shinichi satoh / Mbed 2 deprecated php_access_i2c

BME280 mbed i2c

Dependencies:   EthernetInterface HTTPClient mbed-rtos mbed

Fork of php_access by shinichi satoh

BME280.cpp@2:7cf2ef9c51da, 2016-07-28 (annotated)

Committer:
thursday1024
Date:
Thu Jul 28 22:55:30 2016 +0000
Revision:
2:7cf2ef9c51da
BME280 I2C

Who changed what in which revision?

UserRevisionLine numberNew contents of line
thursday1024 2:7cf2ef9c51da 1 /**
thursday1024 2:7cf2ef9c51da 2 * BME280 Combined humidity and pressure sensor library
thursday1024 2:7cf2ef9c51da 3 *
thursday1024 2:7cf2ef9c51da 4 * @author Toyomasa Watarai
thursday1024 2:7cf2ef9c51da 5 * @version 1.0
thursday1024 2:7cf2ef9c51da 6 * @date 06-April-2015
thursday1024 2:7cf2ef9c51da 7 *
thursday1024 2:7cf2ef9c51da 8 * Library for "BME280 temperature, humidity and pressure sensor module" from Switch Science
thursday1024 2:7cf2ef9c51da 9 * https://www.switch-science.com/catalog/2236/
thursday1024 2:7cf2ef9c51da 10 *
thursday1024 2:7cf2ef9c51da 11 * For more information about the BME280:
thursday1024 2:7cf2ef9c51da 12 * http://ae-bst.resource.bosch.com/media/products/dokumente/bme280/BST-BME280_DS001-10.pdf
thursday1024 2:7cf2ef9c51da 13 */
thursday1024 2:7cf2ef9c51da 14
thursday1024 2:7cf2ef9c51da 15 #include "mbed.h"
thursday1024 2:7cf2ef9c51da 16 #include "BME280.h"
thursday1024 2:7cf2ef9c51da 17
thursday1024 2:7cf2ef9c51da 18 BME280::BME280(PinName sda, PinName scl, char slave_adr)
thursday1024 2:7cf2ef9c51da 19 :
thursday1024 2:7cf2ef9c51da 20 i2c_p(new I2C(sda, scl)),
thursday1024 2:7cf2ef9c51da 21 i2c(*i2c_p),
thursday1024 2:7cf2ef9c51da 22 address(slave_adr),
thursday1024 2:7cf2ef9c51da 23 t_fine(0)
thursday1024 2:7cf2ef9c51da 24 {
thursday1024 2:7cf2ef9c51da 25 initialize();
thursday1024 2:7cf2ef9c51da 26 }
thursday1024 2:7cf2ef9c51da 27
thursday1024 2:7cf2ef9c51da 28 BME280::BME280(I2C &i2c_obj, char slave_adr)
thursday1024 2:7cf2ef9c51da 29 :
thursday1024 2:7cf2ef9c51da 30 i2c_p(NULL),
thursday1024 2:7cf2ef9c51da 31 i2c(i2c_obj),
thursday1024 2:7cf2ef9c51da 32 address(slave_adr),
thursday1024 2:7cf2ef9c51da 33 t_fine(0)
thursday1024 2:7cf2ef9c51da 34 {
thursday1024 2:7cf2ef9c51da 35 initialize();
thursday1024 2:7cf2ef9c51da 36 }
thursday1024 2:7cf2ef9c51da 37
thursday1024 2:7cf2ef9c51da 38 BME280::~BME280()
thursday1024 2:7cf2ef9c51da 39 {
thursday1024 2:7cf2ef9c51da 40 if (NULL != i2c_p)
thursday1024 2:7cf2ef9c51da 41 delete i2c_p;
thursday1024 2:7cf2ef9c51da 42 }
thursday1024 2:7cf2ef9c51da 43
thursday1024 2:7cf2ef9c51da 44 void BME280::initialize()
thursday1024 2:7cf2ef9c51da 45 {
thursday1024 2:7cf2ef9c51da 46 char cmd[18];
thursday1024 2:7cf2ef9c51da 47
thursday1024 2:7cf2ef9c51da 48 cmd[0] = 0xf2; // ctrl_hum
thursday1024 2:7cf2ef9c51da 49 cmd[1] = 0x01; // Humidity oversampling x1
