Pierre Provent / Mbed 2 deprecated Test_Barometre_BME280_NUCLEO_F429ZI

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependencies:   mbed

BME280.cpp@3:87add4547c4e, 2020-12-18 (annotated)

Committer:
pierreprovent
Date:
Fri Dec 18 17:25:46 2020 +0000
Revision:
3:87add4547c4e
Parent:
2:6ff57cf56fe1 
sans modif

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pierreprovent 1:5d994dea50ef 1 #include "mbed.h"
pierreprovent 1:5d994dea50ef 2 #include "BME280.h"
pierreprovent 1:5d994dea50ef 3
pierreprovent 1:5d994dea50ef 4 BME280::BME280(PinName sda, PinName scl):i2c(sda, scl)
pierreprovent 1:5d994dea50ef 5 {
pierreprovent 1:5d994dea50ef 6 init();
pierreprovent 1:5d994dea50ef 7 read_calibration_data() ;
pierreprovent 1:5d994dea50ef 8 }
pierreprovent 1:5d994dea50ef 9
pierreprovent 1:5d994dea50ef 10 void BME280::init()
pierreprovent 1:5d994dea50ef 11 {
pierreprovent 1:5d994dea50ef 12 // Configuration de la mesure de température, pression et humidité
pierreprovent 1:5d994dea50ef 13 // Mode ""normal" pour des mesures régulières et précises de P, T, H.
pierreprovent 1:5d994dea50ef 14 // T et P filtrées par IIR et suréchantillonnage
pierreprovent 1:5d994dea50ef 15 // Choix d'un mode "indoor navigation" p 17-18 doc constructeur
pierreprovent 1:5d994dea50ef 16 // Registres : ctrl_hum osrs_h[2:0] = 001 oversampling humidity x1
pierreprovent 1:5d994dea50ef 17 // ctrl_hum = 00000 001
pierreprovent 1:5d994dea50ef 18 // ctrl_meas osrs_t[2:0] = 010 oversampling temperature x2
pierreprovent 1:5d994dea50ef 19 // ctrl_meas osrs_p[2:0] = 101 oversampling pressure x16
pierreprovent 1:5d994dea50ef 20 // ctrl_meas mode[1:0] = 11 Normal mode
pierreprovent 1:5d994dea50ef 21 // ctrl_meas = 010 101 11
pierreprovent 1:5d994dea50ef 22 // config t_sb[2:0] = 000 t_standby 0.5 ms
pierreprovent 1:5d994dea50ef 23 // config filter[2:0] = 100 filtre IIR à 16 coefficients
pierreprovent 1:5d994dea50ef 24 // config = 000 100 00
pierreprovent 1:5d994dea50ef 25 data_write[0] = BME280_CTRL_HUM_ADDR ;
pierreprovent 3:87add4547c4e 26 data_write[1] = ??????????? ;
pierreprovent 1:5d994dea50ef 27 i2c.write(BME280_ADDRESS, data_write, 2);
pierreprovent 1:5d994dea50ef 28 data_write[0] = BME280_CTRL_MEAS_ADDR ;
pierreprovent 3:87add4547c4e 29 data_write[1] = ?????????? ;
pierreprovent 1:5d994dea50ef 30 i2c.write(BME280_ADDRESS, data_write, 2);
pierreprovent 1:5d994dea50ef 31 data_write[0] = BME280_CONFIG_ADDR ;
pierreprovent 3:87add4547c4e 32 data_write[1] = ??????????? ;
pierreprovent 1:5d994dea50ef 33 i2c.write(BME280_ADDRESS, data_write, 2);
pierreprovent 1:5d994dea50ef 34 }
pierreprovent 1:5d994dea50ef 35
pierreprovent 1:5d994dea50ef 36 void BME280::read_calibration_data()
pierreprovent 1:5d994dea50ef 37 {
pierreprovent 1:5d994dea50ef 38 //Lecture des données de calibration de température et de pression du capteur
pierreprovent 1:5d994dea50ef 39 // 3 mots de 16 bits pour la température
pierreprovent 1:5d994dea50ef 40 // 9 mots de 16 bits pour la pression
pierreprovent 1:5d994dea50ef 41 // p 22-23
pierreprovent 1:5d994dea50ef 42 // Démarre la lecture à partir de l'adresse BME280_REG_DIG_T1 0x88
pierreprovent 1:5d994dea50ef 43 // Jusqu'à l'adresse BME280_REG_DIG_P9 0x9E
pierreprovent 1:5d994dea50ef 44 // Lecture des 24 octets en une seule fois
