Rick McConney / Mbed 2 deprecated StarterKit

GSMA version

Dependencies:   FXOS8700CQ mbed

Fork of AvnetATT_shape_hackathon by Rick McConney

hts221_driver.cpp@45:fe90f1fcb4e0, 2016-11-30 (annotated)

Committer:
elmkom
Date:
Wed Nov 30 14:50:16 2016 +0000
Revision:
45:fe90f1fcb4e0
Parent:
30:48b43538e98b 
gsma version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
JMF 0:9d5134074d84 1
JMF 0:9d5134074d84 2 #include "HTS221.h"
JMF 0:9d5134074d84 3
JMF 0:9d5134074d84 4
JMF 0:9d5134074d84 5 // ------------------------------------------------------------------------------
JMF 0:9d5134074d84 6 //jmf -- define I2C pins and functions to read & write to I2C device
JMF 0:9d5134074d84 7
JMF 0:9d5134074d84 8 #include <string>
JMF 0:9d5134074d84 9 #include "mbed.h"
JMF 0:9d5134074d84 10
stefanrousseau 11:e6602513730f 11 #include "hardware.h"
JMF 28:886833917643 12 //I2C i2c(PTC11, PTC10); //SDA, SCL -- define the I2C pins being used. Defined in a
JMF 28:886833917643 13 //common locatioin since sensors also use I2C
JMF 0:9d5134074d84 14
JMF 0:9d5134074d84 15 // Read a single unsigned char from addressToRead and return it as a unsigned char
JMF 0:9d5134074d84 16 unsigned char HTS221::readRegister(unsigned char slaveAddress, unsigned char ToRead)
JMF 0:9d5134074d84 17 {
JMF 0:9d5134074d84 18 char data = ToRead;
JMF 0:9d5134074d84 19
stefanrousseau 30:48b43538e98b 20 i2c.write(slaveAddress, &data, 1, 1);
JMF 0:9d5134074d84 21 i2c.read(slaveAddress, &data, 1, 0);
JMF 0:9d5134074d84 22 return data;
JMF 0:9d5134074d84 23 }
JMF 0:9d5134074d84 24
JMF 0:9d5134074d84 25 // Writes a single unsigned char (dataToWrite) into regToWrite
JMF 0:9d5134074d84 26 int HTS221::writeRegister(unsigned char slaveAddress, unsigned char regToWrite, unsigned char dataToWrite)
JMF 0:9d5134074d84 27 {
JMF 0:9d5134074d84 28 const char data[] = {regToWrite, dataToWrite};
JMF 0:9d5134074d84 29
JMF 0:9d5134074d84 30 return i2c.write(slaveAddress,data,2,0);
JMF 0:9d5134074d84 31 }
JMF 0:9d5134074d84 32
JMF 0:9d5134074d84 33
JMF 0:9d5134074d84 34 //jmf end
JMF 0:9d5134074d84 35 // ------------------------------------------------------------------------------
JMF 0:9d5134074d84 36
JMF 1:af7a42f7d465 37 //static inline int humidityReady(uint8_t data) {
JMF 1:af7a42f7d465 38 // return (data & 0x02);
JMF 1:af7a42f7d465 39 //}
JMF 1:af7a42f7d465 40 //static inline int temperatureReady(uint8_t data) {
JMF 1:af7a42f7d465 41 // return (data & 0x01);
JMF 1:af7a42f7d465 42 //}
JMF 0:9d5134074d84 43
JMF 0:9d5134074d84 44
JMF 0:9d5134074d84 45 HTS221::HTS221(void) : _address(HTS221_ADDRESS)
JMF 0:9d5134074d84 46 {
JMF 0:9d5134074d84 47 _temperature = 0;
JMF 0:9d5134074d84 48 _humidity = 0;
