[comp.sys.amiga.tech] Floppy drive cable for AT bridgeboard?

brett@smosjc.UUCP (Brett Coon) (07/10/90)

I tried setting up my A2286 AT Bridgeboard last night, and realized that I
somehow managed to lose the cable that connects the Bridgeboard with the 5.25"
disk drive.  I managed to find a cable and the appropriate connectors, but
when I connected it together, the Bridgeboard wouldn't boot.  According to 
the manual, the AT cable is supposed to have a few of the wires twisted, which
(hopefully) explains the problem.  Could someone please tell me which wires
get twisted so I can fix my cable?

Thanks,
-brett

-- 
|Brett Coon           |  uunet!smosjc!brett         |
|S-MOS Systems, Inc.  |  "You like 'em, anchovies?" |
|San Jose, CA         |            -Runaway Train   |

djh@metaphor.metaphor.com (Dallas Hodgson) (07/14/90)

In article <294@smosjc.UUCP> brett@smosjc.UUCP (Brett Coon) writes:
>I tried setting up my A2286 AT Bridgeboard last night, and realized that I
>somehow managed to lose the cable that connects the Bridgeboard with the 5.25"
>disk drive.  I managed to find a cable and the appropriate connectors, but
>when I connected it together, the Bridgeboard wouldn't boot.  According to 
>the manual, the AT cable is supposed to have a few of the wires twisted, which
>(hopefully) explains the problem.  Could someone please tell me which wires
>get twisted so I can fix my cable?

The twist on the cable is a convenience to allow both drive A: and B: to
be drive-select dumpered identically. If you use a flat cable, you can
move one of the drive select jumpers to get the desired effect.

This goes all the way back to TRS-80 days when the long 4-drive floppy cable
connecting the Expansion Interface to the drives had the select pinouts
modified at each connector. If the jumpers aren't right, nothing bad will
happen - either the drive won't select, or it will select simultaneously with
a different drive.