洸介 乾 / BME280

wakaranai

BME280.cpp@0:a399ad3155fb, 2016-11-01 (annotated)

Committer:
Calcium
Date:
Tue Nov 01 05:58:46 2016 +0000
Revision:
0:a399ad3155fb
fuck you

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Calcium 0:a399ad3155fb 1 /**
Calcium 0:a399ad3155fb 2 * BME280 Combined humidity and pressure sensor library
Calcium 0:a399ad3155fb 3 *
Calcium 0:a399ad3155fb 4 * @author Toyomasa Watarai
Calcium 0:a399ad3155fb 5 * @version 1.0
Calcium 0:a399ad3155fb 6 * @date 06-April-2015
Calcium 0:a399ad3155fb 7 *
Calcium 0:a399ad3155fb 8 * Library for "BME280 temperature, humidity and pressure sensor module" from Switch Science
Calcium 0:a399ad3155fb 9 * https://www.switch-science.com/catalog/2236/
Calcium 0:a399ad3155fb 10 *
Calcium 0:a399ad3155fb 11 * For more information about the BME280:
Calcium 0:a399ad3155fb 12 * http://ae-bst.resource.bosch.com/media/products/dokumente/bme280/BST-BME280_DS001-10.pdf
Calcium 0:a399ad3155fb 13 */
Calcium 0:a399ad3155fb 14
Calcium 0:a399ad3155fb 15 #include "mbed.h"
Calcium 0:a399ad3155fb 16 #include "BME280.h"
Calcium 0:a399ad3155fb 17
Calcium 0:a399ad3155fb 18 BME280::BME280(PinName sda, PinName scl, char slave_adr)
Calcium 0:a399ad3155fb 19 :
Calcium 0:a399ad3155fb 20 i2c_p(new I2C(sda, scl)),
Calcium 0:a399ad3155fb 21 i2c(*i2c_p),
Calcium 0:a399ad3155fb 22 address(slave_adr),
Calcium 0:a399ad3155fb 23 t_fine(0)
Calcium 0:a399ad3155fb 24 {
Calcium 0:a399ad3155fb 25 initialize();
Calcium 0:a399ad3155fb 26 }
Calcium 0:a399ad3155fb 27
Calcium 0:a399ad3155fb 28 BME280::BME280(I2C &i2c_obj, char slave_adr)
Calcium 0:a399ad3155fb 29 :
Calcium 0:a399ad3155fb 30 i2c_p(NULL),
Calcium 0:a399ad3155fb 31 i2c(i2c_obj),
Calcium 0:a399ad3155fb 32 address(slave_adr),
Calcium 0:a399ad3155fb 33 t_fine(0)
Calcium 0:a399ad3155fb 34 {
Calcium 0:a399ad3155fb 35 initialize();
Calcium 0:a399ad3155fb 36 }
Calcium 0:a399ad3155fb 37
Calcium 0:a399ad3155fb 38 BME280::~BME280()
Calcium 0:a399ad3155fb 39 {
Calcium 0:a399ad3155fb 40 if (NULL != i2c_p)
Calcium 0:a399ad3155fb 41 delete i2c_p;
Calcium 0:a399ad3155fb 42 }
Calcium 0:a399ad3155fb 43
Calcium 0:a399ad3155fb 44 void BME280::initialize()
Calcium 0:a399ad3155fb 45 {
Calcium 0:a399ad3155fb 46 char cmd[18];
Calcium 0:a399ad3155fb 47
Calcium 0:a399ad3155fb 48 cmd[0] = 0xf2; // ctrl_hum
Calcium 0:a399ad3155fb 49 cmd[1] = 0x01; // Humidity oversampling x1
Calcium 0:a399ad3155fb 50 i2c.write(address, cmd, 2);
Calcium 0:a399ad3155fb 51
Calcium 0:a399ad3155fb 52 cmd[0] = 0xf4; // ctrl_meas
Calcium 0:a399ad3155fb 53 cmd[1] = 0x27; // Temparature oversampling x1, Pressure oversampling x1, Normal mode
Calcium 0:a399ad3155fb 54 i2c.write(address, cmd, 2);
Calcium 0:a399ad3155fb 55
Calcium 0:a399ad3155fb 56 cmd[0] = 0xf5; // config
Calcium 0:a399ad3155fb 57 cmd[1] = 0xa0; // Standby 1000ms, Filter off
Calcium 0:a399ad3155fb 58 i2c.write(address, cmd, 2);
Calcium 0:a399ad3155fb 59
Calcium 0:a399ad3155fb 60 cmd[0] = 0x88; // read dig_T regs
Calcium 0:a399ad3155fb 61 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 62 i2c.read(address, cmd, 6);
Calcium 0:a399ad3155fb 63
Calcium 0:a399ad3155fb 64 dig_T1 = (cmd[1] << 8) | cmd[0];
Calcium 0:a399ad3155fb 65 dig_T2 = (cmd[3] << 8) | cmd[2];
Calcium 0:a399ad3155fb 66 dig_T3 = (cmd[5] << 8) | cmd[4];
