8" drive on a pc controller

From: Dwight Elvey <elvey_at_hal.com>
Date: Wed Apr 14 18:37:42 1999

Lawrence LeMay <lemay_at_cs.umn.edu> wrote:
> The explanation is that some signals are open
> collector driven, and thus you need 2200 Ohm pull up resistors.
> Does anyone know what the deal is, and is this really necessary, or
> just a nice idea that you can usually ignore...

Hi Lawrence
 First the bad news: Yes you must have pull-up resistors.
 Next the good news: Most drives have a socket that will
       either take a resistor network or jumpers to resistors.

 The idea here is the device at the end of the daisy chain
would be the only one with the pull-up resistors. This doesn't
effect the cables, only how you set up the optional parts
of the drives.
Dwight
Received on Wed Apr 14 1999 - 18:37:42 BST