transfer
Adafruit_ADS1015.cpp@7:72e307987683, 2018-07-24 (annotated)
- Committer:
- cgoyette
- Date:
- Tue Jul 24 16:53:15 2018 +0000
- Revision:
- 7:72e307987683
- Parent:
- 6:4c38bb36099c
removed debug messages.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
arve0 | 0:8174d9ceeca1 | 1 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 2 | /*! |
arve0 | 0:8174d9ceeca1 | 3 | @file Adafruit_ADS1015.cpp |
arve0 | 0:8174d9ceeca1 | 4 | @author K.Townsend (Adafruit Industries) |
arve0 | 0:8174d9ceeca1 | 5 | @license BSD (see LICENSE.txt) |
arve0 | 0:8174d9ceeca1 | 6 | |
arve0 | 0:8174d9ceeca1 | 7 | Ported to mbed by Arve Seljebu - arve0.github.io |
arve0 | 0:8174d9ceeca1 | 8 | |
arve0 | 0:8174d9ceeca1 | 9 | Driver for the ADS1015/ADS1115 ADC |
arve0 | 0:8174d9ceeca1 | 10 | |
arve0 | 0:8174d9ceeca1 | 11 | This is a library for the Adafruit MPL115A2 breakout |
arve0 | 0:8174d9ceeca1 | 12 | ----> https://www.adafruit.com/products/1083 |
arve0 | 0:8174d9ceeca1 | 13 | |
arve0 | 0:8174d9ceeca1 | 14 | Adafruit invests time and resources providing this open source code, |
arve0 | 0:8174d9ceeca1 | 15 | please support Adafruit and open-source hardware by purchasing |
arve0 | 0:8174d9ceeca1 | 16 | products from Adafruit! |
arve0 | 0:8174d9ceeca1 | 17 | |
arve0 | 0:8174d9ceeca1 | 18 | @section HISTORY |
arve0 | 0:8174d9ceeca1 | 19 | |
arve0 | 0:8174d9ceeca1 | 20 | v1.0 - First release |
arve0 | 0:8174d9ceeca1 | 21 | v1.1.1 - Ported to mbed |
arve0 | 0:8174d9ceeca1 | 22 | */ |
arve0 | 0:8174d9ceeca1 | 23 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 24 | |
arve0 | 0:8174d9ceeca1 | 25 | #include <mbed.h> |
arve0 | 0:8174d9ceeca1 | 26 | #include "Adafruit_ADS1015.h" |
arve0 | 0:8174d9ceeca1 | 27 | |
arve0 | 0:8174d9ceeca1 | 28 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 29 | /*! |
arve0 | 0:8174d9ceeca1 | 30 | @brief Writes 16-bits to the specified destination register |
arve0 | 0:8174d9ceeca1 | 31 | */ |
arve0 | 0:8174d9ceeca1 | 32 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 33 | void Adafruit_ADS1015::writeRegister(uint8_t i2cAddress, uint8_t reg, uint16_t value) |
arve0 | 3:fb735fb343de | 34 | { |
cgoyette | 7:72e307987683 | 35 | //printf("ADC-wr1\r\n"); |
arve0 | 3:fb735fb343de | 36 | char cmd[3]; |
arve0 | 3:fb735fb343de | 37 | cmd[0] = (char)reg; |
cgoyette | 7:72e307987683 | 38 | //printf("ADC-wr cmd0=%i\r\n", cmd[0]); |
cgoyette | 7:72e307987683 | 39 | //printf("ADC-wr2\r\n"); |
arve0 | 3:fb735fb343de | 40 | cmd[1] = (char)(value>>8); |
cgoyette | 7:72e307987683 | 41 | //printf("ADC-wr cmd1=%i\r\n", cmd[1]); |
cgoyette | 7:72e307987683 | 42 | //printf("ADC-wr3\r\n"); |
arve0 | 3:fb735fb343de | 43 | cmd[2] = (char)(value & 0xFF); |
cgoyette | 7:72e307987683 | 44 | //printf("ADC-wr cmd2=%i\r\n", cmd[2]); |
cgoyette | 7:72e307987683 | 45 | //printf("ADC-wr4\r\n"); |
cgoyette | 7:72e307987683 | 46 | //printf("i2c-Write return = %i\r\n", m_i2c->write(i2cAddress, cmd, 3)); |
arve0 | 3:fb735fb343de | 47 | m_i2c->write(i2cAddress, cmd, 3); |
cgoyette | 7:72e307987683 | 48 | //printf("ADC-wr5\r\n"); |
arve0 | 0:8174d9ceeca1 | 49 | } |
arve0 | 0:8174d9ceeca1 | 50 | |
