Hi,
I’m having issues with the BT module getting to the configuration mode. The module blinks red 2/sec and continous to do so for “ever”. The device is also not visible to other devices.
What could be the issue?
Hi mrKnez,
How are you trying to configure the Bluetooth Mate? Do you have it connected to an Arduino like the [Hookup Guide demonstrates or are you connecting it directly to your computer via a USB to Serial bridge? The 2/sec blinking indicates the RN-42 is not in configuration mode but the configuration timer is running. You need to set the RN-42 into Command Mode by sending the proper command ($$$) to it via serial. This is covered in the Hookup Guide linked above.
The [Command Reference Guide will have the full list of AT commands for the RN-42 if you want to read more on that. If you are still having issues after attempting to configure the Bluetooth Mate following the Hookup Guide, please take a few photos of your board and the circuit you have it in.](https://cdn.sparkfun.com/assets/1/e/e/5/d/5217b297757b7fd3748b4567.pdf)](https://learn.sparkfun.com/tutorials/using-the-bluesmirf#hardware-hookup)
Thank you so much for your help. Still, I don’t seem to be able to make it work.
So I have uploaded the passthrough scetch on my device.
I opened the terminal and send the $$$ but I did not get any response.
What might I be missing here?
If you’re using the Arduino Serial Monitor to send ‘$$$’ it gets sent as a single string rather than three individual dollar signs.
There needs to be a small delay between each ‘$’ otherwise the bluetooth module thinks you’re sending data and ignores the request to drop into config mode. An analogue would be if you were to read the text ‘AAA’, you’d pronounce it ‘ahhh’ but if you were to read the text ‘A A A’ you’d say “triple A” or say the word ‘a’ three times.
The easiest way to get around this would be to not use the serial monitor since that only allows you to send text a line at a time. You might try Tera Term or Cool Term in place of the serial monitor as those transmit data a character at a time. I suspect things will go a lot smoother for you with a different terminal program.
Check out our guide on [Serial Terminal Basics and then use one of the programs listed in the guide and I think that should get you going. :-)](Serial Terminal Basics - SparkFun Learn)