thursday1024 2:7cf2ef9c51da 50 i2c.write(address, cmd, 2);
thursday1024 2:7cf2ef9c51da 51
thursday1024 2:7cf2ef9c51da 52 cmd[0] = 0xf4; // ctrl_meas
thursday1024 2:7cf2ef9c51da 53 cmd[1] = 0x27; // Temparature oversampling x1, Pressure oversampling x1, Normal mode
thursday1024 2:7cf2ef9c51da 54 i2c.write(address, cmd, 2);
thursday1024 2:7cf2ef9c51da 55
thursday1024 2:7cf2ef9c51da 56 cmd[0] = 0xf5; // config
thursday1024 2:7cf2ef9c51da 57 cmd[1] = 0xa0; // Standby 1000ms, Filter off
thursday1024 2:7cf2ef9c51da 58 i2c.write(address, cmd, 2);
thursday1024 2:7cf2ef9c51da 59
thursday1024 2:7cf2ef9c51da 60 cmd[0] = 0x88; // read dig_T regs
thursday1024 2:7cf2ef9c51da 61 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 62 i2c.read(address, cmd, 6);
thursday1024 2:7cf2ef9c51da 63
thursday1024 2:7cf2ef9c51da 64 dig_T1 = (cmd[1] << 8) | cmd[0];
thursday1024 2:7cf2ef9c51da 65 dig_T2 = (cmd[3] << 8) | cmd[2];
thursday1024 2:7cf2ef9c51da 66 dig_T3 = (cmd[5] << 8) | cmd[4];
thursday1024 2:7cf2ef9c51da 67
thursday1024 2:7cf2ef9c51da 68 DEBUG_PRINT("dig_T = 0x%x, 0x%x, 0x%x\n", dig_T1, dig_T2, dig_T3);
thursday1024 2:7cf2ef9c51da 69
thursday1024 2:7cf2ef9c51da 70 cmd[0] = 0x8E; // read dig_P regs
thursday1024 2:7cf2ef9c51da 71 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 72 i2c.read(address, cmd, 18);
thursday1024 2:7cf2ef9c51da 73
thursday1024 2:7cf2ef9c51da 74 dig_P1 = (cmd[ 1] << 8) | cmd[ 0];
thursday1024 2:7cf2ef9c51da 75 dig_P2 = (cmd[ 3] << 8) | cmd[ 2];
thursday1024 2:7cf2ef9c51da 76 dig_P3 = (cmd[ 5] << 8) | cmd[ 4];
thursday1024 2:7cf2ef9c51da 77 dig_P4 = (cmd[ 7] << 8) | cmd[ 6];
thursday1024 2:7cf2ef9c51da 78 dig_P5 = (cmd[ 9] << 8) | cmd[ 8];
thursday1024 2:7cf2ef9c51da 79 dig_P6 = (cmd[11] << 8) | cmd[10];
thursday1024 2:7cf2ef9c51da 80 dig_P7 = (cmd[13] << 8) | cmd[12];
thursday1024 2:7cf2ef9c51da 81 dig_P8 = (cmd[15] << 8) | cmd[14];
thursday1024 2:7cf2ef9c51da 82 dig_P9 = (cmd[17] << 8) | cmd[16];
thursday1024 2:7cf2ef9c51da 83
thursday1024 2:7cf2ef9c51da 84 DEBUG_PRINT("dig_P = 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n", dig_P1, dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9);
thursday1024 2:7cf2ef9c51da 85
thursday1024 2:7cf2ef9c51da 86 cmd[0] = 0xA1; // read dig_H regs
thursday1024 2:7cf2ef9c51da 87 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 88 i2c.read(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 89 cmd[1] = 0xE1; // read dig_H regs
thursday1024 2:7cf2ef9c51da 90 i2c.write(address, &cmd[1], 1);
thursday1024 2:7cf2ef9c51da 91 i2c.read(address, &cmd[1], 7);
thursday1024 2:7cf2ef9c51da 92
thursday1024 2:7cf2ef9c51da 93 dig_H1 = cmd[0];
thursday1024 2:7cf2ef9c51da 94 dig_H2 = (cmd[2] << 8) | cmd[1];
thursday1024 2:7cf2ef9c51da 95 dig_H3 = cmd[3];