arve0 | 0:8174d9ceeca1 | 51 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 52 | /*! |
arve0 | 0:8174d9ceeca1 | 53 | @brief Reads 16-bits from the specified register |
arve0 | 0:8174d9ceeca1 | 54 | */ |
arve0 | 0:8174d9ceeca1 | 55 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 56 | uint16_t Adafruit_ADS1015::readRegister(uint8_t i2cAddress, uint8_t reg) |
arve0 | 3:fb735fb343de | 57 | { |
cgoyette | 7:72e307987683 | 58 | //printf("ADC-RR1\r\n"); |
arve0 | 3:fb735fb343de | 59 | char data[2]; |
cgoyette | 7:72e307987683 | 60 | //printf("ADC-RR2\r\n"); |
arve0 | 3:fb735fb343de | 61 | data[0] = reg; // temporary use this to send address to conversion register |
cgoyette | 7:72e307987683 | 62 | //printf("ADC-RR3\r\n"); |
arve0 | 3:fb735fb343de | 63 | m_i2c->write(i2cAddress, data, 1); |
cgoyette | 7:72e307987683 | 64 | //printf("ADC-RR4\r\n"); |
arve0 | 3:fb735fb343de | 65 | m_i2c->read(i2cAddress, data, 2); |
cgoyette | 7:72e307987683 | 66 | //printf("ADC-RR5\r\n"); |
arve0 | 3:fb735fb343de | 67 | return (data[0] << 8 | data [1]); |
arve0 | 0:8174d9ceeca1 | 68 | } |
arve0 | 0:8174d9ceeca1 | 69 | |
arve0 | 0:8174d9ceeca1 | 70 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 71 | /*! |
arve0 | 0:8174d9ceeca1 | 72 | @brief Instantiates a new ADS1015 class w/appropriate properties |
arve0 | 0:8174d9ceeca1 | 73 | */ |
arve0 | 0:8174d9ceeca1 | 74 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 75 | Adafruit_ADS1015::Adafruit_ADS1015(I2C* i2c, uint8_t i2cAddress) |
arve0 | 0:8174d9ceeca1 | 76 | { |
arve0 | 3:fb735fb343de | 77 | // shift 7 bit address 1 left: read expects 8 bit address, see I2C.h |
arve0 | 3:fb735fb343de | 78 | m_i2cAddress = i2cAddress << 1; |
arve0 | 3:fb735fb343de | 79 | m_conversionDelay = ADS1015_CONVERSIONDELAY; |
arve0 | 3:fb735fb343de | 80 | m_bitShift = 4; |
arve0 | 3:fb735fb343de | 81 | m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */ |
arve0 | 3:fb735fb343de | 82 | m_i2c = i2c; |
arve0 | 0:8174d9ceeca1 | 83 | } |
arve0 | 0:8174d9ceeca1 | 84 | |
arve0 | 0:8174d9ceeca1 | 85 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 86 | /*! |
arve0 | 0:8174d9ceeca1 | 87 | @brief Instantiates a new ADS1115 class w/appropriate properties |
arve0 | 0:8174d9ceeca1 | 88 | */ |
arve0 | 0:8174d9ceeca1 | 89 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 90 | Adafruit_ADS1115::Adafruit_ADS1115(I2C* i2c, uint8_t i2cAddress) |
arve0 | 0:8174d9ceeca1 | 91 | { |
arve0 | 3:fb735fb343de | 92 | // shift 7 bit address 1 left: read expects 8 bit address, see mbed's I2C.h |
arve0 | 3:fb735fb343de | 93 | m_i2cAddress = i2cAddress << 1; |
cgoyette | 7:72e307987683 | 94 | //printf("12c-address=%i\r\n", m_i2cAddress); |
arve0 | 3:fb735fb343de | 95 | m_conversionDelay = ADS1115_CONVERSIONDELAY; |
arve0 | 3:fb735fb343de | 96 | m_bitShift = 0; |
arve0 | 3:fb735fb343de | 97 | m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */ |
arve0 | 3:fb735fb343de | 98 | m_i2c = i2c; |
arve0 | 0:8174d9ceeca1 | 99 | } |
arve0 | 0:8174d9ceeca1 | 100 | |
arve0 | 0:8174d9ceeca1 | 101 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 102 | /*! |
