This is something I've been wanting to do for a long time, implementing Bluetooth connectivity for my Megasquirt ECU.
No more cables for tuning and data logging, I can even use my Android smartphone/tablet for data logging and digital gauge/dashes. The Android App is called Shadow Dash MS, free of charge from the EFI Analytics.
You can buy "off the self" devices that are plug and play, around $50-$100, but I've decided to take the DIY route which cost me $12!
There is a bit of work to do like adjust settings as well as some soldering.
1. The module needs to be jumpered temporarily so settings can be applied.
2. Use some paper to insulate pins 6, 7, 8 and 9 on the DB9 Male connector. And than solder a wire from pin 9 to V+ pad, this is next to the break-out pins.
3. An external +5V supply has to applied to the break-out pins.
So that completes most of the modifications needed, now on to software. I used Microsoft Hyper Terminal, which is available on Windows XP machines. You can download it below:
1. Connect the module to your serial port, or your USB-Serial adapter.
2. Open up Hyper Terminal and create a new connection. Select your serial connection's COM port., mine was COM4. The settings below should be applied.
3. To confirm that the connection is correct, quickly type in AT. It won't display what you've typed but it should display the response OK.
4. Open up Notepad and type the following AT+NAME(insert the name you want here), in my case I typed AT+NAMEomgpham.com . CUT all the text, go back to your Hyper Terminal window and click on "Paste to Host". You should than get a response saying OKsetname.
5. Next up we'll set the PIN Code. So back to Notepad and type in AT+PIN(insert your 4 digit pin here), eg. AT+PIN1234. CUT all the text, go back to your Hyper Terminal window and click on "Paste to Host". You should than get a response saying OKsetPIN.
6. Finally, we'll set the baud rate. By default it's 9600 but this needs to be set to 115200. So in Notepad you'll type AT+BAUD8, CUT all the text than go back to your Hyper Terminal window and click on "Paste to Host". You should than get a response saying OK115200.
The reason we have to cut and paste commands from Notepad is because Hyper Terminal needs commands to be typed completely in under a second. Stupid? Yes, but ah well.
So everything software wise is now done, this next part is optional and it involves removing the female DB9 connector which is used for applying settings. It's the connector that plugs into your computer's serial port.