PC formatted 5.25 disk drive mountlist - help, please

[pyrre]

Anyone have something like this?
Or should the standard PC1 mount list work for 5.25 disk drives as well?

And

have anyone tested this mount list for C64 formatted disks if it works?

BTW my disk drive has a switch to select 40 or 80 tracks. How does that influence disks having 48 tracks? Would selecting 80 tracks on the disk drive let the mount list limit to only 48 TPI?

[robo-ant]

Anyone have something like this?
Or should the standard PC1 mount list work for 5.25 disk drives as well?

This is the mountlist that I used:

/* CrossDOS file system entry for 5.25" drive.
 */

FileSystem     = L:CrossDOSFileSystem
Device         = mfm.device
Unit           = 2
Flags          = 1
Surfaces       = 2
BlocksPerTrack = 9
Reserved       = 1
Interleave     = 0
LowCyl         = 0
HighCyl        = 39
Buffers        = 5
BufMemType     = 0
StackSize      = 600
Priority       = 5
GlobVec        = -1
DosType        = 0x4D534400


I had only a double-density 5.25" drive (Amiga A1020).

Be aware that this drive does not detect disk changes, so you have to issue 'diskchange' commands yourself!

have anyone tested this mount list for C64 formatted disks if it works?

That's software for reading 1541 disks and making disk images.  It is not a mountlist.

Yes, it does work, but you have to change the rotation speed of the disk drive for it to work reliably.  IIRC, the instructions for doing that are included in the archive.  The software works well for reading 1541 disks after that (and CBM 2040 disks, too!) but MS-DOS disks are problematic then.

You cannot write to 1541 disks with this software.  1541 disks are tricky because the data rate is different on different tracks.

I experimented a bit with the rotation speed, and IIRC, the sweet spot for me was 283 rpm.  That allowed me to read Apple ][, C=1541, and Atari (forgot the drive model) disks into images well, and still be able to read MS-DOS disks.  Writing to MS-DOS disks at that speed often corrupted them.

[pyrre]

I had only a double-density 5.25" drive (Amiga A1020).

I have this 5.25 disk drive. And i have no clue to what it can/cannot do...

Be aware that this drive does not detect disk changes, so you have to issue 'diskchange' commands yourself!

What is that command?
When i insert a disk and close the lever the disk shows up on the desktop immediately. And when opening it the disk disappears from the desktop immediately... Is that disk change?

[robo-ant]

I have this 5.25 disk drive. And i have no clue to what it can/cannot do...

Cool!  It's a lot smaller than the Commodore 5.25" drive.

When i insert a disk and close the lever the disk shows up on the desktop immediately. And when opening it the disk disappears from the desktop immediately... Is that disk change?

Yup.  My experience with 5.25" drives on Amiga is limited to the A1020, which didn't have this feature.  It looks like your drive is more Amiga-compatible than Commodore's own.

[pyrre]

@robo-ant
It still reports error.
read/write error on block XXX
error = 23
Block not found

What could that be?

(reading pc disks)

[rkauer]

 A bad disk. :roll:

[pyrre]

A bad disk.  

It gives the same response to ALL the disks....
All of the 10 disks cannot be bad.... :-?

[mark_k]

Don't worry, the disks are probably fine! Here's some info on how to get your drive working with them.

Commodore's original A1020 5.25" drive has 40 tracks and cannot detect disk changes (with that drive, you need to issue a "DiskChange DF2:" etc. command in a CLI whenever you change disks).

Your drive is different. In 80-track mode, it acts just like a normal Amiga external drive. You could put in a blank 5.25" disk, format it to 880KB and use the disks just like normal Amiga OFS/FFS floppies. It detects disk changes, so you don't need to worry about that.

PC floppies have 40 tracks. Therefore when your drive is in 80-track mode, you need to tell CrossDOS to double-step the heads. You do that by using a different DosType line in your mount file. With a 40-track drive, you would have "DosType = 0x4D534400". For your 80-track drive you need to change that to "DosType = 0x4D444400". (In ASCII those DosTypes correspond to MSD\0 and MDD\0.)

With that change you should be able to read your PC disks correctly. So for general use (Amiga and PC disks), leave your drive in 80-track mode.

For certain other uses (e.g. if you try reading C64, Atari or Apple II disks using software on Aminet), you might need to set the drive to 40-track mode if the software doesn't have an option to double-step the heads.

When your drive is in 40-track mode, it double-steps by itself. You should change the trackdisk step delay when using the drive in 40-track mode. You could change it to 6000 microseconds. I think there's a program called SetTDDelay on Aminet which you can use.

Also, in 40-track mode don't try using Amiga floppy disks! Trackdisk.device will think the drive has 80 tracks so that won't work properly.


-- M