ads1x15.hpp

/*
 * Author: Marc Graham <marc@m2ag.net>
 * Copyright (c) 2015 Intel Corporation.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#pragma once

#include <iostream>
#include <string>

namespace mraa {class I2c;}

/*=========================================================================
    I2C ADDRESS/BITS
    -----------------------------------------------------------------------*/
#define ADS1X15_ADDRESS                 (0x48)    // 1001 000 (ADDR = GND)
/*=========================================================================*/


/*=========================================================================
    POINTER REGISTER
    -----------------------------------------------------------------------*/
#define ADS1X15_REG_POINTER_MASK        (0x03)
#define ADS1X15_REG_POINTER_CONVERT     (0x00)
#define ADS1X15_REG_POINTER_CONFIG      (0x01)
#define ADS1X15_REG_POINTER_LOWTHRESH   (0x02)
#define ADS1X15_REG_POINTER_HITHRESH    (0x03)
/*=========================================================================*/

/*=========================================================================
    CONFIG REGISTER

    -----------------------------------------------------------------------*/
#define ADS1X15_OS_MASK      (0x8000)
#define ADS1X15_OS_SINGLE    (0x8000)  // Write: Set to start a single-conversion
#define ADS1X15_OS_BUSY      (0x0000)  // Read: Bit = 0 when conversion is in progress
#define ADS1X15_OS_NOTBUSY   (0x8000)  // Read: Bit = 1 when device is not performing a conversion

#define ADS1X15_MUX_MASK     (0x7000)
#define ADS1X15_MUX_DIFF_0_1 (0x0000)  // Differential P = AIN0, N = AIN1 (default)
#define ADS1X15_MUX_DIFF_0_3 (0x1000)  // Differential P = AIN0, N = AIN3
#define ADS1X15_MUX_DIFF_1_3 (0x2000)  // Differential P = AIN1, N = AIN3
#define ADS1X15_MUX_DIFF_2_3 (0x3000)  // Differential P = AIN2, N = AIN3
#define ADS1X15_MUX_SINGLE_0 (0x4000)  // Single-ended AIN0
#define ADS1X15_MUX_SINGLE_1 (0x5000)  // Single-ended AIN1
#define ADS1X15_MUX_SINGLE_2 (0x6000)  // Single-ended AIN2
#define ADS1X15_MUX_SINGLE_3 (0x7000)  // Single-ended AIN3

#define ADS1X15_PGA_MASK     (0x0E00)
#define ADS1X15_PGA_6_144V   (0x0000)  // +/-6.144V range = Gain 2/3
#define ADS1X15_PGA_4_096V   (0x0200)  // +/-4.096V range = Gain 1
#define ADS1X15_PGA_2_048V   (0x0400)  // +/-2.048V range = Gain 2 (default)
#define ADS1X15_PGA_1_024V   (0x0600)  // +/-1.024V range = Gain 4
#define ADS1X15_PGA_0_512V   (0x0800)  // +/-0.512V range = Gain 8
#define ADS1X15_PGA_0_256V   (0x0A00)  // +/-0.256V range = Gain 16

#define ADS1X15_MODE_MASK    (0x0100)
#define ADS1X15_MODE_CONTIN  (0x0000)  // Continuous conversion mode
#define ADS1X15_MODE_SINGLE  (0x0100)  // Power-down single-shot mode (default)

#define ADS1X15_DR_MASK      (0x00E0)

#define ADS1X15_CMODE_MASK   (0x0010)
#define ADS1X15_CMODE_TRAD   (0x0000)  // Traditional comparator with hysteresis (default)
#define ADS1X15_CMODE_WINDOW (0x0010)  // Window comparator

#define ADS1X15_CPOL_MASK    (0x0008)
#define ADS1X15_CPOL_ACTVLOW (0x0000)  // ALERT/RDY pin is low when active (default)
#define ADS1X15_CPOL_ACTVHI  (0x0008)  // ALERT/RDY pin is high when active

#define ADS1X15_CLAT_MASK    (0x0400)  // Determines if ALERT/RDY pin latches once asserted
#define ADS1X15_CLAT_NONLAT  (0x0000)  // Non-latching comparator (default)
#define ADS1X15_CLAT_LATCH   (0x0400)  // Latching comparator

