Newbie RS-232 question

Nov 25, 2006 2 Replies

I've got a couple of female-female RS-232 cables.



I initially thought they were null-modem cables, but when I checked the pin connection, this is what I found:



1 -> 7,8
2 -> 3
3 -> 2
4 -> 6
5 -> 5
6 -> 4
7 -> 1
8 -> 1
9 -> not connected

As I understand it, a null modem should be like this:



1 -> 4
2 -> 3
3 -> 2
4 -> 1,6
5 -> 5
6 -> 4
7 -> 8
8 -> 7
9 -> not connected

There's no sign of a part number on either cable.



Any ideas of what I have?



Bob Pownall


See

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Thanks! Looks like they _were_ null modem cables, just not the type I was familiar with. Specifically, they're null modem cables with partial handshaking, and I was only familiar with null modem cables with loop-back handshaking.

I'll have to bookmark that site - looks useful.

Bob Pownall

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