Another set of sample data for the EKG-EMG shield

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Hey,

thought I'd quickly share some beginnings of my work with the EKG-EMG shield.

I'm using the EKG-EMG shield (two of them, actually, but right now just one), my #Arduino Due, python with pyqtgraph and scipy for filtering and live data plotting.

The Due is running my own generic firmware (https://github.com/l-mb/GPIO_Platform), sampling my heart muscle activity at 400 Hz. (Electrodes on both wrists and the right ankle; the cables are too short, by the way.) The Olimex board is connected not as a shield, but via the A3 input directly. (As a shield, it'd block the A7 pin and SPI/I²C headers on the Due.)

The raw signal is very noisy (the amps are picking up the current the environment is inducing in my body; no joke - I always thought electrosmog was nonsense!), so I'm applying a Butterworth bandstop filter for the 45-55 Hz range. (Since making this image, I've switched to instead applying a 9th order 30 Hz lowpass filter, which works even better.)

I've never written code in Python from scratch, much less done any sort of GUI/Qt work, and my knowledge of signal processing mostly resolves around "cut that, paste there." The server side of this code will take a fair while to make prettier. And on the Due I surely needed a bit of time to adjust downwards from being used to multiple n GHz cores with tons of gigabytes of main memory ;-)

Also, working with PyCharm for the first time, rather than just vim. (With IdeaVim, of course.) Haven't yet decided whether I like it better, but it is for sure pretty.

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Something went wrong with the image I wanted to attach. Reposting.