ESDI Disk for Sun

[kranenbu at HLERUL5I.BITNET]

> I would like to know if anyone has succeeded in hooking up the MiniScribe
> 9380E to Sun 3/60's SCSI port, and running, via the MD21 ESDI/SCSI
> controller/converter.

Yes, we have a 9380E as the second disk in a 3/160 with SCSI-board and
MD21 converter (running SunOS 3.5).

To get it working we had to configure the drive for SOFT-sectored
operation and sacrifice one sector on each track.  Our initial attempt to
format the drive in hard-sectored mode (1218 cyl, 2 spare, 15 head, 35
sec/track) ended with a "Mode Select" failure from the ESDI-controller.
According to the Emulex manual, this error message can have a variety of
causes, but my guess is that the controller did not accept the geometry
parameters passed to it by "diag".  Next we jumpered the drive for
soft-sectored operation resulting in success- fully completed format
operation, but a subsequent surface analysis showed quite a lot of bad
sectors most of which (but not ALL!) had sector number 35.  The first 20
or so could be re-mapped on spare sectors/cylinders, all the rest produced
re-mapping errors (no more spares available).  Being pragmatic, we dropped
sector 35, resulting in 2 additional bad sectors from the surface-analysis
test.  So the final disk geometry we settled for is: 1218 cyl, 2 spare, 15
head, 34 sectors/track. (capacity now: 310,5 MBytes).

I checked with the supplier, but they could not tell me how many sectors
are guaranteed to be usable in soft-sectored mode. Still, we are satisfied
since the price per MB nevertheless is very competitive.

P. Kranenburg
Dept. Comp. Sc.
University of Leiden, Netherlands
e-mail: kranenbu at hlerul5i.bitnet