arve0 | 0:8174d9ceeca1 | 103 | @brief Sets the gain and input voltage range |
arve0 | 0:8174d9ceeca1 | 104 | */ |
arve0 | 0:8174d9ceeca1 | 105 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 106 | void Adafruit_ADS1015::setGain(adsGain_t gain) |
arve0 | 0:8174d9ceeca1 | 107 | { |
arve0 | 3:fb735fb343de | 108 | m_gain = gain; |
arve0 | 0:8174d9ceeca1 | 109 | } |
arve0 | 0:8174d9ceeca1 | 110 | |
arve0 | 0:8174d9ceeca1 | 111 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 112 | /*! |
arve0 | 0:8174d9ceeca1 | 113 | @brief Gets a gain and input voltage range |
arve0 | 0:8174d9ceeca1 | 114 | */ |
arve0 | 0:8174d9ceeca1 | 115 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 116 | adsGain_t Adafruit_ADS1015::getGain() |
arve0 | 0:8174d9ceeca1 | 117 | { |
arve0 | 3:fb735fb343de | 118 | return m_gain; |
arve0 | 0:8174d9ceeca1 | 119 | } |
arve0 | 0:8174d9ceeca1 | 120 | |
arve0 | 0:8174d9ceeca1 | 121 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 122 | /*! |
arve0 | 0:8174d9ceeca1 | 123 | @brief Gets a single-ended ADC reading from the specified channel |
arve0 | 0:8174d9ceeca1 | 124 | */ |
arve0 | 0:8174d9ceeca1 | 125 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 126 | uint16_t Adafruit_ADS1015::readADC_SingleEnded(uint8_t channel) |
arve0 | 3:fb735fb343de | 127 | { |
cgoyette | 7:72e307987683 | 128 | //printf("ADC1\r\n"); |
cgoyette | 7:72e307987683 | 129 | //printf("channel = %i\r\n", channel); |
arve0 | 3:fb735fb343de | 130 | if (channel > 3) { |
cgoyette | 7:72e307987683 | 131 | //printf("ADC2\r\n"); |
arve0 | 3:fb735fb343de | 132 | return 0; |
arve0 | 3:fb735fb343de | 133 | } |
cgoyette | 7:72e307987683 | 134 | //printf("ADC3\r\n"); |
arve0 | 3:fb735fb343de | 135 | // Start with default values |
arve0 | 3:fb735fb343de | 136 | uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) |
arve0 | 3:fb735fb343de | 137 | ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) |
arve0 | 3:fb735fb343de | 138 | ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) |
arve0 | 3:fb735fb343de | 139 | ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) |
arve0 | 4:6445a678d458 | 140 | ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default) |
arve0 | 3:fb735fb343de | 141 | ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) |
arve0 | 3:fb735fb343de | 142 | |
arve0 | 3:fb735fb343de | 143 | // Set PGA/voltage range |
cgoyette | 7:72e307987683 | 144 | //printf("ADC4\r\n"); |
arve0 | 3:fb735fb343de | 145 | config |= m_gain; |
cgoyette | 7:72e307987683 | 146 | //printf("ADC5\r\n"); |
arve0 | 3:fb735fb343de | 147 | // Set single-ended input channel |
arve0 | 3:fb735fb343de | 148 | switch (channel) { |
arve0 | 3:fb735fb343de | 149 | case (0): |
cgoyette | 7:72e307987683 | 150 | //printf("ADC6\r\n"); |
arve0 | 3:fb735fb343de | 151 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_0; |
cgoyette | 7:72e307987683 | 152 | //printf("ADC7\r\n"); |
arve0 | 3:fb735fb343de | 153 | break; |
arve0 | 3:fb735fb343de | 154 | case (1): |
cgoyette | 7:72e307987683 | 155 | //printf("ADC8\r\n"); |
arve0 | 3:fb735fb343de | 156 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_1; |