thursday1024 2:7cf2ef9c51da 96 dig_H4 = (cmd[4] << 4) | (cmd[5] & 0x0f);
thursday1024 2:7cf2ef9c51da 97 dig_H5 = (cmd[6] << 4) | ((cmd[5]>>4) & 0x0f);
thursday1024 2:7cf2ef9c51da 98 dig_H6 = cmd[7];
thursday1024 2:7cf2ef9c51da 99
thursday1024 2:7cf2ef9c51da 100 DEBUG_PRINT("dig_H = 0x%x, 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n", dig_H1, dig_H2, dig_H3, dig_H4, dig_H5, dig_H6);
thursday1024 2:7cf2ef9c51da 101 }
thursday1024 2:7cf2ef9c51da 102
thursday1024 2:7cf2ef9c51da 103 float BME280::getTemperature()
thursday1024 2:7cf2ef9c51da 104 {
thursday1024 2:7cf2ef9c51da 105 uint32_t temp_raw;
thursday1024 2:7cf2ef9c51da 106 float tempf;
thursday1024 2:7cf2ef9c51da 107 char cmd[4];
thursday1024 2:7cf2ef9c51da 108
thursday1024 2:7cf2ef9c51da 109 cmd[0] = 0xfa; // temp_msb
thursday1024 2:7cf2ef9c51da 110 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 111 i2c.read(address, &cmd[1], 3);
thursday1024 2:7cf2ef9c51da 112
thursday1024 2:7cf2ef9c51da 113 temp_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
thursday1024 2:7cf2ef9c51da 114
thursday1024 2:7cf2ef9c51da 115 int32_t temp;
thursday1024 2:7cf2ef9c51da 116
thursday1024 2:7cf2ef9c51da 117 temp =
thursday1024 2:7cf2ef9c51da 118 (((((temp_raw >> 3) - (dig_T1 << 1))) * dig_T2) >> 11) +
thursday1024 2:7cf2ef9c51da 119 ((((((temp_raw >> 4) - dig_T1) * ((temp_raw >> 4) - dig_T1)) >> 12) * dig_T3) >> 14);
thursday1024 2:7cf2ef9c51da 120
thursday1024 2:7cf2ef9c51da 121 t_fine = temp;
thursday1024 2:7cf2ef9c51da 122 temp = (temp * 5 + 128) >> 8;
thursday1024 2:7cf2ef9c51da 123 tempf = (float)temp;
thursday1024 2:7cf2ef9c51da 124
thursday1024 2:7cf2ef9c51da 125 return (tempf/100.0f);
thursday1024 2:7cf2ef9c51da 126 }
thursday1024 2:7cf2ef9c51da 127
thursday1024 2:7cf2ef9c51da 128 float BME280::getPressure()
thursday1024 2:7cf2ef9c51da 129 {
thursday1024 2:7cf2ef9c51da 130 uint32_t press_raw;
thursday1024 2:7cf2ef9c51da 131 float pressf;
thursday1024 2:7cf2ef9c51da 132 char cmd[4];
thursday1024 2:7cf2ef9c51da 133
thursday1024 2:7cf2ef9c51da 134 cmd[0] = 0xf7; // press_msb
thursday1024 2:7cf2ef9c51da 135 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 136 i2c.read(address, &cmd[1], 3);
thursday1024 2:7cf2ef9c51da 137
thursday1024 2:7cf2ef9c51da 138 press_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
thursday1024 2:7cf2ef9c51da 139
thursday1024 2:7cf2ef9c51da 140 int32_t var1, var2;
thursday1024 2:7cf2ef9c51da 141 uint32_t press;
thursday1024 2:7cf2ef9c51da 142
thursday1024 2:7cf2ef9c51da 143 var1 = (t_fine >> 1) - 64000;
thursday1024 2:7cf2ef9c51da 144 var2 = (((var1 >> 2) * (var1 >> 2)) >> 11) * dig_P6;
thursday1024 2:7cf2ef9c51da 145 var2 = var2 + ((var1 * dig_P5) << 1);
thursday1024 2:7cf2ef9c51da 146 var2 = (var2 >> 2) + (dig_P4 << 16);
