OSI-MF I looked up the specs, and the ACIA was clocked at 125Khz, in a divide by
1 configuration. 8E1

OSI-DF The 8" disk systems stored ~250K worth of data, and wrote at 250Khz. I
think it had 77 tracks, 12 sectors (not sure). 


FWIW, Some notes I found had the following:
'C','W',track#, char?, $76, sector#,#pages,data,$47,$53
| **** index 5 bytes *****|

Some photocopied OS65D pages had the following

Track 0 format is as you stated. 
- 10ms delay, 
- load address hi,lo 
- page count, 
- data

All the other tracks are formatted:
- 10ms delay, 
- 2 byte track start code $43, $57 
- BCD track # 
- Track type code (always $58) 
- [Any mixture of various length sectors. Total page count can not exceed
8 pages if more than one sector is on any given track.]

Each sector is written in the following format:
- previous sector length(4 if none before) times 800 microseconds of delay
- sector start code $76
- sector number in binary
- sector length in binary
- sector data

Directory format:
Two sectors (1 & 2) on track 12 hold the directory information.
Each entry requires 8 bytes, Thus there are a total of 64 entries between
the two sectors. The entries are formatted as follows:
0-5 ASCII character name of file
6   BCD first track of file
7   BCD last track of file (included in file).


There is a copier utility on track 1 sector 2, it should be loaded at
$0200 with "CA 0200=13,1  To start it type "GO 0200"

5 1/4 Mini-Floppy Disk layout OSDV3.1

Program          Track, sector,  start,  #pages, go addr, comment
OS65D V3.0 pt1    0       1       2200     8               1st pg overlaid
OS65D pt2         1       1       2A00     8               by Trk6 &11
BASIC pt1         2       1       0200     8
BASIC pt2         3       1       0A00     8
BASIC pt3         4       1       1200     8
      pt4         5       1       1A00     8    20c4-21c3 overlaid by T12,3
      pt5         6       1       2200     1
ASSEM pt1         7       1       0200     8
ASSEM pt2         8       1       0A00     8
ASSEM pt3         9       1       1200     5
EM    pt1        10       1       1700     8
EM    pt2        11       1       1F00     4
Dir Pg 1         12       1       2E79     1           overlaid by T12,4
Dir pg 2         12       2       2E79     1           overlaid by T12,4
Basic overlays   12       3       20c4     1
put/get overlay  12       4       2e79     1
copier/trk0 Util 13       1       0200     5
BEXEC*           14       1       327F     8
COMPAR           39       1       0200     5   0200   Not present on all
                          2       2000     2

