Jorge Troncoso / Sensor2

JT

Adafruit_ADS1015.cpp@0:4096be81b17f, 2018-01-04 (annotated)

Committer:
jortronm2
Date:
Thu Jan 04 03:39:28 2018 +0000
Revision:
0:4096be81b17f
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jortronm2 0:4096be81b17f 1 /**************************************************************************/
jortronm2 0:4096be81b17f 2 /*!
jortronm2 0:4096be81b17f 3 @file Adafruit_ADS1015.cpp
jortronm2 0:4096be81b17f 4 @author K.Townsend (Adafruit Industries)
jortronm2 0:4096be81b17f 5 @license BSD (see LICENSE.txt)
jortronm2 0:4096be81b17f 6
jortronm2 0:4096be81b17f 7 Ported to mbed by Arve Seljebu - arve0.github.io
jortronm2 0:4096be81b17f 8
jortronm2 0:4096be81b17f 9 Driver for the ADS1015/ADS1115 ADC
jortronm2 0:4096be81b17f 10
jortronm2 0:4096be81b17f 11 This is a library for the Adafruit MPL115A2 breakout
jortronm2 0:4096be81b17f 12 ----> https://www.adafruit.com/products/1083
jortronm2 0:4096be81b17f 13
jortronm2 0:4096be81b17f 14 Adafruit invests time and resources providing this open source code,
jortronm2 0:4096be81b17f 15 please support Adafruit and open-source hardware by purchasing
jortronm2 0:4096be81b17f 16 products from Adafruit!
jortronm2 0:4096be81b17f 17
jortronm2 0:4096be81b17f 18 @section HISTORY
jortronm2 0:4096be81b17f 19
jortronm2 0:4096be81b17f 20 v1.0 - First release
jortronm2 0:4096be81b17f 21 v1.1.1 - Ported to mbed
jortronm2 0:4096be81b17f 22 */
jortronm2 0:4096be81b17f 23 /**************************************************************************/
jortronm2 0:4096be81b17f 24
jortronm2 0:4096be81b17f 25 #include <mbed.h>
jortronm2 0:4096be81b17f 26 #include "Adafruit_ADS1015.h"
jortronm2 0:4096be81b17f 27
jortronm2 0:4096be81b17f 28 /**************************************************************************/
jortronm2 0:4096be81b17f 29 /*!
jortronm2 0:4096be81b17f 30 @brief Writes 16-bits to the specified destination register
jortronm2 0:4096be81b17f 31 */
jortronm2 0:4096be81b17f 32 /**************************************************************************/
jortronm2 0:4096be81b17f 33 void Adafruit_ADS1015::writeRegister(uint8_t i2cAddress, uint8_t reg, uint16_t value)
jortronm2 0:4096be81b17f 34 {
jortronm2 0:4096be81b17f 35 char cmd[3];
jortronm2 0:4096be81b17f 36 cmd[0] = (char)reg;
jortronm2 0:4096be81b17f 37 cmd[1] = (char)(value>>8);
jortronm2 0:4096be81b17f 38 cmd[2] = (char)(value & 0xFF);
jortronm2 0:4096be81b17f 39 m_i2c->write(i2cAddress, cmd, 3);
jortronm2 0:4096be81b17f 40 }
jortronm2 0:4096be81b17f 41
jortronm2 0:4096be81b17f 42 /**************************************************************************/
jortronm2 0:4096be81b17f 43 /*!
jortronm2 0:4096be81b17f 44 @brief Reads 16-bits from the specified register
jortronm2 0:4096be81b17f 45 */
jortronm2 0:4096be81b17f 46 /**************************************************************************/
jortronm2 0:4096be81b17f 47 uint16_t Adafruit_ADS1015::readRegister(uint8_t i2cAddress, uint8_t reg)
jortronm2 0:4096be81b17f 48 {
jortronm2 0:4096be81b17f 49 char data[2];
jortronm2 0:4096be81b17f 50 data[0] = reg; // temporary use this to send address to conversion register
jortronm2 0:4096be81b17f 51 m_i2c->write(i2cAddress, data, 1);
jortronm2 0:4096be81b17f 52 m_i2c->read(i2cAddress, data, 2);
jortronm2 0:4096be81b17f 53 return (data[0] << 8 | data [1]);
jortronm2 0:4096be81b17f 54 }
jortronm2 0:4096be81b17f 55
jortronm2 0:4096be81b17f 56 /**************************************************************************/
jortronm2 0:4096be81b17f 57 /*!
