drz@csri.toronto.edu (Jerry Zarycky) (12/20/88)
Help!
I'm trying to get a SCSI controller to work with my newly purchased SCSI drive.
Background:
I have an A2000 with 1 meg of memory and 1.2 ROMS.
I have purchased the 2090A controller card, and as instructed have removed the
autoboot EPROMS in order to make it work with the 2090A and 1.2.
To test out the system, I borrowed an old Rodime 10 Meg ST-506 drive from work
and formatted it with a boot (OFS) partition and a FFS partition.
It worked beautifully.
Now that my appetite was whetted, I purchased a MiniScribe 8051S SCSI drive
and tried to install it. I went through the Prep program and was pleased
to find that it was on the list of supported drives.
However, the Prep command says that the drive has 965 cylinders (and 4 heads)
while my documentation says it has 745 cylinders (and 4 heads).
Worse yet, my docs don't tell me how many blocks/track.
The upshot is that I can prep the SCSI drive, format a small OFS partition,
but trying to format the second FFS partition fails immediately after
it prints the first message (e.g.)
Formatting cylinder 31, 750 to go.
Help!
Can some kind soul tell me what is going on, or better yet, send me
a MountList with all the appropriate goodies in it, including
BlocksPerTrack?
I've just spent 6 straight hours working with on it a friend of mine who will
have the same setup (when we are done) and he is waiting anxiously as well.
Thanks for any and all replies.
Jerry Zarycky
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BITNET: drz@csri.utorontogrwalter@watcgl.waterloo.edu (Fred Walter) (12/20/88)
In article <8812200701.AA15577@ellesmere.csri.toronto.edu> drz@csri.toronto.edu (Jerry Zarycky) writes: >Help! >I'm trying to get a SCSI controller to work with my newly purchased SCSI drive. > >Background: > I have an A2000 with 1 meg of memory and 1.2 ROMS. >I have purchased the 2090A controller card, and as instructed have removed the >autoboot EPROMS in order to make it work with the 2090A and 1.2. >To test out the system, I borrowed an old Rodime 10 Meg ST-506 drive from work >and formatted it with a boot (OFS) partition and a FFS partition. >It worked beautifully. > >Now that my appetite was whetted, I purchased a MiniScribe 8051S SCSI drive >and tried to install it. I went through the Prep program and was pleased >to find that it was on the list of supported drives. >However, the Prep command says that the drive has 965 cylinders (and 4 heads) >while my documentation says it has 745 cylinders (and 4 heads). >Worse yet, my docs don't tell me how many blocks/track. I have the same setup (2000, 2090A, 1.2 roms, 8051S) and it works. With SCSI there is a logical mapping done and what you see at the connector at the back of the disk doesn't have to have anything to do with the actual physical drive geometry. Physically the drive has 745 cyl, 4 heads, 28 blk/cyl and internally it is RLL-encoded to get that capacity. However, one of the configurations (the one prep uses) is 965 cyl, 5 (not 4) heads and 17 blk/cyl. This is what I use. I get about 290K/sec reads (diskperfa, 32K buffer) with this. Another guy I know with the same hardware uses 1204 cyl, 4 heads and 17 blk/cyl and gets 340K/sec reads. As soon as I manage to get a-hold of docs describing how the logical blocks are laid out I'll figure out what layout is best for speed (for my drive at least). fred