cgoyette | 7:72e307987683 | 157 | //printf("ADC9\r\n"); |
arve0 | 3:fb735fb343de | 158 | break; |
arve0 | 3:fb735fb343de | 159 | case (2): |
cgoyette | 7:72e307987683 | 160 | //printf("ADC10\r\n"); |
arve0 | 3:fb735fb343de | 161 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_2; |
cgoyette | 7:72e307987683 | 162 | //printf("ADC11\r\n"); |
arve0 | 3:fb735fb343de | 163 | break; |
arve0 | 3:fb735fb343de | 164 | case (3): |
cgoyette | 7:72e307987683 | 165 | //printf("ADC12\r\n"); |
arve0 | 3:fb735fb343de | 166 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_3; |
cgoyette | 7:72e307987683 | 167 | //printf("ADC13\r\n"); |
arve0 | 3:fb735fb343de | 168 | break; |
arve0 | 3:fb735fb343de | 169 | } |
arve0 | 0:8174d9ceeca1 | 170 | |
arve0 | 3:fb735fb343de | 171 | // Set 'start single-conversion' bit |
cgoyette | 7:72e307987683 | 172 | //printf("ADC14\r\n"); |
arve0 | 3:fb735fb343de | 173 | config |= ADS1015_REG_CONFIG_OS_SINGLE; |
arve0 | 0:8174d9ceeca1 | 174 | |
arve0 | 3:fb735fb343de | 175 | // Write config register to the ADC |
cgoyette | 7:72e307987683 | 176 | //printf("ADC15\r\n"); |
arve0 | 3:fb735fb343de | 177 | writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); |
arve0 | 0:8174d9ceeca1 | 178 | |
arve0 | 3:fb735fb343de | 179 | // Wait for the conversion to complete |
cgoyette | 7:72e307987683 | 180 | //printf("ADC16\r\n"); |
arve0 | 3:fb735fb343de | 181 | wait_ms(m_conversionDelay); |
arve0 | 0:8174d9ceeca1 | 182 | |
arve0 | 3:fb735fb343de | 183 | // Read the conversion results |
arve0 | 3:fb735fb343de | 184 | // Shift 12-bit results right 4 bits for the ADS1015 |
cgoyette | 7:72e307987683 | 185 | //printf("ADC17\r\n"); |
arve0 | 3:fb735fb343de | 186 | return readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; |
arve0 | 0:8174d9ceeca1 | 187 | } |
arve0 | 0:8174d9ceeca1 | 188 | |
arve0 | 0:8174d9ceeca1 | 189 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 190 | /*! |
arve0 | 0:8174d9ceeca1 | 191 | @brief Reads the conversion results, measuring the voltage |
arve0 | 0:8174d9ceeca1 | 192 | difference between the P (AIN0) and N (AIN1) input. Generates |
arve0 | 0:8174d9ceeca1 | 193 | a signed value since the difference can be either |
arve0 | 0:8174d9ceeca1 | 194 | positive or negative. |
arve0 | 0:8174d9ceeca1 | 195 | */ |
arve0 | 0:8174d9ceeca1 | 196 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 197 | int16_t Adafruit_ADS1015::readADC_Differential_0_1() |
arve0 | 3:fb735fb343de | 198 | { |
arve0 | 3:fb735fb343de | 199 | // Start with default values |
arve0 | 3:fb735fb343de | 200 | uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) |
arve0 | 3:fb735fb343de | 201 | ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) |
arve0 | 3:fb735fb343de | 202 | ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) |
arve0 | 3:fb735fb343de | 203 | ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) |
arve0 | 4:6445a678d458 | 204 | ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default) |
arve0 | 3:fb735fb343de | 205 | ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) |
arve0 | 0:8174d9ceeca1 | 206 | |
