Datasheet

For most people, that's all you'll need! Our code keeps track of the 12 'bits' for each touch and has logic to let you

know when a contect is touched or released.

If you're feeling more advanced, you can see the 'raw' data from the chip. Basically, what it does it keep track of the

capacitance it sees with "counts". There's some baseline count number that depends on the temperature, humidity,

PCB, wire length etc. Where's a dramatic change in number, its considered that a person touched or released the wire.

Comment this "return" line to activate that mode:

Then reupload. Open up the serial console again - you'll see way more text

Each reading has 12 columns. One for each sensor, #0 to #11. There's two rows, one for the 'baseline' and one for the

current filtered data reading. When the current reading is within about 12 counts of the baseline, that's considered

untouched. When the reading is more than 12 counts smaller than the baseline, the chip reports a touch.

// comment out this line for detailed data from the sensor!

return;

https://learn.adafruit.com/adafruit-mpr121-12-key-capacitive-touch-sensor-breakout-

tutorial

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