jortronm2 0:4096be81b17f 58 @brief Instantiates a new ADS1015 class w/appropriate properties
jortronm2 0:4096be81b17f 59 */
jortronm2 0:4096be81b17f 60 /**************************************************************************/
jortronm2 0:4096be81b17f 61 Adafruit_ADS1015::Adafruit_ADS1015(I2C* i2c, uint8_t i2cAddress)
jortronm2 0:4096be81b17f 62 {
jortronm2 0:4096be81b17f 63 // shift 7 bit address 1 left: read expects 8 bit address, see I2C.h
jortronm2 0:4096be81b17f 64 m_i2cAddress = i2cAddress << 1;
jortronm2 0:4096be81b17f 65 m_conversionDelay = ADS1015_CONVERSIONDELAY;
jortronm2 0:4096be81b17f 66 m_bitShift = 4;
jortronm2 0:4096be81b17f 67 m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */
jortronm2 0:4096be81b17f 68 m_i2c = i2c;
jortronm2 0:4096be81b17f 69 }
jortronm2 0:4096be81b17f 70
jortronm2 0:4096be81b17f 71 /**************************************************************************/
jortronm2 0:4096be81b17f 72 /*!
jortronm2 0:4096be81b17f 73 @brief Instantiates a new ADS1115 class w/appropriate properties
jortronm2 0:4096be81b17f 74 */
jortronm2 0:4096be81b17f 75 /**************************************************************************/
jortronm2 0:4096be81b17f 76 Adafruit_ADS1115::Adafruit_ADS1115(I2C* i2c, uint8_t i2cAddress)
jortronm2 0:4096be81b17f 77 {
jortronm2 0:4096be81b17f 78 // shift 7 bit address 1 left: read expects 8 bit address, see mbed's I2C.h
jortronm2 0:4096be81b17f 79 m_i2cAddress = i2cAddress << 1;
jortronm2 0:4096be81b17f 80 m_conversionDelay = ADS1115_CONVERSIONDELAY;
jortronm2 0:4096be81b17f 81 m_bitShift = 0;
jortronm2 0:4096be81b17f 82 m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */
jortronm2 0:4096be81b17f 83 m_i2c = i2c;
jortronm2 0:4096be81b17f 84 }
jortronm2 0:4096be81b17f 85
jortronm2 0:4096be81b17f 86 /**************************************************************************/
jortronm2 0:4096be81b17f 87 /*!
jortronm2 0:4096be81b17f 88 @brief Sets the gain and input voltage range
jortronm2 0:4096be81b17f 89 */
jortronm2 0:4096be81b17f 90 /**************************************************************************/
jortronm2 0:4096be81b17f 91 void Adafruit_ADS1015::setGain(adsGain_t gain)
jortronm2 0:4096be81b17f 92 {
jortronm2 0:4096be81b17f 93 m_gain = gain;
jortronm2 0:4096be81b17f 94 }
jortronm2 0:4096be81b17f 95
jortronm2 0:4096be81b17f 96 /**************************************************************************/
jortronm2 0:4096be81b17f 97 /*!
jortronm2 0:4096be81b17f 98 @brief Gets a gain and input voltage range
jortronm2 0:4096be81b17f 99 */
jortronm2 0:4096be81b17f 100 /**************************************************************************/
jortronm2 0:4096be81b17f 101 adsGain_t Adafruit_ADS1015::getGain()
jortronm2 0:4096be81b17f 102 {
jortronm2 0:4096be81b17f 103 return m_gain;
jortronm2 0:4096be81b17f 104 }
jortronm2 0:4096be81b17f 105
jortronm2 0:4096be81b17f 106 /**************************************************************************/
jortronm2 0:4096be81b17f 107 /*!
