Datasheet

Most people don't need raw data too much, but it can be handy if doing intense debugging. It can be helpful if you are

tweaking your sensors to get good responsivity.

Library Reference

Since the sensors use I2C, there's no pins to be defined during instantiation. You can just use:

Adafruit_MPR121 cap = Adafruit_MPR121();

When you initialize the sensor, pass in the I2C address. It can range from 0x5A (default) to 0x5D

cap.begin(0x5A)

begin() returns true if the sensor was found on the I2C bus, and false if not.

Touch detection

99% of users will be perfectly happy just querying what sensors are currentlt touched. You can read all at once with

cap.touched()

Which returns a 16 bit value. Each of the bottom 12 bits refers to one sensor. So if you want to test if the #4 is touched,

you can use

if (cap.touched() & (1 << 4)) { do something }

You can check its not touched with:

if (! (cap.touched() & (1 << 4)) ) { do something }

Raw Data

You can grab the current baseline and filtered data for each sensor with

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

tutorial

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