arve0 | 3:fb735fb343de | 207 | // Set PGA/voltage range |
arve0 | 3:fb735fb343de | 208 | config |= m_gain; |
arve0 | 0:8174d9ceeca1 | 209 | |
arve0 | 3:fb735fb343de | 210 | // Set channels |
arve0 | 3:fb735fb343de | 211 | config |= ADS1015_REG_CONFIG_MUX_DIFF_0_1; // AIN0 = P, AIN1 = N |
arve0 | 0:8174d9ceeca1 | 212 | |
arve0 | 3:fb735fb343de | 213 | // Set 'start single-conversion' bit |
arve0 | 3:fb735fb343de | 214 | config |= ADS1015_REG_CONFIG_OS_SINGLE; |
arve0 | 0:8174d9ceeca1 | 215 | |
arve0 | 3:fb735fb343de | 216 | // Write config register to the ADC |
arve0 | 3:fb735fb343de | 217 | writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); |
arve0 | 3:fb735fb343de | 218 | |
arve0 | 3:fb735fb343de | 219 | // Wait for the conversion to complete |
arve0 | 3:fb735fb343de | 220 | wait_ms(m_conversionDelay); |
arve0 | 0:8174d9ceeca1 | 221 | |
arve0 | 3:fb735fb343de | 222 | // Read the conversion results |
arve0 | 3:fb735fb343de | 223 | uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; |
arve0 | 3:fb735fb343de | 224 | if (m_bitShift == 0) { |
arve0 | 3:fb735fb343de | 225 | return (int16_t)res; |
arve0 | 3:fb735fb343de | 226 | } else { |
arve0 | 3:fb735fb343de | 227 | // Shift 12-bit results right 4 bits for the ADS1015, |
arve0 | 3:fb735fb343de | 228 | // making sure we keep the sign bit intact |
arve0 | 3:fb735fb343de | 229 | if (res > 0x07FF) { |
arve0 | 3:fb735fb343de | 230 | // negative number - extend the sign to 16th bit |
arve0 | 3:fb735fb343de | 231 | res |= 0xF000; |
arve0 | 3:fb735fb343de | 232 | } |
arve0 | 3:fb735fb343de | 233 | return (int16_t)res; |
arve0 | 0:8174d9ceeca1 | 234 | } |
arve0 | 0:8174d9ceeca1 | 235 | } |
arve0 | 0:8174d9ceeca1 | 236 | |
arve0 | 0:8174d9ceeca1 | 237 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 238 | /*! |
arve0 | 0:8174d9ceeca1 | 239 | @brief Reads the conversion results, measuring the voltage |
arve0 | 0:8174d9ceeca1 | 240 | difference between the P (AIN2) and N (AIN3) input. Generates |
arve0 | 0:8174d9ceeca1 | 241 | a signed value since the difference can be either |
arve0 | 0:8174d9ceeca1 | 242 | positive or negative. |
arve0 | 0:8174d9ceeca1 | 243 | */ |
arve0 | 0:8174d9ceeca1 | 244 | /**************************************************************************/ |
arve0 | 3:fb735fb343de | 245 | int16_t Adafruit_ADS1015::readADC_Differential_2_3() |
arve0 | 3:fb735fb343de | 246 | { |
arve0 | 3:fb735fb343de | 247 | // Start with default values |
arve0 | 3:fb735fb343de | 248 | uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) |
arve0 | 3:fb735fb343de | 249 | ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) |
arve0 | 3:fb735fb343de | 250 | ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) |
arve0 | 3:fb735fb343de | 251 | ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) |
arve0 | 4:6445a678d458 | 252 | ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default) |
arve0 | 3:fb735fb343de | 253 | ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) |
arve0 | 0:8174d9ceeca1 | 254 | |
arve0 | 3:fb735fb343de | 255 | // Set PGA/voltage range |
arve0 | 3:fb735fb343de | 256 | config |= m_gain; |
