Atari Disk format specs

[Tezz]

Hi all,

 

er.. I need a bit of a memory jog. I am about to image my Atari disks so I can back them up onto CD and also access them under emulation and of course post anything unique here on the forum.

 

I use the Catweasel controller on the Amiga but, it''s been a while since I used it and I've lost my multidisk.device listing

 

As I have just read up on the net, the 1050 drive could write the following:

 

1) Single-Sided, Single-Density, 90K which was 810 compatible

2) Single-Sided, Dual-Density, otherwise known as "Enhanced Density" because it is not true double-density

MFM 40 tracks x 26 sectors/track x 128 bytes/sector = 128K capacity

 

I need a little help with the nessasary fields on the Amigas DOS mount device can anyone tell me what is the correct BlockSize should I use? and how many BlocksPerTrack? Is a disk one surface when it's double density?

 

Here's the listing below........

 

/* multidisk file system entry

*

* This mounts a logical device on catweasel unit 0 for reading 180K Disks

*/



FileSystem = L:CrossDOSFileSystem

Device      = multidisk.device

Unit     = 0

Flags    = 24  /* makes an Atari 800 XL 180 Kbytes single-sided driver */

BlockSize = 512

Surfaces = 1

BlocksPerTrack = 9

Reserved = 1

Interleave  = 0

LowCyl      = 0

HighCyl     = 39

Buffers     = 5

BufMemType  = 1

StackSize   = 2048

Priority = 5

GlobVec     = -1

DosType = 0x4D534400

Activate = 1

As always, any help appreciated... Thanx Tezz

[miker]

hmmm... Shouldn't be: BlockSize = 256

 

The 512B sectors are available in "IBMSD" density in some modified disk drives...

 

But i may be wrong anyway...

[miker]

and... maybe BlockSPerTrack = 18

 

/who the heck disabled editing posts here, wrrrrrr!/

[voy]

Did you try to use 551conv program? Few years ago I was using this cool prog to read Atari disks directly from the Amiga 5.25" drive and it was working ... As I remember, I hooked up an original Amiga 3.5" drive to XF551's Shuggart connector... An Atari XL/XE with 3.5" disks - it was amazing!

 

I was suprised when I discovered that 551conv can read such prepared disks ...

 

Here is the link to 551conv:

 

http://www.aminet.net/~aminet/misc/emu/551conv.lha

 

and to its GUI:

 

http://www.aminet.net/~aminet/misc/emu/551convGUI.lha

 

Now I use PC-TASK 4.40 emulator with APE 1.17 and SIO2PC cable with CTS line active. This is the best solution for Amiga-Atari fan like me ...

[Tezz]

Thanks for that everyone, I will try to put the device driver together later this week.

 

voy Did you try to use 551conv program? Few years ago I was using this cool prog to read Atari disks directly from the Amiga 5.25" drive and it was working  ... As I remember, I hooked up an original Amiga 3.5" drive to XF551's Shuggart connector... An Atari XL/XE with 3.5" disks - it was amazing!

 

Yes, thanks voy. I have used 551 conv before and I have recently downloaded the latest from Aminet. My current Amiga set-up has a PC 5.25" drive connected to the Catweasel controller but, I do have an old Amiga 5.25" drive which I think is Amiga 500 only compatible. I guess failing setting up a new driver I could set-up my Amiga 500 and image the disks to an Amiga floppy and then copy the images to my Amiga tower for burning to CD/DVD.

 

Must archive these old 5.25" floppies !! I doubt that Verbatims lifetime guarranty will ensure that they will read for ever!!