Arduino & Adafruit Capacitive Sensor

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

 This is a library for the CAP1188 I2C/SPI 8-chan Capacitive Sensor

 Designed specifically to work with the CAP1188 sensor from Adafruit
 ----> https://www.adafruit.com/products/1602

 These sensors use I2C/SPI to communicate, 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
****************************************************/

1. include <Wire.h>
2. include <SPI.h>
3. include <Adafruit_CAP1188.h>

// Reset Pin is used for I2C or SPI

1. define CAP1188_RESET 9

// CS pin is used for software or hardware SPI //#define CAP1188_CS 10

// These are defined for software SPI, for hardware SPI, check your // board's SPI pins in the Arduino documentation //#define CAP1188_MOSI 11 //#define CAP1188_MISO 12 //#define CAP1188_CLK 13

// For I2C, connect SDA to your Arduino's SDA pin, SCL to SCL pin // On UNO/Duemilanove/etc, SDA == Analog 4, SCL == Analog 5 // On Leonardo/Micro, SDA == Digital 2, SCL == Digital 3 // On Mega/ADK/Due, SDA == Digital 20, SCL == Digital 21

// Use I2C, no reset pin! Adafruit_CAP1188 cap = Adafruit_CAP1188();

// Or...Use I2C, with reset pin //Adafruit_CAP1188 cap = Adafruit_CAP1188(CAP1188_RESET);

// Or... Hardware SPI, CS pin & reset pin // Adafruit_CAP1188 cap = Adafruit_CAP1188(CAP1188_CS, CAP1188_RESET);

// Or.. Software SPI: clock, miso, mosi, cs, reset //Adafruit_CAP1188 cap = Adafruit_CAP1188(CAP1188_CLK, CAP1188_MISO, CAP1188_MOSI, CAP1188_CS, CAP1188_RESET);

void setup() {

 Serial.begin(9600);
 while (!Serial) {
   ; // wait for serial port to connect. Needed for Leonardo/Micro only
 }
 Serial.println("CAP1188 test!");
 
 
 // Initialize the sensor, if using i2c you can pass in the i2c address
 // if (!cap.begin(0x28)) {
 if (!cap.begin()) {
   Serial.println("CAP1188 not found");
   while (1);
 }
 Serial.println("CAP1188 found!");
 //Decrease sensitivity a little - default is 0x2F (32x) per datasheet
 //cap.writeRegister(CAP1188_SENSITIVITY, 0x3F);  // 16x sensitivity
 //cap.writeRegister(CAP1188_SENSITIVITY, 0x4F);  // 8x  sensitivity
 //cap.writeRegister(CAP1188_SENSITIVITY, 0x5F);  // 4x  sensitivity
 cap.writeRegister(CAP1188_SENSITIVITY, 0x6F);  // 2x  sensitivity THIS SEEMS TO WORK THE BEST FOR 3.5" plate sensors
 //cap.writeRegister(CAP1188_SENSITIVITY, 0x7F);  // 1x  sensitivity
 //Serial.print("Sensitivity: 0x");
 //Serial.println(cap.readRegister(CAP1188_SENSITIVITY), HEX);

}

void loop() {

 uint8_t touched = cap.touched();
 if (touched == 0) {
   // No touch detected
   return;
 }
 
 for (uint8_t i=0; i<8; i++) {        // Check each bit, each bit represents 1 sensor
   if (touched & (1 << i)) {
     Serial.print("C"); Serial.print(i+1); Serial.print("\t");
   }
 }
 Serial.println();
 delay(50);

}