I inherited one of these bluetooth devices from my son who never was able to do anything with it. I don’t know the state it was left in, I am trying to figure out how to access it. Is there a way to return it to it’s factory settings?
Anyway I have it connected on a breadboard with only wires, 5V, Gnd. I am attempting to connect to it with windows and putty to see what the configuration is. It is properly installed in windows and windows told me it would be connected to com8. I changed the parameters for com8 to be baud=115200.
I open putty to com8 at 115200 and the bluetooth green light comes on, it is connected, but I can’t type in the terminal. Is there something I haven’t done? Is there an easier technique?
I glean that you are attempting to connect to the module wirelessly with a bluetooth transceiver on your computer. You say you cannot type in the terminal. I assume this means that you type a letter and do not see an echo in the terminal window. This is generally the default behavior in a serial terminal, unless you enable local echo in preferences. Nevertheless, characters you type are broadcast over the serial link. Have you read the command reference for this device?
It explains the entire command set, including how to enter command mode and reset default settings. If the any of the connection parameters (baud rate, parity, etc.) have been changed, you may be unable to establish serial communication with the device (despite being able to achieve a bluetooth connection), in which case, you would have to reset the module by toggling the reset pin according to the procedure outlined in section 3.4 of the user manual, and on Sparkfun’s product description page.
Note: The hardware reset pin of the RN-42 module is broken out on the bottom side of the board. This pin is mislabeled as ‘PIO6’, it is actually PIO4. Should you need to reset the Mate, pull this pin high upon power-up, and then toggle it 3 times.
Another consideration is that, by default, the RN-42 only allows remote configuration within 60 seconds of power up.
Most likely, if you establish a bluetooth connection at 115200 baud and type “$$$” within 60 seconds of power up, you will see “CMD” appear in the terminal, indicating you have connected to and entered command mode on the device.
Did you type “$$$” to get into command mode? If not, you need to visit the product page (http://www.sparkfun.com/products/10269), follow the link to the “RN-42 AT Command Set” document, and scan through some of it. I also found some of the comments at the bottom of the product page useful.