JMF 0:9d5134074d84 49 }
JMF 0:9d5134074d84 50
JMF 0:9d5134074d84 51
JMF 0:9d5134074d84 52 int HTS221::begin(void)
JMF 0:9d5134074d84 53 {
JMF 0:9d5134074d84 54 uint8_t data;
JMF 0:9d5134074d84 55
JMF 0:9d5134074d84 56 data = readRegister(_address, WHO_AM_I);
JMF 0:9d5134074d84 57 if (data == WHO_AM_I_RETURN){
JMF 0:9d5134074d84 58 if (activate()){
JMF 0:9d5134074d84 59 storeCalibration();
JMF 0:9d5134074d84 60 return data;
JMF 0:9d5134074d84 61 }
JMF 0:9d5134074d84 62 }
JMF 0:9d5134074d84 63
JMF 0:9d5134074d84 64 return 0;
JMF 0:9d5134074d84 65 }
JMF 0:9d5134074d84 66
JMF 0:9d5134074d84 67 int
JMF 0:9d5134074d84 68 HTS221::storeCalibration(void)
JMF 0:9d5134074d84 69 {
JMF 0:9d5134074d84 70 uint8_t data;
JMF 0:9d5134074d84 71 uint16_t tmp;
JMF 0:9d5134074d84 72
JMF 0:9d5134074d84 73 for (int reg=CALIB_START; reg<=CALIB_END; reg++) {
JMF 0:9d5134074d84 74 if ((reg!=CALIB_START+8) && (reg!=CALIB_START+9) && (reg!=CALIB_START+4)) {
JMF 0:9d5134074d84 75
JMF 0:9d5134074d84 76 data = readRegister(HTS221_ADDRESS, reg);
JMF 0:9d5134074d84 77
JMF 0:9d5134074d84 78 switch (reg) {
JMF 0:9d5134074d84 79 case CALIB_START:
JMF 0:9d5134074d84 80 _h0_rH = data;
JMF 0:9d5134074d84 81 break;
JMF 0:9d5134074d84 82 case CALIB_START+1:
JMF 0:9d5134074d84 83 _h1_rH = data;
JMF 0:9d5134074d84 84 break;
JMF 0:9d5134074d84 85 case CALIB_START+2:
JMF 0:9d5134074d84 86 _T0_degC = data;
JMF 0:9d5134074d84 87 break;
JMF 0:9d5134074d84 88 case CALIB_START+3:
JMF 0:9d5134074d84 89 _T1_degC = data;
JMF 0:9d5134074d84 90 break;
JMF 0:9d5134074d84 91
JMF 0:9d5134074d84 92 case CALIB_START+5:
JMF 0:9d5134074d84 93 tmp = _T0_degC;
JMF 0:9d5134074d84 94 _T0_degC = (data&0x3)<<8;
JMF 0:9d5134074d84 95 _T0_degC |= tmp;
JMF 0:9d5134074d84 96
JMF 0:9d5134074d84 97 tmp = _T1_degC;
JMF 0:9d5134074d84 98 _T1_degC = ((data&0xC)>>2)<<8;
JMF 0:9d5134074d84 99 _T1_degC |= tmp;
JMF 0:9d5134074d84 100 break;
JMF 0:9d5134074d84 101 case CALIB_START+6:
JMF 0:9d5134074d84 102 _H0_T0 = data;
JMF 0:9d5134074d84 103 break;
JMF 0:9d5134074d84 104 case CALIB_START+7:
JMF 0:9d5134074d84 105 _H0_T0 |= data<<8;
JMF 0:9d5134074d84 106 break;
JMF 0:9d5134074d84 107 case CALIB_START+0xA:
JMF 0:9d5134074d84 108 _H1_T0 = data;
JMF 0:9d5134074d84 109 break;
JMF 0:9d5134074d84 110 case CALIB_START+0xB:
JMF 0:9d5134074d84 111 _H1_T0 |= data <<8;
JMF 0:9d5134074d84 112 break;
JMF 0:9d5134074d84 113 case CALIB_START+0xC:
JMF 0:9d5134074d84 114 _T0_OUT = data;
JMF 0:9d5134074d84 115 break;
JMF 0:9d5134074d84 116 case CALIB_START+0xD:
JMF 0:9d5134074d84 117 _T0_OUT |= data << 8;
JMF 0:9d5134074d84 118 break;
JMF 0:9d5134074d84 119 case CALIB_START+0xE:
JMF 0:9d5134074d84 120 _T1_OUT = data;
