RS-232 (was Re: IBM 3101 Dip Switches Configuration)

From: Ethan Dicks <>
Date: Sat Jan 26 19:08:55 2002

--- Tony Duell <> wrote:
> > > My standard rule for dealing with an RS232 in-yer-face is to plug
> > > it in without a null modem and see if it works...if it doesn't,
> > > then plug in a null modem.
> >
> > I either use a traffic light or my magic cable. I built it when I was
> > 16.
> ^^^^^^^^^^^^^
> If that's what I think it is (an in-line adapter with LEDs monitoring the

> most important signals), then I call it a Xmas Tree

Yes. Same thing, different name.

> Certainly something _everyone_ who works with serial comms should get.
> They're not expensive (about $10 to $20, I guess).

Rat Shack has one for around $14, with 7 bicolor LEDs. The nice ones
have one red and one green LED for each signal (23 or 24) and can
be used to divine strange devices and jumper up a fix.
> > has the property of magically unhosing serial connections
> If it manages to 'unhose' the hardware handshakes on an HP82164
> HPIL-RS232 interface I'll be seriously impressed!...
> A cable to link 2 82164s has to sawp RTS with DSR and DTR with CTS.

Wahoo! That _is_ odd.


Do You Yahoo!?
Great stuff seeking new owners in Yahoo! Auctions!
Received on Sat Jan 26 2002 - 19:08:55 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:34:58 BST