jortronm2 0:4096be81b17f 108 @brief Gets a single-ended ADC reading from the specified channel
jortronm2 0:4096be81b17f 109 */
jortronm2 0:4096be81b17f 110 /**************************************************************************/
jortronm2 0:4096be81b17f 111 uint16_t Adafruit_ADS1015::readADC_SingleEnded(uint8_t channel)
jortronm2 0:4096be81b17f 112 {
jortronm2 0:4096be81b17f 113 if (channel > 3) {
jortronm2 0:4096be81b17f 114 return 0;
jortronm2 0:4096be81b17f 115 }
jortronm2 0:4096be81b17f 116
jortronm2 0:4096be81b17f 117 // Start with default values
jortronm2 0:4096be81b17f 118 uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val)
jortronm2 0:4096be81b17f 119 ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val)
jortronm2 0:4096be81b17f 120 ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val)
jortronm2 0:4096be81b17f 121 ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val)
jortronm2 0:4096be81b17f 122 ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default)
jortronm2 0:4096be81b17f 123 ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default)
jortronm2 0:4096be81b17f 124
jortronm2 0:4096be81b17f 125 // Set PGA/voltage range
jortronm2 0:4096be81b17f 126 config |= m_gain;
jortronm2 0:4096be81b17f 127
jortronm2 0:4096be81b17f 128 // Set single-ended input channel
jortronm2 0:4096be81b17f 129 switch (channel) {
jortronm2 0:4096be81b17f 130 case (0):
jortronm2 0:4096be81b17f 131 config |= ADS1015_REG_CONFIG_MUX_SINGLE_0;
jortronm2 0:4096be81b17f 132 break;
jortronm2 0:4096be81b17f 133 case (1):
jortronm2 0:4096be81b17f 134 config |= ADS1015_REG_CONFIG_MUX_SINGLE_1;
jortronm2 0:4096be81b17f 135 break;
jortronm2 0:4096be81b17f 136 case (2):
jortronm2 0:4096be81b17f 137 config |= ADS1015_REG_CONFIG_MUX_SINGLE_2;
jortronm2 0:4096be81b17f 138 break;
jortronm2 0:4096be81b17f 139 case (3):
jortronm2 0:4096be81b17f 140 config |= ADS1015_REG_CONFIG_MUX_SINGLE_3;
jortronm2 0:4096be81b17f 141 break;
jortronm2 0:4096be81b17f 142 }
jortronm2 0:4096be81b17f 143
jortronm2 0:4096be81b17f 144 // Set 'start single-conversion' bit
jortronm2 0:4096be81b17f 145 config |= ADS1015_REG_CONFIG_OS_SINGLE;
jortronm2 0:4096be81b17f 146
jortronm2 0:4096be81b17f 147 // Write config register to the ADC
jortronm2 0:4096be81b17f 148 writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config);
jortronm2 0:4096be81b17f 149
jortronm2 0:4096be81b17f 150 // Wait for the conversion to complete
jortronm2 0:4096be81b17f 151 wait_ms(m_conversionDelay);
jortronm2 0:4096be81b17f 152
jortronm2 0:4096be81b17f 153 // Read the conversion results
jortronm2 0:4096be81b17f 154 // Shift 12-bit results right 4 bits for the ADS1015
jortronm2 0:4096be81b17f 155 return readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift;
jortronm2 0:4096be81b17f 156 }
jortronm2 0:4096be81b17f 157
jortronm2 0:4096be81b17f 158 /**************************************************************************/
jortronm2 0:4096be81b17f 159 /*!
