At 06:59 PM 4/29/00 -0700, Shawn T. Rutledge wrote:
>On Sat, Apr 29, 2000 at 08:31:18PM -0500, Nate Bargmann wrote:
>> I agree it's bad, but I wonder how many would lug a UPS to the Field
>> Day site? Improved filesystems will help in this regard. Unfortunately,
>> just because one is using a laptop doesn't mean a power failure won't
>> occur. For example, I need to use a port replicator on this Thinkpad
>> 760ED in order to use an external keyboard. To power the laptop off of
>> AC, the unit has to be fed through the replicator and if that power
>> is lost, the laptop dies as the battery won't take over. So, it's
>> still a problem.
>
>Bummer. Shortsighted design on IBM's part.
Actually, if the 760ED is like most other IBM Thinkpads -- and the
documentation I've read implies that it is -- you do not need to
use a port replicator to use an external keyboard. Thinkpads tend
to have a single PS/2 connector onto which they multiplex mouse and
keyboard signals with shared clocking and other strangeness. What
you need is a keyboard/mouse connector cable (IBM Part 54G0441),
which is a y-cable with male PS/2 connector that attaches to your
760 and two female PS/2 connectors that accept an external keyboard
and mouse. If you want to see how all of this hooks up, surf over to
<http://www.pc.ibm.com/us/support/thinkpad/uguide/760x/mmxmst24.html#HDREXTKBD>.
And this being a ham list, you'll want to make the cable yourself. :)
The details to do that can be found under "ps2 keyboard Y adapter
for Thinkpads" at <http://csgrad.cs.vt.edu/~tjohnson/pinouts/#console>.
Enjoy!
...b, who knows way more than he wants to about Thinkpads and external PS/2
