Function Code 8 — Return Current Drive Parameters - Zenith Z-100 Reference Manual

Function Code 8 — Return Current Drive Parameters
When
completed, DL contains the number of active Winchester drives, DH contains
a number representing maximum usable heads, CH contains a number represent-
ing maximum usable cylinders, and CL contains a number representing
usable sectors with the two MSBs representing the two MSBs of the
usable cylinder number.
Function Code 9 — Initialize Drive Type Characteristics
Interrupt vector 41H should point to the new drive type parameter table, organized
as four sets (for the four possible drive types) of information. This is formatted
as follows:
Number of Tracks — Word
Number of Heads — Byte
Start Cylinder for current reduced write — Word
Start Cylinder for write precompensation — Word
Maximum number of bits to correct on data errors — Byte
Controller option byte:
Bit 7 — Disable retries
Bit 6 — Disable Error Correction Code (ECC)
Bit 0 to 2 — Step rate:
000 — 3 m per step
100 — 200 p.sec per step
101 — approximately 60 I Lsec per step
110 — 3 m per step
111 — 3 msec per step
Time-out value for read/write — Byte
Time-out for format — Byte
Time-out for disk diagnostics — Byte
Reserved — 4 Bytes
page 9.11
Disk Drives
maximum
maximum