#define ADS1X15_CQUE_MASK    (0x0003)
/* This wouldn't compile for the python wrapper. with these in for some reason.
#define ADS1X15_CQUE_1CONV   (0x0000)  // Assert ALERT/RDY after one conversions
#define ADS1X15_CQUE_2CONV     (0x0001)  // Assert ALERT/RDY after two conversions
#define ADS1X15_CQUE_4CONV     (0x0002)  // Assert ALERT/RDY after four conversions
#define ADS1X15_CQUE_NONE      (0x0003)  // Disable the comparator and put ALERT/RDY in high state (default)
*/
/*=========================================================================*/

namespace upm {
    class ADS1X15 {

        public:

            typedef enum ADSGAIN {
              GAIN_TWOTHIRDS    = ADS1X15_PGA_6_144V,
              GAIN_ONE          = ADS1X15_PGA_4_096V,
              GAIN_TWO          = ADS1X15_PGA_2_048V,
              GAIN_FOUR         = ADS1X15_PGA_1_024V,
              GAIN_EIGHT        = ADS1X15_PGA_0_512V,
              GAIN_SIXTEEN      = ADS1X15_PGA_0_256V
            } ADSGAIN ;

            typedef enum ADSMUXMODE {
              DIFF_0_1        = ADS1X15_MUX_DIFF_0_1,  // Differential P = AIN0, N = AIN1 (default)
              DIFF_0_3        = ADS1X15_MUX_DIFF_0_3,  // Differential P = AIN0, N = AIN3
              DIFF_1_3        = ADS1X15_MUX_DIFF_1_3,  // Differential P = AIN1, N = AIN3
              DIFF_2_3        = ADS1X15_MUX_DIFF_2_3,  // Differential P = AIN2, N = AIN3
              SINGLE_0        = ADS1X15_MUX_SINGLE_0,  // Single-ended AIN0
              SINGLE_1        = ADS1X15_MUX_SINGLE_1,  // Single-ended AIN1
              SINGLE_2        = ADS1X15_MUX_SINGLE_2,  // Single-ended AIN2
              SINGLE_3        = ADS1X15_MUX_SINGLE_3   // Single-ended AIN3
            } ADSMUXMODE;

            typedef enum ADSCOMP {
               CQUE_1CONV      = 0x0000,    // Assert ALERT/RDY after one conversions
               CQUE_2CONV      = 0x0001,    // Assert ALERT/RDY after two conversions
               CQUE_4CONV      = 0x0002,    // Assert ALERT/RDY after four conversions
               CQUE_NONE       = 0x0003      // Disable the comparator and put ALERT/RDY in high state (default)
            } ADSCOMP;

            typedef enum ADSTHRESH {
                THRESH_LOW      = ADS1X15_REG_POINTER_LOWTHRESH,
                THRESH_HIGH     = ADS1X15_REG_POINTER_HITHRESH,
                CONVERSION_RDY  = 0x04,
                THRESH_DEFAULT  = 0x05

            } ADSTHRESH;

            typedef enum ADSSAMPLERATE {
               SPS_DEFAULT     = 0x0080
            } ADSSAMPLERATE;

            ADS1X15(int bus, uint8_t address);

            virtual ~ADS1X15 ();

            std::string name()
            {
                return m_name;
            }

            float getLastSample(int reg = ADS1X15_REG_POINTER_CONVERT);

            float getSample(ADSMUXMODE mode = ADS1X15::DIFF_0_1);

            ADSGAIN getGain(){
                return  (ADSGAIN)(m_config_reg & ADS1X15_PGA_MASK);
            }

            void setGain(ADSGAIN gain = ADS1X15::GAIN_TWO);

            ADSSAMPLERATE getSPS(void){
                return (ADSSAMPLERATE)(m_config_reg & ADS1X15_DR_MASK);
            }

            virtual void setSPS(ADSSAMPLERATE rate);

            bool getCompMode(void){
                return (bool)(m_config_reg & ADS1X15_CMODE_MASK);
            }

            void setCompMode(bool mode = false);

            bool getCompPol(void){
                return (bool)(m_config_reg & ADS1X15_CPOL_MASK);
            }

            void setCompPol(bool mode = false);

            bool getCompLatch(void){
                return (bool)(m_config_reg & ADS1X15_CLAT_MASK);
            }

            void setCompLatch(bool mode = false);

            ADSCOMP getCompQue(void){
                return (ADSCOMP)(m_config_reg & ADS1X15_CQUE_MASK);
            }

            void setCompQue(ADSCOMP mode = ADS1X15::CQUE_NONE);

            bool getContinuous(void){
                return !(bool)(m_config_reg & ADS1X15_MODE_MASK);
            }

            void setContinuous(bool mode = false);

            float getThresh(ADSTHRESH reg = THRESH_DEFAULT);

            void setThresh(ADSTHRESH reg = THRESH_DEFAULT , float value = 0.0);

        protected:
            std::string m_name;
            float m_conversionDelay;
            uint8_t m_bitShift;
            uint16_t m_config_reg;
            //Must be overridden in subclass for proper values.
            virtual float getMultiplier(void) = 0;
            //Must be overridden in subclass for proper values.
            virtual void setDelay(void) = 0;
            void getCurrentConfig();
            void updateConfigRegister(uint16_t update, bool read = false);
            uint16_t swapWord(uint16_t value);

            mraa::I2c* i2c;

    };}