Calcium 0:a399ad3155fb 67
Calcium 0:a399ad3155fb 68 DEBUG_PRINT("dig_T = 0x%x, 0x%x, 0x%x\n", dig_T1, dig_T2, dig_T3);
Calcium 0:a399ad3155fb 69
Calcium 0:a399ad3155fb 70 cmd[0] = 0x8E; // read dig_P regs
Calcium 0:a399ad3155fb 71 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 72 i2c.read(address, cmd, 18);
Calcium 0:a399ad3155fb 73
Calcium 0:a399ad3155fb 74 dig_P1 = (cmd[ 1] << 8) | cmd[ 0];
Calcium 0:a399ad3155fb 75 dig_P2 = (cmd[ 3] << 8) | cmd[ 2];
Calcium 0:a399ad3155fb 76 dig_P3 = (cmd[ 5] << 8) | cmd[ 4];
Calcium 0:a399ad3155fb 77 dig_P4 = (cmd[ 7] << 8) | cmd[ 6];
Calcium 0:a399ad3155fb 78 dig_P5 = (cmd[ 9] << 8) | cmd[ 8];
Calcium 0:a399ad3155fb 79 dig_P6 = (cmd[11] << 8) | cmd[10];
Calcium 0:a399ad3155fb 80 dig_P7 = (cmd[13] << 8) | cmd[12];
Calcium 0:a399ad3155fb 81 dig_P8 = (cmd[15] << 8) | cmd[14];
Calcium 0:a399ad3155fb 82 dig_P9 = (cmd[17] << 8) | cmd[16];
Calcium 0:a399ad3155fb 83
Calcium 0:a399ad3155fb 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);
Calcium 0:a399ad3155fb 85
Calcium 0:a399ad3155fb 86 cmd[0] = 0xA1; // read dig_H regs
Calcium 0:a399ad3155fb 87 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 88 i2c.read(address, cmd, 1);
Calcium 0:a399ad3155fb 89 cmd[1] = 0xE1; // read dig_H regs
Calcium 0:a399ad3155fb 90 i2c.write(address, &cmd[1], 1);
Calcium 0:a399ad3155fb 91 i2c.read(address, &cmd[1], 7);
Calcium 0:a399ad3155fb 92
Calcium 0:a399ad3155fb 93 dig_H1 = cmd[0];
Calcium 0:a399ad3155fb 94 dig_H2 = (cmd[2] << 8) | cmd[1];
Calcium 0:a399ad3155fb 95 dig_H3 = cmd[3];
Calcium 0:a399ad3155fb 96 dig_H4 = (cmd[4] << 4) | (cmd[5] & 0x0f);
Calcium 0:a399ad3155fb 97 dig_H5 = (cmd[6] << 4) | ((cmd[5]>>4) & 0x0f);
Calcium 0:a399ad3155fb 98 dig_H6 = cmd[7];
Calcium 0:a399ad3155fb 99
Calcium 0:a399ad3155fb 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);
Calcium 0:a399ad3155fb 101 }
Calcium 0:a399ad3155fb 102
Calcium 0:a399ad3155fb 103 float BME280::getTemperature()
Calcium 0:a399ad3155fb 104 {
Calcium 0:a399ad3155fb 105 uint32_t temp_raw;
Calcium 0:a399ad3155fb 106 float tempf;
Calcium 0:a399ad3155fb 107 char cmd[4];
Calcium 0:a399ad3155fb 108
Calcium 0:a399ad3155fb 109 cmd[0] = 0xfa; // temp_msb
Calcium 0:a399ad3155fb 110 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 111 i2c.read(address, &cmd[1], 3);
Calcium 0:a399ad3155fb 112
Calcium 0:a399ad3155fb 113 temp_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
Calcium 0:a399ad3155fb 114
Calcium 0:a399ad3155fb 115 int32_t temp;
Calcium 0:a399ad3155fb 116
Calcium 0:a399ad3155fb 117 temp =
Calcium 0:a399ad3155fb 118 (((((temp_raw >> 3) - (dig_T1 << 1))) * dig_T2) >> 11) +
Calcium 0:a399ad3155fb 119 ((((((temp_raw >> 4) - dig_T1) * ((temp_raw >> 4) - dig_T1)) >> 12) * dig_T3) >> 14);
Calcium 0:a399ad3155fb 120
Calcium 0:a399ad3155fb 121 t_fine = temp;
Calcium 0:a399ad3155fb 122 temp = (temp * 5 + 128) >> 8;
Calcium 0:a399ad3155fb 123 tempf = (float)temp;
Calcium 0:a399ad3155fb 124
Calcium 0:a399ad3155fb 125 return (tempf/100.0f);
Calcium 0:a399ad3155fb 126 }
Calcium 0:a399ad3155fb 127
Calcium 0:a399ad3155fb 128 float BME280::getPressure()
Calcium 0:a399ad3155fb 129 {
Calcium 0:a399ad3155fb 130 uint32_t press_raw;
Calcium 0:a399ad3155fb 131 float pressf;
Calcium 0:a399ad3155fb 132 char cmd[4];
Calcium 0:a399ad3155fb 133
Calcium 0:a399ad3155fb 134 cmd[0] = 0xf7; // press_msb
Calcium 0:a399ad3155fb 135 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 136 i2c.read(address, &cmd[1], 3);
Calcium 0:a399ad3155fb 137
Calcium 0:a399ad3155fb 138 press_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
Calcium 0:a399ad3155fb 139
Calcium 0:a399ad3155fb 140 int32_t var1, var2;
Calcium 0:a399ad3155fb 141 uint32_t press;
Calcium 0:a399ad3155fb 142
Calcium 0:a399ad3155fb 143 var1 = (t_fine >> 1) - 64000;
Calcium 0:a399ad3155fb 144 var2 = (((var1 >> 2) * (var1 >> 2)) >> 11) * dig_P6;
Calcium 0:a399ad3155fb 145 var2 = var2 + ((var1 * dig_P5) << 1);
Calcium 0:a399ad3155fb 146 var2 = (var2 >> 2) + (dig_P4 << 16);
Calcium 0:a399ad3155fb 147 var1 = (((dig_P3 * (((var1 >> 2)*(var1 >> 2)) >> 13)) >> 3) + ((dig_P2 * var1) >> 1)) >> 18;
Calcium 0:a399ad3155fb 148 var1 = ((32768 + var1) * dig_P1) >> 15;
Calcium 0:a399ad3155fb 149 if (var1 == 0) {
Calcium 0:a399ad3155fb 150 return 0;
Calcium 0:a399ad3155fb 151 }
Calcium 0:a399ad3155fb 152 press = (((1048576 - press_raw) - (var2 >> 12))) * 3125;
Calcium 0:a399ad3155fb 153 if(press < 0x80000000) {
Calcium 0:a399ad3155fb 154 press = (press << 1) / var1;
Calcium 0:a399ad3155fb 155 } else {
Calcium 0:a399ad3155fb 156 press = (press / var1) * 2;
Calcium 0:a399ad3155fb 157 }
Calcium 0:a399ad3155fb 158 var1 = ((int32_t)dig_P9 * ((int32_t)(((press >> 3) * (press >> 3)) >> 13))) >> 12;
Calcium 0:a399ad3155fb 159 var2 = (((int32_t)(press >> 2)) * (int32_t)dig_P8) >> 13;
Calcium 0:a399ad3155fb 160 press = (press + ((var1 + var2 + dig_P7) >> 4));
Calcium 0:a399ad3155fb 161
Calcium 0:a399ad3155fb 162 pressf = (float)press;
Calcium 0:a399ad3155fb 163 return (pressf/100.0f);
Calcium 0:a399ad3155fb 164 }
Calcium 0:a399ad3155fb 165
Calcium 0:a399ad3155fb 166 float BME280::getHumidity()
Calcium 0:a399ad3155fb 167 {
Calcium 0:a399ad3155fb 168 uint32_t hum_raw;
Calcium 0:a399ad3155fb 169 float humf;
Calcium 0:a399ad3155fb 170 char cmd[4];
Calcium 0:a399ad3155fb 171
Calcium 0:a399ad3155fb 172 cmd[0] = 0xfd; // hum_msb
Calcium 0:a399ad3155fb 173 i2c.write(address, cmd, 1);
Calcium 0:a399ad3155fb 174 i2c.read(address, &cmd[1], 2);
Calcium 0:a399ad3155fb 175
Calcium 0:a399ad3155fb 176 hum_raw = (cmd[1] << 8) | cmd[2];
Calcium 0:a399ad3155fb 177
Calcium 0:a399ad3155fb 178 int32_t v_x1;
Calcium 0:a399ad3155fb 179
Calcium 0:a399ad3155fb 180 v_x1 = t_fine - 76800;
Calcium 0:a399ad3155fb 181 v_x1 = (((((hum_raw << 14) -(((int32_t)dig_H4) << 20) - (((int32_t)dig_H5) * v_x1)) +
Calcium 0:a399ad3155fb 182 ((int32_t)16384)) >> 15) * (((((((v_x1 * (int32_t)dig_H6) >> 10) *
Calcium 0:a399ad3155fb 183 (((v_x1 * ((int32_t)dig_H3)) >> 11) + 32768)) >> 10) + 2097152) *
Calcium 0:a399ad3155fb 184 (int32_t)dig_H2 + 8192) >> 14));
Calcium 0:a399ad3155fb 185 v_x1 = (v_x1 - (((((v_x1 >> 15) * (v_x1 >> 15)) >> 7) * (int32_t)dig_H1) >> 4));
Calcium 0:a399ad3155fb 186 v_x1 = (v_x1 < 0 ? 0 : v_x1);
Calcium 0:a399ad3155fb 187 v_x1 = (v_x1 > 419430400 ? 419430400 : v_x1);
Calcium 0:a399ad3155fb 188
Calcium 0:a399ad3155fb 189 humf = (float)(v_x1 >> 12);
Calcium 0:a399ad3155fb 190
Calcium 0:a399ad3155fb 191 return (humf/1024.0f);
Calcium 0:a399ad3155fb 192 }