arve0 | 0:8174d9ceeca1 | 257 | |
arve0 | 3:fb735fb343de | 258 | // Set channels |
arve0 | 3:fb735fb343de | 259 | config |= ADS1015_REG_CONFIG_MUX_DIFF_2_3; // AIN2 = P, AIN3 = N |
arve0 | 0:8174d9ceeca1 | 260 | |
arve0 | 3:fb735fb343de | 261 | // Set 'start single-conversion' bit |
arve0 | 3:fb735fb343de | 262 | config |= ADS1015_REG_CONFIG_OS_SINGLE; |
arve0 | 0:8174d9ceeca1 | 263 | |
arve0 | 3:fb735fb343de | 264 | // Write config register to the ADC |
arve0 | 3:fb735fb343de | 265 | writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); |
arve0 | 3:fb735fb343de | 266 | |
arve0 | 3:fb735fb343de | 267 | // Wait for the conversion to complete |
arve0 | 3:fb735fb343de | 268 | wait_ms(m_conversionDelay); |
arve0 | 0:8174d9ceeca1 | 269 | |
arve0 | 3:fb735fb343de | 270 | // Read the conversion results |
arve0 | 3:fb735fb343de | 271 | uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; |
arve0 | 3:fb735fb343de | 272 | if (m_bitShift == 0) { |
arve0 | 3:fb735fb343de | 273 | return (int16_t)res; |
arve0 | 3:fb735fb343de | 274 | } else { |
arve0 | 3:fb735fb343de | 275 | // Shift 12-bit results right 4 bits for the ADS1015, |
arve0 | 3:fb735fb343de | 276 | // making sure we keep the sign bit intact |
arve0 | 3:fb735fb343de | 277 | if (res > 0x07FF) { |
arve0 | 3:fb735fb343de | 278 | // negative number - extend the sign to 16th bit |
arve0 | 3:fb735fb343de | 279 | res |= 0xF000; |
arve0 | 3:fb735fb343de | 280 | } |
arve0 | 3:fb735fb343de | 281 | return (int16_t)res; |
arve0 | 0:8174d9ceeca1 | 282 | } |
arve0 | 0:8174d9ceeca1 | 283 | } |
arve0 | 0:8174d9ceeca1 | 284 | |
arve0 | 0:8174d9ceeca1 | 285 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 286 | /*! |
arve0 | 0:8174d9ceeca1 | 287 | @brief Sets up the comparator to operate in basic mode, causing the |
arve0 | 0:8174d9ceeca1 | 288 | ALERT/RDY pin to assert (go from high to low) when the ADC |
arve0 | 0:8174d9ceeca1 | 289 | value exceeds the specified threshold. |
arve0 | 0:8174d9ceeca1 | 290 | |
arve0 | 0:8174d9ceeca1 | 291 | This will also set the ADC in continuous conversion mode. |
arve0 | 0:8174d9ceeca1 | 292 | */ |
arve0 | 0:8174d9ceeca1 | 293 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 294 | void Adafruit_ADS1015::startComparator_SingleEnded(uint8_t channel, int16_t threshold) |
arve0 | 0:8174d9ceeca1 | 295 | { |
arve0 | 3:fb735fb343de | 296 | // Start with default values |
arve0 | 3:fb735fb343de | 297 | uint16_t config = ADS1015_REG_CONFIG_CQUE_1CONV | // Comparator enabled and asserts on 1 match |
arve0 | 3:fb735fb343de | 298 | ADS1015_REG_CONFIG_CLAT_LATCH | // Latching mode |
arve0 | 3:fb735fb343de | 299 | ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) |
arve0 | 3:fb735fb343de | 300 | ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) |
arve0 | 4:6445a678d458 | 301 | ADS1015_REG_CONFIG_DR_1600SPS | // 1600(ADS1015) or 250(ADS1115) samples per second (default) |
arve0 | 3:fb735fb343de | 302 | ADS1015_REG_CONFIG_MODE_CONTIN | // Continuous conversion mode |
arve0 | 3:fb735fb343de | 303 | ADS1015_REG_CONFIG_MODE_CONTIN; // Continuous conversion mode |
arve0 | 3:fb735fb343de | 304 | |
