The transmitter circuit uses Microchip`s dsPIC33FJ16GS504 for the analog-to-digital conversion of the input signals on two channels. The processed data on the dsPIC are then transmitted to the phone (for waveform display) via the LMX9838 bluetooth SPP module. The source codes for the bluetooth communication is based on Bluetooth Chat example from
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That example contains three java source files. And, I`ve completely copied the "DeviceListActivity. java", which is used for searching remote bluetooth devices. Then I`ve modified the "BluetoothChatService. java" to use only the RFCOMM Client functions, and used the well-known UUID " 00001101-0000-1000-8000-00805F9B34FB " for the Bluetooth RFCOMM/SPP. For the plotting of waveforms, I`m using SurfaceView object to draw on its canvas. This tutorial found on helps me a lot for this task: " How to use canvas in your android ". The rest of the job mainly involves porting of my previous Python S60 script to JAVA language. It was too painful on my side, because I had to convert a single script file to multiple java + xml source files! Nonetheless, it was a good experience for me on learning the Android SDK (JAVA programming). *The dsPIC I have used is most probably NOT the best choice for this project because of the many left unused peripherals (extra pins). But, this is the only part readily available in my bin and it has the fastest ADC (2 x 2MSps) among the chips I have. It`s almost a year now, and yet some people are still interested in this project (considered to be obsolete). So I`ve decided to place the source repository also on Google Code site. You can either Browse or use git to have your own local copy: See also the Changes, if you want also to learn on how to modify the code. I`ve started the first `commit` with a...
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