I don't have an adapter to test with, but could you jumper the RX TX pins, power it up, open a serial terminal program (e.g. puTTY) and see if what you send out is looped back to you?
I don't have an adapter to test with, but could you jumper the RX TX pins, power it up, open a serial terminal program (e.g. puTTY) and see if what you send out is looped back to you?