S-100 bus termination

From: dave dameron <ddameron_at_earthlink.net>
Date: Sat Jul 25 15:45:14 1998

At 07:26 PM 7/24/98 -0500, you wrote:
>I was digging through some S-100 cards and came upon a Godbout active
>terminator. Do all S-100 buses require external termination, or did more
>have it built into the mobo? Specifically, do I need to stick this card
>into my IMSAI?
>
I don't remember many ads besides Godbout about active terminators. What
seemed more important was shielding - running ground traces between the
signal lines, at least for all the ads for "shielded" motherboards.
Maybe a few of the lines would be helped by terminations. It was these where
1k pullup resistors wouls be put on cards. 8 cards with 1k resistors would
be 125 Ohms, distributed.

Terminations of longer ribbon cables seemed more important. I remember early
floppy drives with a dip resistor pack (220/330 Ohms?) that you put on the
last or only drive. Whatever happened to this? A few years ago I bought a
1.44 floppy drive and asked about terminations (Did it require or have them?
Controlled by a jumper?) The tech support people looked at me like I was
from Mars. Doesn't scsi use terminators?

Try your S-100 both ways, and see if it helps or hurts.
-Dave
Received on Sat Jul 25 1998 - 15:45:14 BST