RN42 (Bluetooth)

A project log for MagiLog: Open Automotive Datalogging

Developing a full featured datalogger on the cheap

nigelNigel 04/11/2018 at 07:180 Comments
Getting the RN42 up and running was surprisingly simple. Just hooked up a serial adapter and I was able to pair the device with my computer without trouble. From there we just open up two serial terminals to verify that the communication is working. There was one odd quirk with how the Bluetooth COM port worked. While the datasheet said to use the “outgoing” labelled COM port I was only able to get the device to communicate using the “incoming” port. Once everything was set up I was free to send as much gibberish between serial terminals as I wanted.

There are some newer options from Microchip that have support to up to Bluetooth 4.2, but I'm not sure if I'll need that much throughput. I'll try to push the RN42 as far as I can and upgrade if I need to down the road.

I’m almost finished with all the peripherals now. I just have the OBD/CAN system left but I need to wait on a few components to get in before I can get the test bench all set up. I’ll start filling in the details on what I’m going to do with the XMega and the FPGA while I wait. It looks like I’ll be getting down to coding by this time next week.