DB9 male to 3.5mm stereo RS232 adapter cable

starfire151 · Joined: 01 Apr 2007 Posts: 195

My apologies if this is not the correct location to ask this question but I've tried the CCS home page and can't seem to get an answer...

Does the cable listed as "Serial PC to Prototype Board Cable" have the following pinout?

tip of 3.5mm connector goes to pin 3 of the DB9 connector
ring of the 3.5mm connector goes to pin 2 of the DB9 connector
ground of the 3.5mm connector goes to pin 5 of the DB9 connector

I checked with Amazon but the cable adapters they list have the tip and ring pins reversed.

Thanks for any information.

starfire151 · Joined: 01 Apr 2007 Posts: 195

That should be DB9 FEMALE, not DB9 male... Sorry...

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

I looked at it and you're right, it appears that the CCS cable is wired
the opposite of every commercially available cable that's out there.
You could email CCS support and ask them about this.

starfire151 · Joined: 01 Apr 2007 Posts: 195

Yeah. This seems a little lame...

I looked at ordering the cables from CCS. They want $8 each plus $5 each for shipping! Amazon wants $7 each with free shipping but pins 2 and 3 are reversed.

It looks like I'll just build my own...

Thanks for checking on this, though.

newguy · Joined: 24 Jun 2004 Posts: 1911

Forcing the use of a custom cable is smart from a cash flow/sales perspective. Forcing the use of a custom cable on a bunch of people who have technical backgrounds just alienates said people.

Ttelmah · Joined: 11 Mar 2010 Posts: 19553

You;ll find the male cables are done the opposite way round. I doubt if it was deliberate, probably they original prototype was built with a female connector, not a male one, so the two pins ended up reversed...
You can use an 'off the shelf' male cable and a pin to pin female to female adapter.

temtronic · Posted: Tue Feb 28, 2017 1:26 pm

I'm more upset that 'they' (the computer World) swapped 2 and 3 (rxd and txd) when the PC World went from DB-25 connectors to DE-9 connectors.
So much for 'standards'.....

Jay

Ttelmah · Joined: 11 Mar 2010 Posts: 19553

I remember being told by a guy at IBM, this was because they wanted to switch the PC from being a DTE device to a DSE device, but had already used the DE9 female connection for the video.
Stupid, but 'sort of makes half sense'....