Formatted Capacity 250K 500K 1.2 MB
# of Heads (Sides) 1 2 2
# of Cyls (Tracks) 77 77 77
# of Sectors/Track 26 26 8
Total # of Sectors 2002 4004 1232
# of Bytes/Sector 128 128 1024
# of Bytes/Cluster 512 512 1024
# Sectors/Cluster 4 4 1
Total # of Clusters 497 997 1227
# Reserved Sectors 1 4 1
# of Hidden Sectors 3 0 0
# Sectors/FAT 6 6 2
# of FAT Copies 2 2 2
# Root Dir Entries 68 68 192
Media Descriptor FE FD FE
Recorded Density Single Single Double
MS-DOS Version Began 1.00 2.00 2.00
Change-Line Support NO NO NO
So it's important what kind of drive you have. Is it single or double sided and is it single or double density?
You should also be aware that even if these formats are some kind of standard, you can't read them with MSDOS as the sectors size is either 128 or 1024 byte where DOS only works with 512 byte!
So even if the above formats exist in theory they are not compatible with MSDOS. I think 8inch drives have never been in common use with MSDOS!
I guess it would be much easier to upload a sample of the raw files (you already dumped) to some web space and provide a link here for further examination...
Here's a Box link to my streams:
I'd really appreciate any assistance anybody can offer. My technical tools aren't my sharpest implements.
You can use the following parameters to decode the disk or use as a guide format:
-v360 -z3 -i4
dtc -m1 -f< stream filename or pattern> -i -f<image filename> v360 -z3 -i4 -l8
-l8 at the end will restrict the information on the console to format check only.
I guess it's a copy from a 5,25inch 1,2MB floppy...
Disk 8 is very weird with FM parts on it. Will look at it tomorrow.
No idea if this is just copy-protection, or a legit format from some unknown 8'' dos...
I've attached the decoded image, but it does not seem to contain anything useful, maybe some database?
Just a hunch, but... each record is 128 bytes, 0x40 means valid, 0x60 deleted, then the record number/offset etc. record itself is gibberish, maybe byte order is scrambled or has some simple encryption.