pierreprovent 1:5d994dea50ef 45 // 8 bits LSB en premier dans data_read[0], 8 bits MSB en second dans data_read[1] ;
pierreprovent 1:5d994dea50ef 46 // Et lecture de 2 octets supplémentaires, adresse 0xA0 et 0xA1
pierreprovent 1:5d994dea50ef 47 // 0xA1 contient une donnée de calibration pour l'humidité
pierreprovent 1:5d994dea50ef 48 // Les 7 autres octets de calibration d'humidité seront lus après de l'adresse 0xE1 à 0xE7
pierreprovent 1:5d994dea50ef 49
pierreprovent 1:5d994dea50ef 50 data_write[0] = BME280_REG_DIG_T1 ;
pierreprovent 1:5d994dea50ef 51 i2c.write(BME280_ADDRESS, data_write, 1);
pierreprovent 1:5d994dea50ef 52 i2c.read(BME280_ADDRESS, data_read, 26);
pierreprovent 1:5d994dea50ef 53
pierreprovent 1:5d994dea50ef 54 dig_T1 = (uint16_t) ( (uint16_t) (data_read[1] << 8) | (uint16_t) data_read[0] ) ;
pierreprovent 1:5d994dea50ef 55 dig_T2 = (int16_t) ( (int16_t) (data_read[3] << 8) | (int16_t) data_read[2] ) ;
pierreprovent 1:5d994dea50ef 56 dig_T3 = (int16_t) ( (int16_t) (data_read[5] << 8) | (int16_t) data_read[4] ) ;
pierreprovent 1:5d994dea50ef 57 dig_P1 = (uint16_t) ( (uint16_t) (data_read[7] << 8) | (uint16_t) data_read[6] ) ;
pierreprovent 1:5d994dea50ef 58 dig_P2 = (int16_t) ( (int16_t) (data_read[9] << 8) | (int16_t) data_read[8] ) ;
pierreprovent 1:5d994dea50ef 59 dig_P3 = (int16_t) ( (int16_t) (data_read[11] << 8) | (int16_t) data_read[10] ) ;
pierreprovent 1:5d994dea50ef 60 dig_P4 = (int16_t) ( (int16_t) (data_read[13] << 8) | (int16_t) data_read[12] ) ;
pierreprovent 1:5d994dea50ef 61 dig_P5 = (int16_t) ( (int16_t) (data_read[15] << 8) | (int16_t) data_read[14] ) ;
pierreprovent 1:5d994dea50ef 62 dig_P6 = (int16_t) ( (int16_t) (data_read[17] << 8) | (int16_t) data_read[16] ) ;
pierreprovent 1:5d994dea50ef 63 dig_P7 = (int16_t) ( (int16_t) (data_read[19] << 8) | (int16_t) data_read[18] ) ;
pierreprovent 1:5d994dea50ef 64 dig_P8 = (int16_t) ( (int16_t) (data_read[21] << 8) | (int16_t) data_read[20] ) ;
pierreprovent 1:5d994dea50ef 65 dig_P9 = (int16_t) ( (int16_t) (data_read[23] << 8) | (int16_t) data_read[22] ) ;
pierreprovent 1:5d994dea50ef 66 dig_H1 = (uint8_t) data_read[25] ;
pierreprovent 1:5d994dea50ef 67
pierreprovent 1:5d994dea50ef 68 //Lecture des données de calibration d'humidité
pierreprovent 1:5d994dea50ef 69 // 7 octets de l'adresse 0xE1 à 0xE7
pierreprovent 1:5d994dea50ef 70 data_write[0] = BME280_REG_DIG_H2 ;
pierreprovent 1:5d994dea50ef 71 i2c.write(BME280_ADDRESS, data_write, 1);
pierreprovent 1:5d994dea50ef 72 i2c.read(BME280_ADDRESS, data_read, 7);
pierreprovent 1:5d994dea50ef 73
pierreprovent 1:5d994dea50ef 74 dig_H2 = (int16_t) ( (int16_t) (data_read[1] << 8) | (int16_t) data_read[0] ) ;
pierreprovent 1:5d994dea50ef 75 dig_H3 = (uint8_t) data_read[2] ;
pierreprovent 1:5d994dea50ef 76 dig_H4 = (int16_t) ( (int16_t) (data_read[4] & 0x0F) | (int16_t) data_read[3] *16 ) ;
pierreprovent 1:5d994dea50ef 77 dig_H5 = (int16_t) ( ((int16_t) data_read[5] * 16 | (int16_t) data_read[4]) >> 4 ) ;
pierreprovent 1:5d994dea50ef 78 dig_H6 = (int8_t) data_read[6] ;
pierreprovent 1:5d994dea50ef 79 }
pierreprovent 1:5d994dea50ef 80
pierreprovent 1:5d994dea50ef 81 double BME280::temperature()
pierreprovent 1:5d994dea50ef 82 {
