Mark Willis wrote:
>
> On these cables, most always several wires are already, or if not WILL
> be, cross-connected at the connector end (for example, Interlink cables,
> Null Modem cables, etc.)  Said "pins 2 and 3 crossed" in my post,
> perhaps "cross-connected" would be a better term, and should have said
> pins 1 & 6 (for example, an Interlink 9-pin cable has these connections,
> as we all know;
>
> Left side DE-09F           Right side DE-09F
>  RxD          2      3      TxD
>  TxD          3      2      RxD
>  DTR          4      6+1    DSR + DCD
>  Ground       5      5      Ground
>  DSR + DCD    6+1    4      DTR
>  RTS          7      8      CTS
>  CTS          8      7      RTS
>
> I'm cutting a "regular" Interlink / modem / whatever cable in half, the
> "existing" end may be already cross-connected or may not, and I need to
> end up with the cross-connected wires all set inside there by the time
> I'm done.  If I set all lines low, "it won't be pretty", so to speak,
> two outputs pulling things in different directions, hard on the PIC <G>

So you've cut the cable and there is a plug on one end only,
the way I would do it is use a signal generator and a signal tracer.

The connector end would plug in to the signal generator
which could be your laptop or just a PIC, trace the wire and solder it
to the appropriate pin on the new connector, press a key to switch
to the next line.

Use 1KHz as a starting frequency, higher might sound better but will
couple
to the other wires.

I have in my phone tool kit a PIC signal generator for tracing phone
lines,
I use a LM386 with a fet on the input to trace the signal (non contact).
The live wire detectors are also good, though contact type tracer would
be
better for your application.
--
Peter Cousens
email: p.cousens@cwcom.net  or  p.cousens@virgin.net
smail: 48, Yarmouth Cresent, London, N179PQ, England.