Third Party 4D35 Disks (I'm being bit)

[Dave Olson]

In <1991Jun6.221905.3291 at nntp-server.caltech.edu> woolstar at nntp-server.caltech.edu (John D. Woolverton) writes:


|     I had a nice, quiet, third party hitachi 3 1/2 drive in
| my temporary 4d25, and when they upgraded to the 4d35, it
| stopped working.  I am discussing it with my supplier, but I
| am curious what great design changes they made that broke a
| very common disk drive (used in our sparcs too).
|     Someone mentioned that the SCSI controllers changed from
| SCSI1 to SCSI2.  Isn't it backwards compatible.  Will other
| SCSI devices suddenly break?

The only real difference in the SCSI chips between the 25 and the
35 is that we are using a plcc version of the chip at 20 Mhz,
rather than a DIP at 10 Mhz.  This means that some of the internal
cycle times are shorter for the microcode, but that seems unlikely
to be your problem.

The 35 has a scsi driver much closer to irix 4.0 than that in 
irix 3.3.  All of the drives we have tested (including some
hitachi 3.5" drives) seem to work just fine.  What kinds of
problems are you seeing, and at what point (prom, kernel, both)?
--

	Dave Olson

Life would be so much easier if we could just look at the source code.