Is there detailed file system documentation available for the standard and common custom DOSes?

[Zolaerla]

As the subject says. I've been trying (and failing) to find detailed information on the actual file systems used by various DOSes on the Atari. I have only found full details for the old DOS 2.0 720 sector SD format. I already know FAT12/16 since I coded for MS-DOS back in the day, but that would have compatibility options with the Atari OS, at least for booting.

 

What about the other DOSes like DOS 3, DOS 2.5, or DOS XE? Or custom DOSes like SpartaDOS (their v4.41 rev2 manual only describes the boot sector data)? There's no way the DOS 2.0 format, which only supports up to 1023 sectors with 128 bytes each, would work properly for any of the larger media available.

 

Doing searches here, in Google, or elsewhere doesn't turn up much of anything. I don't know if I've been using the wrong search strings ("Atari DOS FS", "Atari DOS file system", "Atari FSM", etc.) or what... but nothing gives the actual details for how the data is stored on the disk.

 

Is there a list of the various FSes and how they are stored? If not a list, do people know what to search for or what resources are available to find out about them?

 

Thank you!

[dmsc]

Hi!

58 minutes ago, Zolaerla said:

As the subject says. I've been trying (and failing) to find detailed information on the actual file systems used by various DOSes on the Atari. I have only found full details for the old DOS 2.0 720 sector SD format. I already know FAT12/16 since I coded for MS-DOS back in the day, but that would have compatibility options with the Atari OS, at least for booting.

 

What about the other DOSes like DOS 3, DOS 2.5, or DOS XE? Or custom DOSes like SpartaDOS (their v4.41 rev2 manual only describes the boot sector data)? There's no way the DOS 2.0 format, which only supports up to 1023 sectors with 128 bytes each, would work properly for any of the larger media available.

 

Best resource, the Altirra Programmer's Reference Manual, download from: 

 

 

From page 100 the format of DOS 1, 2, 2.5, 3, MyDOS and SpartaDOS are described in full detail.

 

Have Fun!

 

[Zolaerla]

3 hours ago, dmsc said:

From page 100 the format of DOS 1, 2, 2.5, 3, MyDOS and SpartaDOS are described in full detail.

 

Have Fun!

 

 

Man, where has this guide been hiding while I've been learning to code on this system? I only found the Altirra hardware reference on my own, not this one. Thank you so much!