Terminators were/are used for the same thing they are always for,
impedance matching. This minimizes signal reflections and extraneous
noise. This is true with any transmission line. They aren't used for
drive select.

I have sitting here in front of me a Teac Model: FD-55GFV-17-U Floppy
Disk Drive. The terminator is a 16 pin DIP resistor pack. Right next
to it there jumper block with the labeled DS0, DS1, DS2, and DS3.
This translates as Drive Select 0, Drive Select 1, Drive Select 2,
and Drive Select 3. What these jumpers do is determine which drive
select line the FDD will respond to. If you connect this to a typical
Wintel box with a straight through cable (no twist) DS0 will
correspond to drive A: and DS1 will correspond to drive B:. (I think.
It's been a long time. :-))If any other position is used I would be
very suprised if a Wintel box could even find it much less boot from
it.

NOTE: The labels on these jumpers will vary with diffrent
manufactures.

SOMETHINGS TO TRY
=================
Take a diffrent drive that you know works and put in this system in
place of the malfunctioning one.

If it boots you know something is wrong with the drive.

If you have the same problem change the cable. Again use one you know
works. Just because it's new doesn't mean it's a good cable.

Make sure you are using a cable with a twist in it. The twist
switches the Drive Select lines around. If there is no twist and both
drives are set for the same ID it won't boot from them.

If you have to go looking for jumpers be aware that many newer drives
either don't have them where they can be changed or they will be
soldered in and risky to change without the right skills and
equipment. If I remember correctly, Drives intended for Wintel boxes
come jumpered to DS1.

On Wed, 9 Dec 1998 12:22:33 -0800, David Gillett wrote:

>  In the Olde Days, The floppy at the end of the ribbon cable
>required insertion of a "terminator" -- usually a SIP resistor pack
>-- and whether the drive would respond as "primary" (A:) or
>"secondary" (B:) depended on the presence or absence of this
>component.
On Wed, 9 Dec 1998 12:22:33 -0800, David Gillett wrote:

>  In the Olde Days, The floppy at the end of the ribbon cable
>required insertion of a "terminator" -- usually a SIP resistor pack
>-- and whether the drive would respond as "primary" (A:) or
>"secondary" (B:) depended on the presence or absence of this
>component.

--

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