Mark Willis wrote:
> Seriously, for once, here;  I'm looking at making a cable tester, for
> the all-too-frequent task coming up of figuring out which wire to solder
> to where on some cable assemblies I'm manufacturing.

snip---

> General idea - pick up a palmtop or desktop, use it as a tracing tool -
> probe with that serial port's RD line through all the wires in there,
> common the Shield wire on both ends.  Then if I have a 25-pin cable with
> pins 2 and 3 crossed on the other end, I'll get "Pin  2 Pin  3 Pin  2
> Pin  3 "  etc. output again and again;  Exactly what I want to know,
> really!
> Comments?

Trade the palmtop in for a battery, pic, and LCD.
Set all lines low, send your code out on a single wire at a time, and
step them through.
Use any line as your ground reference.
Any other line will show up in turn with its signature, even the shield.

Merry Chrismas...

Don McKenzie    mailto:don@dontronics.com      http://www.dontronics.com

World's Largest Range of Atmel/AVR and  PICmicro Hardware and  Software.
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