Will The Grand Master Of Disk Controllers step foreward?

From: Don Maslin <donm_at_cts.com>
Date: Fri Apr 16 16:21:11 1999

On 16 Apr 1999, Eric Smith wrote:

> > 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.

Sorry Eric, but the spin motor is identical to the ones used in the
Shugart SA80n series - 120 VAC 60Hz 1.6 Amp. The rest of the power
requirements come in through a 6-pin connector, also identical to the
Shugart, so I would assume +5 VDC, -5 VDC (maybe), and 24 VDC. Probably
to the same pinout as the Shugart.
 
> You *might* be able to get a Q2040 to run at 5 Mbps, but I've never
> personally seen it done.

I have a hazy recollection of running one on a latter day HDC to view data
contents, but the details elude me now.
                                                 - don
 
Received on Fri Apr 16 1999 - 16:21:11 BST