arve0 | 3:fb735fb343de | 305 | // Set PGA/voltage range |
arve0 | 3:fb735fb343de | 306 | config |= m_gain; |
arve0 | 0:8174d9ceeca1 | 307 | |
arve0 | 3:fb735fb343de | 308 | // Set single-ended input channel |
arve0 | 3:fb735fb343de | 309 | switch (channel) { |
arve0 | 3:fb735fb343de | 310 | case (0): |
arve0 | 3:fb735fb343de | 311 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_0; |
arve0 | 3:fb735fb343de | 312 | break; |
arve0 | 3:fb735fb343de | 313 | case (1): |
arve0 | 3:fb735fb343de | 314 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_1; |
arve0 | 3:fb735fb343de | 315 | break; |
arve0 | 3:fb735fb343de | 316 | case (2): |
arve0 | 3:fb735fb343de | 317 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_2; |
arve0 | 3:fb735fb343de | 318 | break; |
arve0 | 3:fb735fb343de | 319 | case (3): |
arve0 | 3:fb735fb343de | 320 | config |= ADS1015_REG_CONFIG_MUX_SINGLE_3; |
arve0 | 3:fb735fb343de | 321 | break; |
arve0 | 3:fb735fb343de | 322 | } |
arve0 | 0:8174d9ceeca1 | 323 | |
arve0 | 3:fb735fb343de | 324 | // Set the high threshold register |
arve0 | 3:fb735fb343de | 325 | // Shift 12-bit results left 4 bits for the ADS1015 |
arve0 | 3:fb735fb343de | 326 | writeRegister(m_i2cAddress, ADS1015_REG_POINTER_HITHRESH, threshold << m_bitShift); |
arve0 | 0:8174d9ceeca1 | 327 | |
arve0 | 3:fb735fb343de | 328 | // Write config register to the ADC |
arve0 | 3:fb735fb343de | 329 | writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); |
arve0 | 0:8174d9ceeca1 | 330 | } |
arve0 | 0:8174d9ceeca1 | 331 | |
arve0 | 0:8174d9ceeca1 | 332 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 333 | /*! |
arve0 | 0:8174d9ceeca1 | 334 | @brief In order to clear the comparator, we need to read the |
arve0 | 0:8174d9ceeca1 | 335 | conversion results. This function reads the last conversion |
arve0 | 0:8174d9ceeca1 | 336 | results without changing the config value. |
arve0 | 0:8174d9ceeca1 | 337 | */ |
arve0 | 0:8174d9ceeca1 | 338 | /**************************************************************************/ |
arve0 | 0:8174d9ceeca1 | 339 | int16_t Adafruit_ADS1015::getLastConversionResults() |
arve0 | 0:8174d9ceeca1 | 340 | { |
arve0 | 3:fb735fb343de | 341 | // Wait for the conversion to complete |
arve0 | 3:fb735fb343de | 342 | wait_ms(m_conversionDelay); |
arve0 | 0:8174d9ceeca1 | 343 | |
arve0 | 3:fb735fb343de | 344 | // Read the conversion results |
arve0 | 3:fb735fb343de | 345 | uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; |
arve0 | 3:fb735fb343de | 346 | if (m_bitShift == 0) { |
arve0 | 3:fb735fb343de | 347 | return (int16_t)res; |
arve0 | 3:fb735fb343de | 348 | } else { |
arve0 | 3:fb735fb343de | 349 | // Shift 12-bit results right 4 bits for the ADS1015, |
arve0 | 3:fb735fb343de | 350 | // making sure we keep the sign bit intact |
arve0 | 3:fb735fb343de | 351 | if (res > 0x07FF) { |
arve0 | 3:fb735fb343de | 352 | // negative number - extend the sign to 16th bit |
arve0 | 3:fb735fb343de | 353 | res |= 0xF000; |
arve0 | 3:fb735fb343de | 354 | } |
arve0 | 3:fb735fb343de | 355 | return (int16_t)res; |
arve0 | 0:8174d9ceeca1 | 356 | } |
arve0 | 3:fb735fb343de | 357 | } |