jortronm2 0:4096be81b17f 160 @brief Reads the conversion results, measuring the voltage
jortronm2 0:4096be81b17f 161 difference between the P (AIN0) and N (AIN1) input. Generates
jortronm2 0:4096be81b17f 162 a signed value since the difference can be either
jortronm2 0:4096be81b17f 163 positive or negative.
jortronm2 0:4096be81b17f 164 */
jortronm2 0:4096be81b17f 165 /**************************************************************************/
jortronm2 0:4096be81b17f 166 int16_t Adafruit_ADS1015::readADC_Differential_0_1()
jortronm2 0:4096be81b17f 167 {
jortronm2 0:4096be81b17f 168 // Start with default values
jortronm2 0:4096be81b17f 169 uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val)
jortronm2 0:4096be81b17f 170 ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val)
jortronm2 0:4096be81b17f 171 ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val)
jortronm2 0:4096be81b17f 172 ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val)
jortronm2 0:4096be81b17f 173 ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default)
jortronm2 0:4096be81b17f 174 ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default)
jortronm2 0:4096be81b17f 175
jortronm2 0:4096be81b17f 176 // Set PGA/voltage range
jortronm2 0:4096be81b17f 177 config |= m_gain;
jortronm2 0:4096be81b17f 178
jortronm2 0:4096be81b17f 179 // Set channels
jortronm2 0:4096be81b17f 180 config |= ADS1015_REG_CONFIG_MUX_DIFF_0_1; // AIN0 = P, AIN1 = N
jortronm2 0:4096be81b17f 181
jortronm2 0:4096be81b17f 182 // Set 'start single-conversion' bit
jortronm2 0:4096be81b17f 183 config |= ADS1015_REG_CONFIG_OS_SINGLE;
jortronm2 0:4096be81b17f 184
jortronm2 0:4096be81b17f 185 // Write config register to the ADC
jortronm2 0:4096be81b17f 186 writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config);
jortronm2 0:4096be81b17f 187
jortronm2 0:4096be81b17f 188 // Wait for the conversion to complete
jortronm2 0:4096be81b17f 189 wait_ms(m_conversionDelay);
jortronm2 0:4096be81b17f 190
jortronm2 0:4096be81b17f 191 // Read the conversion results
jortronm2 0:4096be81b17f 192 uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift;
jortronm2 0:4096be81b17f 193 if (m_bitShift == 0) {
jortronm2 0:4096be81b17f 194 return (int16_t)res;
jortronm2 0:4096be81b17f 195 } else {
jortronm2 0:4096be81b17f 196 // Shift 12-bit results right 4 bits for the ADS1015,
jortronm2 0:4096be81b17f 197 // making sure we keep the sign bit intact
jortronm2 0:4096be81b17f 198 if (res > 0x07FF) {
jortronm2 0:4096be81b17f 199 // negative number - extend the sign to 16th bit
jortronm2 0:4096be81b17f 200 res |= 0xF000;
jortronm2 0:4096be81b17f 201 }
jortronm2 0:4096be81b17f 202 return (int16_t)res;
jortronm2 0:4096be81b17f 203 }
jortronm2 0:4096be81b17f 204 }
jortronm2 0:4096be81b17f 205
jortronm2 0:4096be81b17f 206 /**************************************************************************/
jortronm2 0:4096be81b17f 207 /*!
jortronm2 0:4096be81b17f 208 @brief Reads the conversion results, measuring the voltage
jortronm2 0:4096be81b17f 209 difference between the P (AIN2) and N (AIN3) input. Generates
jortronm2 0:4096be81b17f 210 a signed value since the difference can be either
jortronm2 0:4096be81b17f 211 positive or negative.
