Seeed_QTouch.h

/*
    QTouch Library
    2014 Copyright (c) Seeed Technology Inc.  All right reserved.

    Author: ZhangKun & Loovee
    2013-3-20

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/
#ifndef __SEEED_QTOUCH_H__
#define __SEEED_QTOUCH_H__

#define ADDR_QTOUCH     0x1B                    // address of QTouch


#define QTOUCH_REG_CHIPID       0x00            // read chip id
#define QTOUCH_REG_VERSION      0x01            // Firmware Version
#define QTOUCH_REG_DETSTATUS    0X02            // detection status
#define QTOUCH_REG_KEYSTATUS    0X03            // key status

#define QTOUCH_REG_SIGMSBK0      0X04            // MSByte of KEY0
#define QTOUCH_REG_SIGLSBK0      0X05            // LSByte of KEY0

#define QTOUCH_REG_REFMSBK0		18
#define QTOUCH_REG_REFLSBK0		19

#define QTOUCH_REG_NTHRK0		32
#define QTOUCH_REG_AVEASK0		39
#define QTOUCH_REG_DIK0			46

#define QTOUCH_REG_LPMODE       0X36            // low power mode
#define QTOUCH_REG_MAXDURA      0X37            // max on duration
#define QTOUCH_REG_CALIBRATE    0X38            // calibrate
#define QTOUCH_REG_RESET        0X39            // reset


class SeeedQTouch {

  public:

    SeeedQTouch();
    unsigned char isTouch(int key);                     // if certain key touched, return 1 - touched, 0 untouched
    unsigned char getState();                           // return all key state, bit0 for key0, bit1 for key1....
    int touchNum();                                     // if no touch return -1, else return key number
    int setGroup(uint8_t key, uint8_t group);		// set key group or disable a key (group 255)
    int chipPresent();					// check if the chip is present												// check chip ID

    void setNTHRForKey(char nthr, char pin) {
        writeReg(QTOUCH_REG_NTHRK0 + pin, nthr);
    }
    int getSignalForKey(char pin) {
        return ((readReg(QTOUCH_REG_SIGMSBK0 + pin) << 8) + readReg(QTOUCH_REG_SIGLSBK0 + pin));
    }
    int getRefDataForKey(char pin) {
        return ((readReg(QTOUCH_REG_REFMSBK0 + pin) << 8) + readReg(QTOUCH_REG_REFLSBK0 + pin));
    }
    void setLowPowerMode(int val) {                     // set low power mode
        writeReg(QTOUCH_REG_LPMODE, val);
    }

    void reset() {                                      // reset
        writeReg(QTOUCH_REG_RESET, 0x55);               // write a non-zero value to reset
    }

    void setMaxDuration(char val) {                      // set maxim duration
        writeReg(QTOUCH_REG_MAXDURA, val);
    }

    void calibrate() {                                  // calibrate
        writeReg(QTOUCH_REG_CALIBRATE, 0x55);               // write a non-zero value to re-calibrate the device
    }

  private:

    unsigned char readReg(unsigned char addr_reg);                          // read register
    unsigned char writeReg(unsigned char addr_reg, unsigned char dta);      // write register
};

extern SeeedQTouch QTouch;
#endif