[comp.sys.amiga] ST157 Hard Drive & Cable

kent@swrinde.nde.swri.edu (Kent D. Polk) (01/12/90)

Thanks to those who responded to my request for cabling & drive info
to hook up a ST157 SCSI to my 2090a controller.

First of all, it appears I was supposed to get a 2090A controller
manual with my 2500 - nope, I didn't lose it and nope, i'm not a
hardware pirate. :^) (Maybe I am since got the drive for free)

Anyway, pin one on the disk controller is towards the bottom of the
card. That's what I needed. I really do work with this kind of
stuff, but couldn't find any markings on the board to indicate which
was pin 1 and SCSI is new to me - didn't want to just go plugging
stuff in to see what would happen. Maybe I'm just going blind in my
old age.

Thanks again,
Kent Polk

kent@swrinde.nde.swri.edu (Kent D. Polk) (01/12/90)

In article <24859@swrinde.nde.swri.edu> kent@swrinde.nde.swri.edu (Kent D. Polk) writes:
>
>Anyway, pin one on the disk controller is towards the bottom of the
>card. That's what I needed. I really do work with this kind of
>stuff, but couldn't find any markings on the board to indicate which
>was pin 1 and SCSI is new to me - didn't want to just go plugging
>stuff in to see what would happen. Maybe I'm just going blind in my
>old age.
^^^ That's me.

I also should have mentioned that I got lots of info about things to
look for in aligning cables. Yes, I know all of those tricks, but
thanks anyway. For the benefit of those who don't have a 2090A, I want
to repeat that there are absolutely NO markings on the connector on the
board. The connector is completely symmetric. Yes, the cable is marked
with pin 1 & pin 1 on the drive is marked. Some mentioned about pin 1
on the cable - well it's a multicolored cable, so that goes out the
door, but that wasn't really a problem.

Actually, there was one clue that someone pointed out: all the pins on
one side of the connector are grounded. I saw this also, but
unfortunately, the connector housing on the drive covered up the solder
joints, so I would have had to disassemble the drive to find which side
was grounded there also and really didn't want to do that.

I don't know if I just didn't receive a 2090a manual or if it is not
included with the 2500. All of the software info & a bit of the
hardware info is in the little 2500 addendum manual, so maybe they
figured the 2090a manual was not needed. If this is the case, maybe
the location of pin 1 on the connector might ought to be included in
the monthly newsgroup posting (and in the manual).

Thanks again for your responses, The ST157N is a pretty nice drive -
not too fast though (28ms seek). I didn't try to boot off of it, but
would be concerned about the lengthy startup time being a problem.
My Rodime is already loading software several seconds before the
ST157 has finished.

Also, - Question: Is it possible with the 2090A to not have a boot
partition with a SCSI drive? I tried various strategies, but when I
went to format, format often just exited - as if it was finished - no
error or anything. 

Thanks,
Kent Polk