If you try to send an RS232 signal but your pinout is wrong, will anything be damaged? I don't think so. I say this because the difference between the cables used to transfer programming into a the old Pronto remotes and URC remotes that used mini plugs is the connection of Tx and Rx. With those remotes, if you use the wrong cable, you get an error message but nothing is damaged.

See [Link: bb-elec.com]

Basic RS232 uses, on the computer end, pin 3 to send, pin 2 to receive, and pin 5 for ground. (The modem end reverses the function of pins 2 and 3, so you instantly cannot say there's ONE definition for each pin.)

When you use a mini plug, you have three connections. The only connection that's more or less guaranteed is the sleeve being ground... because it almost always is on any mini plug. The only question is whether Tx is tip and Rx is sleeve, or Rx is tip and Tx is sleeve. And my experience programming remotes is that nothing gets hurt if you hook it up backwards.

So wire up a connector and try it out. If it doesn't work, reverse pins 2 and 3.