jortronm2 0:4096be81b17f 212 */
jortronm2 0:4096be81b17f 213 /**************************************************************************/
jortronm2 0:4096be81b17f 214 int16_t Adafruit_ADS1015::readADC_Differential_2_3()
jortronm2 0:4096be81b17f 215 {
jortronm2 0:4096be81b17f 216 // Start with default values
jortronm2 0:4096be81b17f 217 uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val)
jortronm2 0:4096be81b17f 218 ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val)
jortronm2 0:4096be81b17f 219 ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val)
jortronm2 0:4096be81b17f 220 ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val)
jortronm2 0:4096be81b17f 221 ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default)
jortronm2 0:4096be81b17f 222 ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default)
jortronm2 0:4096be81b17f 223
jortronm2 0:4096be81b17f 224 // Set PGA/voltage range
jortronm2 0:4096be81b17f 225 config |= m_gain;
jortronm2 0:4096be81b17f 226
jortronm2 0:4096be81b17f 227 // Set channels
jortronm2 0:4096be81b17f 228 config |= ADS1015_REG_CONFIG_MUX_DIFF_2_3; // AIN2 = P, AIN3 = N
jortronm2 0:4096be81b17f 229
jortronm2 0:4096be81b17f 230 // Set 'start single-conversion' bit
jortronm2 0:4096be81b17f 231 config |= ADS1015_REG_CONFIG_OS_SINGLE;
jortronm2 0:4096be81b17f 232
jortronm2 0:4096be81b17f 233 // Write config register to the ADC
jortronm2 0:4096be81b17f 234 writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config);
jortronm2 0:4096be81b17f 235
jortronm2 0:4096be81b17f 236 // Wait for the conversion to complete
jortronm2 0:4096be81b17f 237 wait_ms(m_conversionDelay);
jortronm2 0:4096be81b17f 238
jortronm2 0:4096be81b17f 239 // Read the conversion results
jortronm2 0:4096be81b17f 240 uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift;
jortronm2 0:4096be81b17f 241 if (m_bitShift == 0) {
jortronm2 0:4096be81b17f 242 return (int16_t)res;
jortronm2 0:4096be81b17f 243 } else {
jortronm2 0:4096be81b17f 244 // Shift 12-bit results right 4 bits for the ADS1015,
jortronm2 0:4096be81b17f 245 // making sure we keep the sign bit intact
jortronm2 0:4096be81b17f 246 if (res > 0x07FF) {
jortronm2 0:4096be81b17f 247 // negative number - extend the sign to 16th bit
jortronm2 0:4096be81b17f 248 res |= 0xF000;
jortronm2 0:4096be81b17f 249 }
jortronm2 0:4096be81b17f 250 return (int16_t)res;
jortronm2 0:4096be81b17f 251 }
jortronm2 0:4096be81b17f 252 }
jortronm2 0:4096be81b17f 253
jortronm2 0:4096be81b17f 254 /**************************************************************************/
jortronm2 0:4096be81b17f 255 /*!
jortronm2 0:4096be81b17f 256 @brief Sets up the comparator to operate in basic mode, causing the
jortronm2 0:4096be81b17f 257 ALERT/RDY pin to assert (go from high to low) when the ADC
jortronm2 0:4096be81b17f 258 value exceeds the specified threshold.
jortronm2 0:4096be81b17f 259
jortronm2 0:4096be81b17f 260 This will also set the ADC in continuous conversion mode.
