Can Amiga read/write to Atari ST floppy disks?

[Blitter]

I have just acquired an Atari ST, and need some files putting onto floppies to run on it. I don't have a PC, or know anyone who still has a floppied-up PC.

Can I transfer files from my Mac to my Amiga 1200 (with a PCMCIA CF Card Reader), and then from the Amiga save them onto Atari formatted floppies?

What program do I need on the Amiga to do this if so?

[puppypc]

If I'm reading this thread right: http://www.amiga.org/forums/showthread.php?t=66269

then you should be able to read and write to an Atari-compatible disk using CrossDOS which you can activate by running CrossDOSFileSystem, located in your L folder

[idrougge]

You activate CrossDOS by running moving PC0 from SYS:Storage/Dosdrivers to DEVSosdrivers.

[jizmo]

If you just copy the disk images or system files to a DD PC format disk, CrossDos or a similar program will do.

Be advised though that most of the Atari disks use extra sectors and the disk images - .msa for example - need to be written on a disk using a special program, and I'm skeptical that one actually exists for the Amiga.

If you have enough memory on the Atari side you can split the disk images to floppies, join them to Atari RAM disk (available with 3rd party programs) and rewrite to a floppy on the Atari disk drive.

All in all, you'd probably be best off with some modern Atari CF/SD HDD solution.

[idrougge]

You can write .ST and .MSA on Amiga. Use XadUnDisk from the XAD package and http://aminet.net/package/dev/src/xad_MSA plugin.

[Nobby_UK]

I did it in the past...

[Armitage]

Originally Posted by idrougge

You can write .ST and .MSA on Amiga. Use XadUnDisk from the XAD package and http://aminet.net/package/dev/src/xad_MSA plugin.

I tried to do this exact thing today. I installed xadmaster and xad_MSA, enabled CrossDOS and pc0. Formatted a disk on my ST, brought it over to the Amiga and it was recognized and had the correct name and everything. I ran XadUnDisk filename.msa pc0: and it successfully completed writing the image to disk. When I load the disk on my ST, it either bombs immediately or the machine fails to boot entirely. I tried adding the DISKIMAGE option but that didn't work either. Am I doing something wrong?

[AmigaHope]

Originally Posted by Armitage

I tried to do this exact thing today. I installed xadmaster and xad_MSA, enabled CrossDOS and pc0. Formatted a disk on my ST, brought it over to the Amiga and it was recognized and had the correct name and everything. I ran XadUnDisk filename.msa pc0: and it successfully completed writing the image to disk. When I load the disk on my ST, it either bombs immediately or the machine fails to boot entirely. I tried adding the DISKIMAGE option but that didn't work either. Am I doing something wrong?

What you were doing initially was just dumping the extracted files to a FAT disk -- it won't be bootable because you're not writing the boot sector. If you boot to GEM/TOS on the ST you should still be able to see the files on the disk just fine when you insert it.

If you want to write a bootable ST disk on the Amiga you need to actually write the raw disk image to the device directly using a disk writing utility, not to the pc0: filesystem. I don't know if xadundisk tries to do this with the DISKIMAGE option (rather than dumping a file with the disk image) but if it does it's probably tuned to Amiga floppies. If you can get xadundisk to write a raw floppy image to a file, tsgui should probably be able to dump said file to the floppy.

[Armitage]

Originally Posted by AmigaHope

What you were doing initially was just dumping the extracted files to a FAT disk -- it won't be bootable because you're not writing the boot sector. If you boot to GEM/TOS on the ST you should still be able to see the files on the disk just fine when you insert it.

If you want to write a bootable ST disk on the Amiga you need to actually write the raw disk image to the device directly using a disk writing utility, not to the pc0: filesystem. I don't know if xadundisk tries to do this with the DISKIMAGE option (rather than dumping a file with the disk image) but if it does it's probably tuned to Amiga floppies. If you can get xadundisk to write a raw floppy image to a file, tsgui should probably be able to dump said file to the floppy.

Ah good info, thanks! I will try a few more things and see if I can get anything to write a bootable disk from the msa image.

[Retro1234]

qI did write .ST image to disk ok using PC-task but you would think there was a easier method - looks like XadUnDisk can do it if idrougge says so.

[th4t1guy]

Would disk-analyse also work? It says it has read/write support for HFE formats, so you could try converting images to HFE.
https://github.com/keirf/Disk-Utilities

[AmigaHope]

Originally Posted by Armitage

Ah good info, thanks! I will try a few more things and see if I can get anything to write a bootable disk from the msa image.

Also be aware that your .msa will not be writable to the pc0: device if it uses a custom track layout. pc0: is set up as a standard 720k FAT floppy. You'll have to create a new device configuration that has the same track layout as the .msa file. Mostly this means changing HighCyl=79 value in the pc0 DosDrivers file to 80/81/82 to match however many tracks are on the custom floppy.

