/*********************************************************

This is a library for the MPR121 12-channel Capacitive touch sensor

Designed specifically to work with the MPR121 Breakout in the Adafruit shop

----> https://www.adafruit.com/products/

These sensors use I2C communicate, at least 2 pins are required

to interface

Adafruit invests time and resources providing this open source code,

please support Adafruit and open-source hardware by purchasing

products from Adafruit!

Written by Limor Fried/Ladyada for Adafruit Industries.

BSD license, all text above must be included in any redistribution

**********************************************************/

#include <Wire.h>

#include "Adafruit_MPR121.h"

// You can have up to 4 on one i2c bus but one is enough for testing!

Adafruit_MPR121 cap = Adafruit_MPR121();

// Keeps track of the last pins touched

// so we know when buttons are 'released'

uint16_t lasttouched = 0;

uint16_t currtouched = 0;

void setup() {

while (!Serial); // needed to keep leonardo/micro from starting too fast!

Serial.begin(9600);

Serial.println("Adafruit MPR121 Capacitive Touch sensor test");

// Default address is 0x5A, if tied to 3.3V its 0x5B

// If tied to SDA its 0x5C and if SCL then 0x5D

if (!cap.begin(0x5A)) {

Serial.println("MPR121 not found, check wiring?");

while (1);

}

Serial.println("MPR121 found!");

}

void loop() {

// Get the currently touched pads

currtouched = cap.touched();

for (uint8_t i=0; i<12; i++) {

// it if *is* touched and *wasnt* touched before, alert!

if ((currtouched & _BV(i)) && !(lasttouched & _BV(i)) ) {

Serial.print(i); Serial.println(" touched");

}

// if it *was* touched and now *isnt*, alert!

if (!(currtouched & _BV(i)) && (lasttouched & _BV(i)) ) {

Serial.print(i); Serial.println(" released");

}

}

// reset our state

lasttouched = currtouched;

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

return;

// debugging info, what

Serial.print("\t\t\t\t\t\t\t\t\t\t\t\t\t 0x"); Serial.println(cap.touched(), HEX);

Serial.print("Filt: ");

for (uint8_t i=0; i<12; i++) {

Serial.print(cap.filteredData(i)); Serial.print("\t");

}

Serial.println();

Serial.print("Base: ");

for (uint8_t i=0; i<12; i++) {

Serial.print(cap.baselineData(i)); Serial.print("\t");

}

Serial.println();

// put a delay so it isn't overwhelming

delay(100);

}