jortronm2 0:4096be81b17f 261 */
jortronm2 0:4096be81b17f 262 /**************************************************************************/
jortronm2 0:4096be81b17f 263 void Adafruit_ADS1015::startComparator_SingleEnded(uint8_t channel, int16_t threshold)
jortronm2 0:4096be81b17f 264 {
jortronm2 0:4096be81b17f 265 // Start with default values
jortronm2 0:4096be81b17f 266 uint16_t config = ADS1015_REG_CONFIG_CQUE_1CONV | // Comparator enabled and asserts on 1 match
jortronm2 0:4096be81b17f 267 ADS1015_REG_CONFIG_CLAT_LATCH | // Latching mode
jortronm2 0:4096be81b17f 268 ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val)
jortronm2 0:4096be81b17f 269 ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val)
jortronm2 0:4096be81b17f 270 ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default)
jortronm2 0:4096be81b17f 271 ADS1015_REG_CONFIG_MODE_CONTIN | // Continuous conversion mode
jortronm2 0:4096be81b17f 272 ADS1015_REG_CONFIG_MODE_CONTIN; // Continuous conversion mode
jortronm2 0:4096be81b17f 273
jortronm2 0:4096be81b17f 274 // Set PGA/voltage range
jortronm2 0:4096be81b17f 275 config |= m_gain;
jortronm2 0:4096be81b17f 276
jortronm2 0:4096be81b17f 277 // Set single-ended input channel
jortronm2 0:4096be81b17f 278 switch (channel) {
jortronm2 0:4096be81b17f 279 case (0):
jortronm2 0:4096be81b17f 280 config |= ADS1015_REG_CONFIG_MUX_SINGLE_0;
jortronm2 0:4096be81b17f 281 break;
jortronm2 0:4096be81b17f 282 case (1):
jortronm2 0:4096be81b17f 283 config |= ADS1015_REG_CONFIG_MUX_SINGLE_1;
jortronm2 0:4096be81b17f 284 break;
jortronm2 0:4096be81b17f 285 case (2):
jortronm2 0:4096be81b17f 286 config |= ADS1015_REG_CONFIG_MUX_SINGLE_2;
jortronm2 0:4096be81b17f 287 break;
jortronm2 0:4096be81b17f 288 case (3):
jortronm2 0:4096be81b17f 289 config |= ADS1015_REG_CONFIG_MUX_SINGLE_3;
jortronm2 0:4096be81b17f 290 break;
jortronm2 0:4096be81b17f 291 }
jortronm2 0:4096be81b17f 292
jortronm2 0:4096be81b17f 293 // Set the high threshold register
jortronm2 0:4096be81b17f 294 // Shift 12-bit results left 4 bits for the ADS1015
jortronm2 0:4096be81b17f 295 writeRegister(m_i2cAddress, ADS1015_REG_POINTER_HITHRESH, threshold << m_bitShift);
jortronm2 0:4096be81b17f 296
jortronm2 0:4096be81b17f 297 // Write config register to the ADC
jortronm2 0:4096be81b17f 298 writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config);
jortronm2 0:4096be81b17f 299 }
jortronm2 0:4096be81b17f 300
jortronm2 0:4096be81b17f 301 /**************************************************************************/
jortronm2 0:4096be81b17f 302 /*!
jortronm2 0:4096be81b17f 303 @brief In order to clear the comparator, we need to read the
jortronm2 0:4096be81b17f 304 conversion results. This function reads the last conversion
jortronm2 0:4096be81b17f 305 results without changing the config value.
jortronm2 0:4096be81b17f 306 */
jortronm2 0:4096be81b17f 307 /**************************************************************************/
jortronm2 0:4096be81b17f 308 int16_t Adafruit_ADS1015::getLastConversionResults()
jortronm2 0:4096be81b17f 309 {
jortronm2 0:4096be81b17f 310 // Wait for the conversion to complete
jortronm2 0:4096be81b17f 311 wait_ms(m_conversionDelay);
jortronm2 0:4096be81b17f 312
jortronm2 0:4096be81b17f 313 // Read the conversion results
jortronm2 0:4096be81b17f 314 uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift;
jortronm2 0:4096be81b17f 315 if (m_bitShift == 0) {
jortronm2 0:4096be81b17f 316 return (int16_t)res;
jortronm2 0:4096be81b17f 317 } else {
jortronm2 0:4096be81b17f 318 // Shift 12-bit results right 4 bits for the ADS1015,
jortronm2 0:4096be81b17f 319 // making sure we keep the sign bit intact
jortronm2 0:4096be81b17f 320 if (res > 0x07FF) {
jortronm2 0:4096be81b17f 321 // negative number - extend the sign to 16th bit
jortronm2 0:4096be81b17f 322 res |= 0xF000;
jortronm2 0:4096be81b17f 323 }
jortronm2 0:4096be81b17f 324 return (int16_t)res;
jortronm2 0:4096be81b17f 325 }
jortronm2 0:4096be81b17f 326 }