Hello, I have a few of these xs3868 bluetooth audio modules that I used in some speaker systems I built for myself, but now one of my friends wants me to build him a custom speaker with a custom bluetooth device name and passcode. So I thought, ok, I read a little about programming with the AT commands but never tried it before, so I hooked up a board to 3.3 and gnd of the arduino like I usually do to check before soldering everything, my phone connected with no problem. So next I turned off my phone's bluetooth so it wouldn't mess with the chip while programming it and connected the rx and tx pins of the board to tx and rx respectively. I also made the following adjustments in the arduino serial interface that I remember reading somewhere: No Line Ending, and 9600 baud rate. Plugged in in to the tx and rx of the arduino board with at mega chip removed and had no luck getting any response from the chip, I switched baud rate to all of the different baud rates available with no success, the only effect the chip has on the serial interface is that when the power cord slipped and I plugged in back in with rx, tx and the usb cable still connected it output a few seemingly random characters while (I'm assuming) the chip was booting up, at 115200 baud rate the characters were a "u" with two dots over it and a combination lowercase "b" and "p" (for some reason I can't copy/paste it). It only outputs these characters when one of the power wires is reconnected after being disconnected (I have a bunch of these so if I fry one it's no big deal). I tried connecting my phone again after a while and it worked, checked the wires with my multimeter and both are connected and neither is shorted to any other pins and switching rx/tx does nothing to fix the problem either. I have a usb to serial coming in the mail soon hopefully but my friend was hoping this could be finished sooner than it would arrive so any help would be greatly appreciated. Edit: Is it possible that the module could have a rs232 interface, rather than a ttl interface? I've heard that arduino only uses ttl and that I'd need another adapter to get to rs232 since my computer doesn't have that kind of serial interface.