Configurable D-sub Adapter


Thread Starter


We have several devices that use DB-9 connectors for serial or other communication, and inevitably I end up coming across a new or legacy device that I don't have the correct cable for. So every time this happens, I have to either A) Chop and splice a cable or two, or B) Order one and wait a few days. Neither situation is ideal, and I do like to have a tool like this in my bag of tricks.

Does anyone have something you like to use for a reconfigurable 9-pin adapter?
This is the one I like for that situation:

A mini breakout board, about 1.5" square, plenty small enough and light enough to plug right into the DB9. Comes in both male and female, two screw types, and they have similar products for a lot of other connectors, including modular jacks.
B&B Electronics sells a RS-232 breakout box that might be useful as a configurable crossover between two cables. It's fitted with large DB25 connectors, but you should be able to use it with standard 25-pin to 9-pin adapter plugs or adapter cables as needed.

Does anyone besides me care that references to data cable connectors should correctly indicate the shell size? (e.g. B = approx. 2" wide as used on old style DB25 25-pin serial connectors, E = approx. 1" wide as used on less old DE9 9-pin serial connectors and DE15 15-pin VGA connectors).

Curt Wuollet

First you get a soldering iron and a bunch of DB-9s, then you get a spool of high quality cable. Some hoods and you're ready to go.

Infinitely reconfigurable, repairable and much higher quality. Back when serial was king, there was no way you could find all the wacky combinations that some terminals and printers used, but you could make any of them. Great for ad hoc cables. As far as I'd go with the kludges are the connectors that use silver satin and let you poke the pins in the holes as you please. The only problem is when you need to jumper two or more pins.

If you're going to keep needing the cable, try making a double-ended DE9 adapter.

We have a number of weird things still running in our plant (some are new, actually...) and rather than make a cable for each one, I make a male-female DE9 adapter with the connections inside configured for whatever it is. I have one straight through serial cable with miniature gender changers, a miniature null modem adapter, and several of these double-ended DE9 connectors. That gets me online with almost everything that doesn't require a cable that has electronics in it.

For quick tests, I also use these sometimes: