MAME: Archimedes

[Pernod]

It's time to give the Archimedes some attention in MAME, and as I've not really used one there'll be lots of questions.

At the moment the Archimedes emulation is okay'ish, but there's lots of improvements to be made, especially with hard drives and expansion podules.

I'm currently looking at the A4, which has a 5th column extension ROM to handle battery management. I see the ROM recognised with *podules but no sign of the Battery Manager in *modules, I also don't see !BatMgr in Applications. I know the BMU is on the I2C bus but am not seeing any I2C data directed at anything but the PCF8583.

Anyone know how to activate the Battery Manager? Is there maybe a register somewhere that tells RISCOS that a battery is fitted?

[robcfg]

I'll try to pick up my A4 from my storage place today and look for it.

[robcfg]

Ok, I found my A4 at the storage place, which is quite a remarkable achievement

The !BatMgr app is on the Apps icon on the left of the icon bar.

It does add a battery percentage bar on the right of the icon bar. Mine shows a question mark as I removed the battery for safety concerns.

The app icon itself contains a !sprites file and a !run file with the following content:

Code: Select all

RMEnsure BatMgr 0.00 Error 0 BatMgr module not loaded
BatMgr_AddIcon

I assume the referenced BatMgr module should be contained in the extra rom of the A4.

The icon appears at boot, so I don't know why it's not getting activated on your end.

Please tell me if you need me to do more tests.

Cheers,
Rob

Edit:

I found this interesting text on the extra rom:

[Pernod]

I assume the referenced BatMgr module should be contained in the extra rom of the A4.

The icon appears at boot, so I don't know why it's not getting activated on your end.

Thanks, I can only assume it's disabling itself due to not finding the battery management unit (BMU).

[Pernod]

The Archimedes expansion bus has peripheral select lines 4, 6, 7. I believe the majority of expansion podules respond to peripheral select 4 (Ps<4>), correct?

Are there any known podules that are enabled by Ps<6> and Ps<7>?

[Pernod]

Here's a simple question ... if I reset the CMOS how many floppy drives does RISC OS default to? Does it detect the number of floppy drives connected, or always default to 2?

If it does set floppies to the correct number then what is it actually checking?

[IanJeffray]

Here's a simple question ... if I reset the CMOS how many floppy drives does RISC OS default to? Does it detect the number of floppy drives connected, or always default to 2?

For machines which have the high density 71x controllers (rather than 1770) it will do a drive detect and show zero if it doesn't find a drive. I'm not sure if it'll ever automatically show more than 1 in such cases - such machines would be quite rare though, so I wouldn't be surprised if it doesn't.

For 1770-controller machines (Axxx and A3000), it always defaults to 1 and doesn't (can't?) do detection.

[steve3000]

Here's a simple question ... if I reset the CMOS how many floppy drives does RISC OS default to? Does it detect the number of floppy drives connected, or always default to 2?

For machines which have the high density 71x controllers (rather than 1770) it will do a drive detect and show zero if it doesn't find a drive. I'm not sure if it'll ever automatically show more than 1 in such cases - such machines would be quite rare though, so I wouldn't be surprised if it doesn't.

It does show >1 if connected. I have two internal 3.5” and one external 5.25” on my A5000 and all three are auto-detected. If I unplug the external drive from the cable, only two drives appear on startup. I think the detection at startup is by RISC OS moving each drive head independently out one track then back to track 0 - the detection of the drive by opening/closing the track 0 signal? Can’t see why this wouldn’t work with the 1772, but Acorn only implemented the startup check in the 71x driver…

[IanJeffray]

It does show >1 if connected.

Does it auto-update the configure setting, then? Does it just IGNORE the configure setting? I kind of expected to have to configure >= the number of drives, then let RISC OS go "nup" and hide the missing ones. Interesting.

[steve3000]

It does show >1 if connected.

Does it auto-update the configure setting, then? Does it just IGNORE the configure setting? I kind of expected to have to configure >= the number of drives, then let RISC OS go "nup" and hide the missing ones. Interesting.

I think it ignores, but I could be wrong. Will check and report back at the weekend.

[IanJeffray]

I think it ignores, but I could be wrong. Will check and report back at the weekend.

Interesting. Floppies are always a pain point for me. I never did get this funky chicken working...

I think it's essentially just two independent floppy mech's bolted together bahind a single faceplate. Primary input connector is ye olde 5.25" style edge connector. Never got any Acorn machine to even activate either part.

[daveejhitchins]

Interesting. Floppies are always a pain point for me. I never did get this funky chicken working...

I think it's essentially just two independent floppy mech's bolted together behind a single faceplate. Primary input connector is ye olde 5.25" style edge connector. Never got any Acorn machine to even activate either part.

Wow . . . That's an interesting drive - not seen one before - who's the maker and model number?

Dave H.

[IanJeffray]

Wow . . . That's an interesting drive - not seen one before - who's the maker and model number?

It's a TEAC FD-155GF.

EDIT: That model number is probably just the 5.25" part. The whole assembly may be known as the TEAC FD-505. There are very few markings on it.

[daveejhitchins]

Wow . . . That's an interesting drive - not seen one before - who's the maker and model number?

It's a TEAC FD-155GF.

EDIT: That model number is probably just the 5.25" part. The whole assembly may be known as the TEAC FD-505. There are very few markings on it.

Thanks, Ian . . . I'll have a look around.

Dave H.