JMF 0:9d5134074d84 121 break;
JMF 0:9d5134074d84 122 case CALIB_START+0xF:
JMF 0:9d5134074d84 123 _T1_OUT |= data << 8;
JMF 0:9d5134074d84 124 break;
JMF 0:9d5134074d84 125
JMF 0:9d5134074d84 126
JMF 0:9d5134074d84 127 case CALIB_START+8:
JMF 0:9d5134074d84 128 case CALIB_START+9:
JMF 0:9d5134074d84 129 case CALIB_START+4:
JMF 0:9d5134074d84 130 //DO NOTHING
JMF 0:9d5134074d84 131 break;
JMF 0:9d5134074d84 132
JMF 0:9d5134074d84 133 // to cover any possible error
JMF 0:9d5134074d84 134 default:
JMF 0:9d5134074d84 135 return false;
JMF 0:9d5134074d84 136 } /* switch */
JMF 0:9d5134074d84 137 } /* if */
JMF 0:9d5134074d84 138 } /* for */
JMF 0:9d5134074d84 139 return true;
JMF 0:9d5134074d84 140 }
JMF 0:9d5134074d84 141
JMF 0:9d5134074d84 142
JMF 0:9d5134074d84 143 int
JMF 0:9d5134074d84 144 HTS221::activate(void)
JMF 0:9d5134074d84 145 {
JMF 0:9d5134074d84 146 uint8_t data;
JMF 0:9d5134074d84 147
JMF 0:9d5134074d84 148 data = readRegister(_address, CTRL_REG1);
JMF 0:9d5134074d84 149 data |= POWER_UP;
JMF 0:9d5134074d84 150 data |= ODR0_SET;
JMF 0:9d5134074d84 151 writeRegister(_address, CTRL_REG1, data);
JMF 0:9d5134074d84 152
JMF 0:9d5134074d84 153 return true;
JMF 0:9d5134074d84 154 }
JMF 0:9d5134074d84 155
JMF 0:9d5134074d84 156
JMF 0:9d5134074d84 157 int HTS221::deactivate(void)
JMF 0:9d5134074d84 158 {
JMF 0:9d5134074d84 159 uint8_t data;
JMF 0:9d5134074d84 160
JMF 0:9d5134074d84 161 data = readRegister(_address, CTRL_REG1);
JMF 0:9d5134074d84 162 data &= ~POWER_UP;
JMF 0:9d5134074d84 163 writeRegister(_address, CTRL_REG1, data);
JMF 0:9d5134074d84 164 return true;
JMF 0:9d5134074d84 165 }
JMF 0:9d5134074d84 166
JMF 0:9d5134074d84 167
JMF 0:9d5134074d84 168 int
JMF 0:9d5134074d84 169 HTS221::bduActivate(void)
JMF 0:9d5134074d84 170 {
JMF 0:9d5134074d84 171 uint8_t data;
JMF 0:9d5134074d84 172
JMF 0:9d5134074d84 173 data = readRegister(_address, CTRL_REG1);
JMF 0:9d5134074d84 174 data |= BDU_SET;
JMF 0:9d5134074d84 175 writeRegister(_address, CTRL_REG1, data);
JMF 0:9d5134074d84 176
JMF 0:9d5134074d84 177 return true;
JMF 0:9d5134074d84 178 }
JMF 0:9d5134074d84 179
JMF 0:9d5134074d84 180
JMF 0:9d5134074d84 181 int
JMF 0:9d5134074d84 182 HTS221::bduDeactivate(void)
JMF 0:9d5134074d84 183 {
JMF 0:9d5134074d84 184 uint8_t data;
JMF 0:9d5134074d84 185
JMF 0:9d5134074d84 186 data = readRegister(_address, CTRL_REG1);
JMF 0:9d5134074d84 187 data &= ~BDU_SET;
JMF 0:9d5134074d84 188 writeRegister(_address, CTRL_REG1, data);
JMF 0:9d5134074d84 189 return true;
JMF 0:9d5134074d84 190 }
JMF 0:9d5134074d84 191
JMF 0:9d5134074d84 192
JMF 0:9d5134074d84 193 int
JMF 0:9d5134074d84 194 HTS221::readHumidity(void)
JMF 0:9d5134074d84 195 {
