2.5 KiB
Disk: Victor 9000
The Victor 9000 / Sirius One was a rather strange old 8086-based machine which used a disk format very reminiscent of the Commodore format; not a coincidence, as Chuck Peddle designed them both. They're 80-track, 512-byte sector GCR disks, with a variable-speed drive and a varying number of sectors per track --- from 19 to 12. Disks can be double-sided, meaning that they can store 1224kB per disk, which was almost unheard of back then. Because the way that the tracks on head 1 are offset from head 0 (this happens with all disks), the speed zone allocation on head 1 differ from head 0...
| Zone | Head 0 tracks | Head 1 tracks | Sectors | Original period (ms) |
|---|---|---|---|---|
| 0 | 0-3 | 19 | 237.9 | |
| 1 | 4-15 | 0-7 | 18 | 224.5 |
| 2 | 16-26 | 8-18 | 17 | 212.2 |
| 3 | 27-37 | 19-29 | 16 | 199.9 |
| 4 | 38-48 | 30-40 | 15 | 187.6 |
| 5 | 49-59 | 41-51 | 14 | 175.3 |
| 6 | 60-70 | 52-62 | 13 | 163.0 |
| 7 | 71-79 | 63-74 | 12 | 149.6 |
| 8 | 75-79 | 11 | 144.0 |
(The Original Period column is the original rotation rate. When used in FluxEngine, the disk always spins at 360 rpm, which corresponds to a rotational period of 166 ms.)
FluxEngine can read and write the single-sided variant of these. (Double-sided will be trivial to do, it's just not done yet.)
Reading discs
Just do:
fluxengine read victor9k-ss
You should end up with an victor9k.img which is 627200 bytes long.
Big warning! The image is triangular, where each track occupies a different amount of space. Victor disk images are complicated due to the way the tracks are different sizes and the odd sector size.
Writing discs
Just do:
fluxengine read victor9k-ss -i victor9k.img
Big warning! This uses the same triangular disk image that reading uses.