My colleague Ryan send me on a Tweet about SensoDuino, an app for Android Phones that allows you through the phone’s bluetooth to send sensor data from your phone; from gyroscope and accelerometer data to light, heat and humidity!; to your Arduino. As luck would have it I had borrowed a few items from work and had a Bluetooth module sitting right next to me on my coffee table. The problem being that the author recommends the cheaper RC05 bluetooth module and I had the rather expensive RN42 bluetooth module, adapted by Parallax into their 30086 module, which rather handily narrows down all of the various pins of the RN42 into seven outputs. There is very little information out there on connecting this module to the Arduino. So this post is to document process I went through to get the RN42 module to work with SensoDuino.
The wiring of the module is extremely easy to connect to the Arduino Pro as it has a jumper for 3.3v and 5v. The wiring is as so…
Arduino —> 30086 RN42
5v — > VIN
GND —> GND
0(RX) –> TX
1(TX) —> RX
That’s it, no need to knock the voltage down with combinations of resistors.
Uploading the sketch to the Arduino is standard, although as Hazam Bitar points out, you may need to disconnect the power from the bluetooth module as it will interfere with uploading a new sketch.
By default, the jumper settings on the Bluetooth module sets the baud rate to 9600, so you will need to change this in the sketch
Serial.begin(9600);
Or change the first jumper to off and it will run at 115200.
So that’s it. It will be interesting to see if I will be able to make my own app that can use the sensors in my phone to control whatever I wish without going through the rather excellent SensoDuino, but for those learning and wanting to prototype devices without working with complex wiring and badly documented components, then this is a brilliant app.
