I can't answer your question, but I'll pose one to you
You mention an RS232 adaptor / cable. But if you Google for cables for these, all you get are USB ones. However from the images, these seem to be two types: one with a mini-USB connector at the phone end, the other with what looks like some kind of bespoke clip
Do you have any cables with it? Looks like you may have to try and work out which is the correct one