Re: SCSI HD connection questions, from a Complete Idiot[tm]

[JB3819@JB3819.SBC.COM]

In article <3e1h8l$fbc@netaxs.com>, <vsp@unix3.netaxs.com> writes:
> 
> It's an Apple SCSI card, dated 1990.  (Not sure on the revision, but the
> label on one of the chips says "341-0803 @1990 Apple" on it.)

Well... since it is the original Apple II SCSI card, I have some experience 
with it, but it has been awhile and the card is not at-hand.  When I get home 
this evening, I'll see if I can locate it to identify which rev you have.  I 
remember having a hell of a time getting a Rev.C version of the card when I 
bought the mine 5-ish years ago.  Ended up with a previous rev and got it 
upgraded (free).

>  The card is
> currently in slot one, not being used; when I put it in slot 7 and tried to
> boot a ProDOS utility, the boot sequence stopped dead until I put the card
> back in slot one.  (Could be a bad card; I'll be testing this over the
> weekend.)  All dipswitches are in the "down" position, if that rings
> any bells.

I'm not sure if the Apple SCSI card what the timeout is when the card goes 
looking for devices on the SCSI bus.  Sounds like that.  Also, if the card and 
the drive are strapped to the same address (not likely), a similar kind of 
thing can happen.

Try putting the card in slot 7 and not hooking it to the drive.  Don't know for 
sure what to expect, but the computer should give up on getting a response from 
that port and boot from floppy (I think).

> It was in a Mac, taken out, given an external case and presented to moi
> some time later.  Size and original manufacturer unknown.  It has two 50-pin
> ports that my SCSI terminator and cable plugged into nicely, as well as a
> SCSI ID counter; 

If it was in a MAC, it is almost certainly a SCSI drive.  I'm fairly sure the 
power requirments for such things are pretty standard, as are how they hook 
into external cases.

> As for the terminator, it's plugged directly into the other port; I'm not
> sure why I'd need another cable, as this is my only SCSI device.  Whether
> it provides power to it or not, I'm not sure, and less sure how to test this.

My disk drive had 25-pin cables in and out and I had a 50 pin terminator.  So I 
had to use a 25 to 25 cable from IIgs to disk and a 25 to 50 cable from disk to 
terminator.  If you've got the room to do it, plugging the terminator into the 
second connector on the drive should be fine.

As for termination power, I'm at a loss to know how to test whether or not the 
drive supplies it or not.  I don't think the A2 SCSI card did.  I know the A2 
HS SCSI card doesn't and the RamFast can (depending on strapping).  Which 
reminds me... I THINK the only thing you strap on the A2 SCSI card is the SCSI 
ID.  I'll see if I can find my old card / manual tonight sometime.

JAB ->-------