JMF 0:9d5134074d84 196 uint8_t data = 0;
JMF 0:9d5134074d84 197 uint16_t h_out = 0;
JMF 0:9d5134074d84 198 double h_temp = 0.0;
JMF 0:9d5134074d84 199 double hum = 0.0;
JMF 0:9d5134074d84 200
JMF 0:9d5134074d84 201 data = readRegister(_address, STATUS_REG);
JMF 0:9d5134074d84 202
JMF 0:9d5134074d84 203 if (data & HUMIDITY_READY) {
JMF 0:9d5134074d84 204 data = readRegister(_address, HUMIDITY_H_REG);
JMF 0:9d5134074d84 205 h_out = data << 8; // MSB
JMF 0:9d5134074d84 206 data = readRegister(_address, HUMIDITY_L_REG);
JMF 0:9d5134074d84 207 h_out |= data; // LSB
JMF 0:9d5134074d84 208
JMF 0:9d5134074d84 209 // Decode Humidity
JMF 0:9d5134074d84 210 hum = ((int16_t)(_h1_rH) - (int16_t)(_h0_rH))/2.0; // remove x2 multiple
JMF 0:9d5134074d84 211
JMF 0:9d5134074d84 212 // Calculate humidity in decimal of grade centigrades i.e. 15.0 = 150.
JMF 0:9d5134074d84 213 h_temp = (((int16_t)h_out - (int16_t)_H0_T0) * hum) / ((int16_t)_H1_T0 - (int16_t)_H0_T0);
JMF 0:9d5134074d84 214 hum = ((int16_t)_h0_rH) / 2.0; // remove x2 multiple
JMF 0:9d5134074d84 215 _humidity = (int16_t)((hum + h_temp)); // provide signed % measurement unit
JMF 0:9d5134074d84 216 }
JMF 0:9d5134074d84 217 return _humidity;
JMF 0:9d5134074d84 218 }
JMF 0:9d5134074d84 219
JMF 0:9d5134074d84 220
JMF 0:9d5134074d84 221
JMF 0:9d5134074d84 222 double
JMF 0:9d5134074d84 223 HTS221::readTemperature(void)
JMF 0:9d5134074d84 224 {
JMF 0:9d5134074d84 225 uint8_t data = 0;
JMF 0:9d5134074d84 226 uint16_t t_out = 0;
JMF 0:9d5134074d84 227 double t_temp = 0.0;
JMF 0:9d5134074d84 228 double deg = 0.0;
JMF 0:9d5134074d84 229
JMF 0:9d5134074d84 230 data = readRegister(_address, STATUS_REG);
JMF 0:9d5134074d84 231
JMF 0:9d5134074d84 232 if (data & TEMPERATURE_READY) {
JMF 0:9d5134074d84 233
JMF 0:9d5134074d84 234 data= readRegister(_address, TEMP_H_REG);
JMF 0:9d5134074d84 235 t_out = data << 8; // MSB
JMF 0:9d5134074d84 236 data = readRegister(_address, TEMP_L_REG);
JMF 0:9d5134074d84 237 t_out |= data; // LSB
JMF 0:9d5134074d84 238
JMF 0:9d5134074d84 239 // Decode Temperature
JMF 0:9d5134074d84 240 deg = ((int16_t)(_T1_degC) - (int16_t)(_T0_degC))/8.0; // remove x8 multiple
JMF 0:9d5134074d84 241
JMF 0:9d5134074d84 242 // Calculate Temperature in decimal of grade centigrades i.e. 15.0 = 150.
JMF 0:9d5134074d84 243 t_temp = (((int16_t)t_out - (int16_t)_T0_OUT) * deg) / ((int16_t)_T1_OUT - (int16_t)_T0_OUT);
JMF 0:9d5134074d84 244 deg = ((int16_t)_T0_degC) / 8.0; // remove x8 multiple
JMF 0:9d5134074d84 245 _temperature = deg + t_temp; // provide signed celsius measurement unit
JMF 0:9d5134074d84 246 }
JMF 0:9d5134074d84 247
JMF 0:9d5134074d84 248 return _temperature;
JMF 0:9d5134074d84 249 }