiscOp functions in ADFFS, as I didn't bother coding DiscOp 3/4 (read/write track) - they weren't required for ADF images. Some of the protection methods however rely on DiscOp 3, to read sector within sector and invalid sector ID's.

Although Zarch and MagicPockets have SD track data in the APD file, it looks like DD tracks that just happen to verify when read as SD. Zarch certainly seems to load with DD track data only, as its protection is to check for alternative sized sectors on the disk. I suspect MagicPockets is the same, as it has a blank track and alternative sized sectors.

If anyone is aware of more protected discs, please let me know so I can try to source the originals to analyse them. One's I'm aware of are:

Cycloids
Darkwood
Drop Ship
The Dungeon
Fire & Ice
FTT
Gods
Gribbly's Day Out
The Last Ninja
Magic Pockets
Nevryon
Pandora's Box
Populous
Powerband
Repton 4
Sensible Soccer
StarFighter 3000
The Wimp Game
Wolfenstein
World Class Leaderboard
Zarch.

Although APD's are available for the following, they do not use disc protection - they use other methods, such as code wheels, manuals etc:

Premier Manager
Repton 3
Stunt Racer 2000

Seems, like an awful lot of coding for so few discs!

[MarkYoungIW]

There can be lots more. I have a number not there. Leave it with me, I'll eMail you some. Tom's APD seems to work for all protected discs, and there are many protected discs for the Arc. I will get on that today.

[breach]

According to this thread http://www.iconbar.com/forums/viewth...d=11868&page=1 Inferno and Quark use copy protection.

I actually have both original games but I don't know how to make APD format files.

APD seems to be a bit too closed a format for useful preservation.

[MarkYoungIW]

I dont think it is intentionally closed and I am sure it will soon be fully documented (also Jon sounds like he has pretty much reversed it now already!!)

With regards to making an apd its fairly simple. It involves Rawread on the Amiga like this and a windows app Tom made called getapd.exe

There were a lot of games that were protected in many ways, I am sure not all of these require apd, but some definately do.

Hope this helps.

[Jon Abbott]

Originally Posted by breach

APD seems to be a bit too closed a format for useful preservation.

It's actually very basic, 160 raw MFM tracks, with FM SD and MFM QD tracks where those densities verify. From what I've seen so far, it's more than sufficient for preservation of all discs.

[breach]

Originally Posted by MarkYoungIW

With regards to making an apd its fairly simple. It involves Rawread on the Amiga like this and a windows app Tom made called getapd.exe

Is there any alternative to the Amiga & Rawread? I don't have an Amiga. Actually the only system I have with a floppy drive is the Acorn.

Originally Posted by Jon Abbott

It's actually very basic, 160 raw MFM tracks, with FM SD and MFM QD tracks where those densities verify. From what I've seen so far, it's more than sufficient for preservation of all discs.

OK, well that's good to know.

[Jon Abbott]

I won't post off topic updates here, but I'm making good progress with ADFFS, APD support is getting there and I now have control of ADFS::0

See the following thread for further updates:
http://riscos.me.uk/forums/viewthrea...threadid=11846

I've heard nothing from SPS after raising a ticket a few weeks ago, so no progress on IPF support.

[MarkYoungIW]

Hi Jon,
Many thanks for the updates. I think most people would agree with me that ADFFS will be as important to Acorn as WHDLoad has been to the Amiga, if not more so!

Really pleased to hear you have got ADFS::0 that could have been a big problem with some images.

Thank you for your work for the Acorn scene, with this for the real hardware and Tom's Arculator for those times we can't be bothered to get the Arc out of the loft, I think its fair to say it makes all the disc images, so much more meaningful!!

[Jon Abbott]

I have a few bugs to iron out, but have over half the APD's now working under ADFFS. Mark - I'll send you an updated beta later, it's still RO 3.5+ only. If that's an issue let me know and I'll spend some time getting backward compatibility fixed.

Anyhow, whilst analysing the various protection methods used, it dawned on me that I could probably automate what I'm doing, to allow floppies to be captured on the Arc. Essentially what I'm doing is recording all the disc access and responses from ADFS and then replaying them in ADFFS, to confirm I'm returning the correct data and errors.

However, there's no reason why this couldn't be automated and possibly with a little user input for the more complex methods, the disc captured into a working image. The bulk of the disc can be read sector by sector, based on the core Disc Rec - the other Disc Recs for the protection areas are all captured by running the game and recording it's disc access. It's then a matter of filling in the gaps in the protection tracks, noting any unformatted tracks / sectors with CRC errors in the data or sector ID - this may not be required, it obviously depends on how the protection is performed. If all the protection checking is done up front, it should be reliable. Sector within sector may need some hand holding, where DiscOp 3 (read track) is used (Fire & Ice for example).

Just a thought, obviously I want to get ADFFS working with APD's reliably first before thinking about extending ADFFS, to add reconstruction.

It will however probably need yet another file format, as IPF / APD are floppy image based, rather than data image based. I suppose it's possible to convert the data back into MFM and reconstruct an IPF / APD - but it won't be a 100% accurate representation as they are currently.

[breach]

Wait, wait, wait! This all sounds spectacularly awesome, even though I'm not completely sure I understand it!

Are you saying you could release a utility that would be able to create APDs on an Acorn? But that it would have to go through an intermediate format first?

[Jon Abbott]

Originally Posted by breach

Are you saying you could release a utility that would be able to create APDs on an Acorn? But that it would have to go through an intermediate format first?

That is exactly what I'm saying.

[deicidal]

Originally Posted by deicidal

Well I have ordered a usb floppy drive so the moment that gets here from china i will image them

Didnt think that one through, the disk imaging software doesn't work with usb drives.

[Jon Abbott]

There's an early beta of ADFFS with APD support available, head over to the Icon Bar thread to see the caveats before downloading though.

http://riscos.me.uk/forums/viewthrea...&page=3#119972

EDIT: 1.21 is available, which is a stable release supporting virtually all APD's: http://adffs.filecore.net

[Jon Abbott]

Now that APD support is nearly complete, I'm looking at expanding ADFFS into a complete retro gaming solution, along the lines of MAME/MAMEUI.

Some of you may be able to help out, with instructions, scans, screenshots etc. Take a look at the "help wanted" section on the Icon Bar thread and let me know your thoughts/ideas:

http://riscos.me.uk/forums/viewthrea...threadid=11846