thursday1024 2:7cf2ef9c51da 147 var1 = (((dig_P3 * (((var1 >> 2)*(var1 >> 2)) >> 13)) >> 3) + ((dig_P2 * var1) >> 1)) >> 18;
thursday1024 2:7cf2ef9c51da 148 var1 = ((32768 + var1) * dig_P1) >> 15;
thursday1024 2:7cf2ef9c51da 149 if (var1 == 0) {
thursday1024 2:7cf2ef9c51da 150 return 0;
thursday1024 2:7cf2ef9c51da 151 }
thursday1024 2:7cf2ef9c51da 152 press = (((1048576 - press_raw) - (var2 >> 12))) * 3125;
thursday1024 2:7cf2ef9c51da 153 if(press < 0x80000000) {
thursday1024 2:7cf2ef9c51da 154 press = (press << 1) / var1;
thursday1024 2:7cf2ef9c51da 155 } else {
thursday1024 2:7cf2ef9c51da 156 press = (press / var1) * 2;
thursday1024 2:7cf2ef9c51da 157 }
thursday1024 2:7cf2ef9c51da 158 var1 = ((int32_t)dig_P9 * ((int32_t)(((press >> 3) * (press >> 3)) >> 13))) >> 12;
thursday1024 2:7cf2ef9c51da 159 var2 = (((int32_t)(press >> 2)) * (int32_t)dig_P8) >> 13;
thursday1024 2:7cf2ef9c51da 160 press = (press + ((var1 + var2 + dig_P7) >> 4));
thursday1024 2:7cf2ef9c51da 161
thursday1024 2:7cf2ef9c51da 162 pressf = (float)press;
thursday1024 2:7cf2ef9c51da 163 return (pressf/100.0f);
thursday1024 2:7cf2ef9c51da 164 }
thursday1024 2:7cf2ef9c51da 165
thursday1024 2:7cf2ef9c51da 166 float BME280::getHumidity()
thursday1024 2:7cf2ef9c51da 167 {
thursday1024 2:7cf2ef9c51da 168 uint32_t hum_raw;
thursday1024 2:7cf2ef9c51da 169 float humf;
thursday1024 2:7cf2ef9c51da 170 char cmd[4];
thursday1024 2:7cf2ef9c51da 171
thursday1024 2:7cf2ef9c51da 172 cmd[0] = 0xfd; // hum_msb
thursday1024 2:7cf2ef9c51da 173 i2c.write(address, cmd, 1);
thursday1024 2:7cf2ef9c51da 174 i2c.read(address, &cmd[1], 2);
thursday1024 2:7cf2ef9c51da 175
thursday1024 2:7cf2ef9c51da 176 hum_raw = (cmd[1] << 8) | cmd[2];
thursday1024 2:7cf2ef9c51da 177
thursday1024 2:7cf2ef9c51da 178 int32_t v_x1;
thursday1024 2:7cf2ef9c51da 179
thursday1024 2:7cf2ef9c51da 180 v_x1 = t_fine - 76800;
thursday1024 2:7cf2ef9c51da 181 v_x1 = (((((hum_raw << 14) -(((int32_t)dig_H4) << 20) - (((int32_t)dig_H5) * v_x1)) +
thursday1024 2:7cf2ef9c51da 182 ((int32_t)16384)) >> 15) * (((((((v_x1 * (int32_t)dig_H6) >> 10) *
thursday1024 2:7cf2ef9c51da 183 (((v_x1 * ((int32_t)dig_H3)) >> 11) + 32768)) >> 10) + 2097152) *
thursday1024 2:7cf2ef9c51da 184 (int32_t)dig_H2 + 8192) >> 14));
thursday1024 2:7cf2ef9c51da 185 v_x1 = (v_x1 - (((((v_x1 >> 15) * (v_x1 >> 15)) >> 7) * (int32_t)dig_H1) >> 4));
thursday1024 2:7cf2ef9c51da 186 v_x1 = (v_x1 < 0 ? 0 : v_x1);
thursday1024 2:7cf2ef9c51da 187 v_x1 = (v_x1 > 419430400 ? 419430400 : v_x1);
thursday1024 2:7cf2ef9c51da 188
thursday1024 2:7cf2ef9c51da 189 humf = (float)(v_x1 >> 12);
thursday1024 2:7cf2ef9c51da 190
thursday1024 2:7cf2ef9c51da 191 return (humf/1024.0f);
thursday1024 2:7cf2ef9c51da 192 }
thursday1024 2:7cf2ef9c51da 193