This also counts if it's a single-sided 360k disk image (Atari was so effing stupid to go with a single-sided drive in 1985) -- you'll have to create a single-sided device configuration to write to then. Editing the pc0 DosDrivers file to include "Surfaces=1" should be sufficient for this.

In fact single-sided floppies on Atari ST were so common, that should be the first thing that you check.

Remember you can't edit the DosDriver mountfile live -- if you edit it you have to dismount it (dicey) or better yet reboot. I recommend creating separate mountfiles for each track configuration you create and only having them enabled one at a time.

[Armitage]

Great stuff there! I have been trying to write a single sided msa image to disk up till this point. I will try creating single- and double-sided driver files and give those a shot.

[AmigaHope]

Originally Posted by Armitage

Great stuff there! I have been trying to write a single sided msa image to disk up till this point. I will try creating single- and double-sided driver files and give those a shot.

Try to see if list/info in xadundisk tells you about the geometry of the .msa file.

Totally standard TOS/GEM single-sided format disk is:

LowCyl = 0
HighCyl = 79
BlocksPerTrack = 9
Surfaces = 1

Custom formats used by games (and adventurous users) push sector count (BlocksPerTrack) to 10 or 11, and highest track (HighCyl) as 80, 81, 82. The ability of your drive and software to write those formats may vary.

[Armitage]

Ahh good call with getting image geometry info. I had created a new DosDriver for a single sided ST disk, but the resulting disk was still not working correctly. It didn't occur to me there might be a custom disk geometry at work there.

[Foebane]

This may be slightly OT, but I used CrossDOS for reading MS-DOS disks rather than ST ones. I was in a university computer course in the mid-1990s that, of course, focused on PCs for the coursework, and of course, I still had my A1200 when others I knew had traded in their Amigas for PCs for the coursework.

I had no issue with moving the files back and forth, but there was one ridiculous difference between Amiga and PC that caused a lot of problems: the PC's insistence on using TWO ASCII characters for each line, namely Carriage Return and Line Feed, whereas the Amiga only used ONE. Basically, I didn't know how else to remove the blank lines between each line of program code I wrote, so I spent a good few minutes, several times, deleting the excess characters. Real pain in the proverbial ASS.

[AmigaHope]

Originally Posted by Foebane

This may be slightly OT, but I used CrossDOS for reading MS-DOS disks rather than ST ones. I was in a university computer course in the mid-1990s that, of course, focused on PCs for the coursework, and of course, I still had my A1200 when others I knew had traded in their Amigas for PCs for the coursework.

I had no issue with moving the files back and forth, but there was one ridiculous difference between Amiga and PC that caused a lot of problems: the PC's insistence on using TWO ASCII characters for each line, namely Carriage Return and Line Feed, whereas the Amiga only used ONE. Basically, I didn't know how else to remove the blank lines between each line of program code I wrote, so I spent a good few minutes, several times, deleting the excess characters. Real pain in the proverbial ASS.

Definitely OT -- but there were tons of tools for dealing with precisely this issue, or if you were working with stock workbench you could use the edit command with a "WITH" script to do this. =)

[sparhawk]

Originally Posted by Blitter

I have just acquired an Atari ST, and need some files putting onto floppies to run on it. I don't have a PC, or know anyone who still has a floppied-up PC.

An USB floppy drive costs < 20€ at Amazon. Don't know if such tasks can be done with an USB drive though. I know that the PC can read Amiga disks with a special trick, but that would require a real IDE controller.

[AmigaHope]

Originally Posted by Armitage

Ahh good call with getting image geometry info. I had created a new DosDriver for a single sided ST disk, but the resulting disk was still not working correctly. It didn't occur to me there might be a custom disk geometry at work there.

Also, just to explore another option, what sort of Atari ST setup do you have? Do you have a second drive, or 1 meg of memory? You could copy the .msa to a regular FAT floppy that your ST can read from TOS/GEM, and use that file on a second floppy drive or a just-large-enough ram disk on the ST you could then use the native ST MSA tools to write out the image to disk directly on the ST.

Kind of like in this video, only just transferring everything via the floppy to the ram disk rather than the null modem cable:

[ Show youtube player ]

[Armitage]

Originally Posted by AmigaHope

Also, just to explore another option, what sort of Atari ST setup do you have? Do you have a second drive, or 1 meg of memory? You could copy the .msa to a regular FAT floppy that your ST can read from TOS/GEM, and use that file on a second floppy drive or a just-large-enough ram disk on the ST you could then use the native ST MSA tools to write out the image to disk directly on the ST.

Update: Using the info/list option to XadUnDisk, I discovered the image I was trying to write uses 10 blocks/track instead of the default 9 so I adjusted my DosDriver accordingly and formatted the disk (on the Amiga). Still isn't working, but have a few more things to try.


It's a 1040STf, single drive w/1MB. I don't have any of the original system software or any way to transfer it yet. Does the GEM desktop in ROM know how to handle the MSA files or is that additional software?