25 Feb
1998
25 Feb
'98
12:30 a.m.
You know, I have a WD-1000-XX controller that supposedly can talk to
these drives. It also can talk to 5.25" drives.
These controllers are SASI on the 'other' end (I think).
Hmmm. I don't see many SA-1000's being offered for sale . ..
Jeff
Those are
8.4MB drives. Not SCSI, not even ST-506. Those are 8"
Shugart mechanisms in there, 4 heads by 256 cylinders. I forget
how termination worked in those units (haven't seen one in action
in at least 12 years). And yes, the write protect switch and the
Probably an SA1000 type interface. It's similar-ish to an ST506 interface
in that there's a control cable that goes to all the drives and a
separate data cable from each drive to the controller.
The control cable has 50 wires, and is sort-of 8" floppy drive like. In
fact you can have a mixture of 8" SA800 floppy drives and SA1000
winchesters on the same control cable (up to 4 drives total). The data
cables were only used on the hard drives, of course.
You terminate the control cable at the last drive (furthest from the
controller). The data rate is 4.34Mbps.
Here's a pinout od the control cable. All odd numbers are ground...
2 Reduce Write Current*
4 Head Sel 2*
8 Seek Complete*
14 Head Sel 0*
16 Sector Pulse*
18 Head Sel 1*
20 Index Pulse*
22 Ready*
26 DS1*
28 DS2*
30 DS3*
32 DS4*
34 Step direction (low = in)
36 Step Pulse*
40 Write Gate*
42 Track 00*
44 Write Fault
Rest not used.
The data cable has the same pinout as an ST506 data cable, apart from an
extra clock from the controller to the drive on pins 9 (+ve) and 10
(-ve).
Ward Griffiths
-tony