[Pernod]

I don't have any floppy drives, but I do now have !BatMgr:

[Pernod]

This may be a wild idea ...

There's lots of Archimedes software out there that's archived as .arc files, ie. needs extracting with ArcFS or whatever. This is especially common for podule drivers, where the .arc is the contents of the accompanying floppy. Getting these .arc files into MAME is a bit of a problem as there's no easy way of transferring the file to the emulated machine, whereas in Arculator you can access them through hostfs. At the moment I'm having to transfer the files in Arculator from hostfs to a hard drive image .hdf, which I can then mount in MAME.

So I'm thinking why not mount an .arc file as a floppy image by reconstructing an 800K adf containing the single .arc file. We have Disk Image Manager and Beeb Image that already implement the same principal, so why not make .arc files easier to access in MAME by being able to mount them as a floppy.

Good idea, useful ,any potential issues?

[steve3000]

So I'm thinking why not mount an .arc file as a floppy image by reconstructing an 800K adf containing the single .arc file. We have Disk Image Manager and Beeb Image that already implement the same principal, so why not make .arc files easier to access in MAME by being able to mount them as a floppy.

Good idea, useful ,any potential issues?

So you're suggesting having something like a blank 800kb (or 1600kb) adf image, and a short script to pop the .arc file of your choosing into the adf image?

Sounds like a great idea for MAME and possibly other emulators. I'm sure this should be straight forward for those with appropriate knowledge of ADFS E/F disc format.

You'd still be limited by the disc image maximum 1600kb, so no chance of squeezing a 2mb .arc file. You'll also need !ArcFS and/or !SparkFS handy on another adf or your MAME HDD image, to open the .arc file. But overall would certainly make life easier getting files into MAME.

[Pernod]

So you're suggesting having something like a blank 800kb (or 1600kb) adf image, and a short script to pop the .arc file of your choosing into the adf image?

Correct.

You'd still be limited by the disc image maximum 1600kb, so no chance of squeezing a 2mb .arc file. You'll also need !ArcFS and/or !SparkFS handy on another adf or your MAME HDD image, to open the .arc file. But overall would certainly make life easier getting files into MAME.

Are there many .arc files out there that won't fit on a floppy? How would you get a 2MB .arc file onto real hardware if you can't transfer it via floppy?

[steve3000]

Are there many .arc files out there that won't fit on a floppy? How would you get a 2MB .arc file onto real hardware if you can't transfer it via floppy?

I use network, ZIP discs and CD-ROMs...In that order.

But it depends on where ''out there" is and it's not just .arc files which this would help... I suspect most casual emulator users would just want games discs and ADFFS from the JASPP site. The .jfd disc images here will all be disc size or smaller, and although most recent zipped versions of ADFFS would need a 1.6m disc image, ADFFS 2.63 fits in less than 800kb.

I guess ideally what would be nice would be a .hdf file browser on the PC side, to allow you to modify a RISC OS HDD image directly.

[Pernod]

I guess ideally what would be nice would be a .hdf file browser on the PC side, to allow you to modify a RISC OS HDD image directly.

You should be able to do that with Disk Image Manager.

[steve3000]

I guess ideally what would be nice would be a .hdf file browser on the PC side, to allow you to modify a RISC OS HDD image directly.

You should be able to do that with Disk Image Manager.

Well well...indeed you can! And I installed this ago, but only thought to use it for adf disc images.

[SteveBagley]

This may be a wild idea ...

I've got a wilder one

So I'm thinking why not mount an .arc file as a floppy image by reconstructing an 800K adf containing the single .arc file. We have Disk Image Manager and Beeb Image that already implement the same principal, so why not make .arc files easier to access in MAME by being able to mount them as a floppy.

I don't know much (anything!) about how MAME works, but is there a way you could find the block of memory containing the RAMFS, RAM disk and poke the bytes for the .arc file into the RAM disk?

Or create ROM images and emulate the ROM podule?

Steve

[Pernod]

I don't know much (anything!) about how MAME works, but is there a way you could find the block of memory containing the RAMFS, RAM disk and poke the bytes for the .arc file into the RAM disk?

No, that would be far too complex, and would need to assume that a RAM disk is already configured and has sufficient space for the .arc.

Or create ROM images and emulate the ROM podule?

Not sure what you mean by create ROM images, but the Acorn AKA05 ROM podule is already emulated.

[SteveBagley]

No, that would be far too complex, and would need to assume that a RAM disk is already configured and has sufficient space for the .arc.

I thought it might be…

Or create ROM images and emulate the ROM podule?

Not sure what you mean by create ROM images, but the Acorn AKA05 ROM podule is already emulated.

The ROM podule supports a ROM file system, so you could create rom images that contain the archive, which might be simpler than building an ADFS disc structure (you'd be limited to 1MB though).

Steve

[IanJeffray]

I never did get this funky chicken working...
IMG_E6228.JPG
I think it's essentially just two independent floppy mech's bolted together bahind a single faceplate. Primary input connector is ye olde 5.25" style edge connector. Never got any Acorn machine to even activate either part.

(Weird thread to dig up about this but anyway...)

FWIW I did just get both parts of this drive working with an A310
It appears as drives :1 and :2 - which is exactly what its documentation says.
There may be some mis-alignment as the 3.5" didn't want to read back a disc it formatted, but read others perfectly well.
The 5.25" formatted and read a Beeb floppy using !DFS too