15 Apr
1999
15 Apr
'99
10:35 p.m.
Specifically the WD-1000-5 disk controller. These are
the ones that
[...]
If you are intimately familiar with this legendary
interface, I would
like to hear from you. I need to figure out how to modify it for 8"
harddrives.
Regrettably I no longer have the manual or schematics for these, so a lot
of this is from memory.
The WD1000-5 was the WD1000 repackaged on an 8" * 5.75" board, to match the
form factor of 5.25" drives.
The original WD1000 and WD1001 had both 34 and 50 pin drive control
connectors. I'm guessing that the WD1000-5 left the 50 pin connector out.
However, you only need to scramble the pins appropriately, as the actual
signals are the same. All odd pins are ground on both connectors; the others
should map thusly:
34-pin 50-pin signal
2 2 *RWC reduced write current
4 4 *HS2 head select 2
6 40 *WG write gate
8 8 *SC seek complete
10 42 *TK0 track 0
12 44 *WF write fault
14 14 *HS0 head select 0
16 NC
18 18 *HS1 head select 1
20 20 *IDX index
22 22 *RDY ready
24 36 *STEP
26 26 *DS1 drive select 1
28 28 *DS2 drive select 2
30 30 *DS3 drive select 3
32 32 *DS4 drive select 4
34 34 *DIR step direction (in when asserted)
The radial data connectors are the same for both drive sizes.
The bigger problem is that 8-inch drives used a data rate of 4.34 Mbps rather
than 5 Mbps. I seem to recall that the WD1000 had a jumper setting for this.
If they removed the 50-pin drive control connector, they probably also removed
the jumper and supporting circuitry.
Also, does anyone have docs for the Quantum Q-2040
8"
Winchester? I dunno what kind of power to feed it (24v sounds correct,
but I seem to recall it used 110vac also!), and so on.
No data here, but almost certainly not 110 VAC. Probably 24V AC and 5V DC.
You *might* be able to get a Q2040 to run at 5 Mbps, but I've never
personally seen it done.