pierreprovent 1:5d994dea50ef 83 double temperature ; // Température en double précision
pierreprovent 1:5d994dea50ef 84 int32_t temp_32bits;
pierreprovent 1:5d994dea50ef 85
pierreprovent 1:5d994dea50ef 86 data_write[0] = BME280_REG_TEMPDATA ;
pierreprovent 1:5d994dea50ef 87 i2c.write(BME280_ADDRESS, data_write, 1);
pierreprovent 1:5d994dea50ef 88 i2c.read(BME280_ADDRESS, data_read, 3);
pierreprovent 1:5d994dea50ef 89 temp_32bits = (int32_t) ( ((int32_t) data_read[0] << 12 | (int32_t) data_read[1] << 4 | (int16_t) data_read[2] >> 4) ) ;
pierreprovent 1:5d994dea50ef 90 var1 = (((double) temp_32bits) / 16384.0 - ((double) dig_T1) / 1024.0) * ((double)dig_T2) ;
pierreprovent 1:5d994dea50ef 91 var2 = ((((double) temp_32bits) / 131072.0 - ((double) dig_T1) / 8192.0) *
pierreprovent 1:5d994dea50ef 92 (((double) temp_32bits) / 131072.0 - ((double) dig_T1) / 8192.0)) *
pierreprovent 1:5d994dea50ef 93 ((double) dig_T3);
pierreprovent 1:5d994dea50ef 94 temperature = ((var1 + var2) / 5120.0);
pierreprovent 1:5d994dea50ef 95 t_fine = (int32_t) (var1 + var2);
pierreprovent 1:5d994dea50ef 96 return temperature ;
pierreprovent 1:5d994dea50ef 97 }
pierreprovent 1:5d994dea50ef 98
pierreprovent 1:5d994dea50ef 99 double BME280::pression()
pierreprovent 1:5d994dea50ef 100 {
pierreprovent 1:5d994dea50ef 101 double pression ; // Pression en double precision
pierreprovent 1:5d994dea50ef 102 int32_t press_32bits;
pierreprovent 1:5d994dea50ef 103
pierreprovent 1:5d994dea50ef 104 data_write[0] = BME280_REG_PRESSUREDATA ;
pierreprovent 1:5d994dea50ef 105 i2c.write(BME280_ADDRESS, data_write, 1);
pierreprovent 1:5d994dea50ef 106 i2c.read(BME280_ADDRESS, data_read, 3);
pierreprovent 1:5d994dea50ef 107 press_32bits = (int32_t) ( ((int32_t) data_read[0] << 12 | (int32_t) data_read[1] << 4 | (int16_t) data_read[2] >> 4) ) ;
pierreprovent 1:5d994dea50ef 108 var1 = ((double) t_fine / 2.0) - 64000.0;
pierreprovent 1:5d994dea50ef 109 var2 = var1 * var1 * ((double) dig_P6) / 32768.0;
pierreprovent 1:5d994dea50ef 110 var2 = var2 + var1 * ((double) dig_P5) * 2.0;
pierreprovent 1:5d994dea50ef 111 var2 = (var2 / 4.0) + (((double) dig_P4) * 65536.0);
pierreprovent 1:5d994dea50ef 112 var1 = (((double) dig_P3) * var1 * var1 / 524288.0 + ((double) dig_P2) * var1) /
pierreprovent 1:5d994dea50ef 113 524288.0;
pierreprovent 1:5d994dea50ef 114 var1 = (1.0 + var1 / 32768.0) * ((double) dig_P1);
pierreprovent 1:5d994dea50ef 115 if (var1 == 0.0)
pierreprovent 1:5d994dea50ef 116 return 0; // avoid exception caused by division by zero
pierreprovent 1:5d994dea50ef 117 pression = 1048576.0 - (double)press_32bits ;
pierreprovent 1:5d994dea50ef 118 pression = (pression-(var2/4096.0))* 6250.0/var1;
pierreprovent 1:5d994dea50ef 119 var1 = ((double) dig_P9) * pression * pression / 2147483648.0;
pierreprovent 1:5d994dea50ef 120 var2 = pression * ((double) dig_P8) / 32768.0;
pierreprovent 1:5d994dea50ef 121 pression = pression + (var1 + var2 + ((double) dig_P7)) / 16.0;
pierreprovent 1:5d994dea50ef 122 return pression ;
pierreprovent 1:5d994dea50ef 123 }
pierreprovent 1:5d994dea50ef 124
pierreprovent 1:5d994dea50ef 125 double BME280::humidite()
pierreprovent 1:5d994dea50ef 126 {
pierreprovent 1:5d994dea50ef 127 double humidite ; // Humidite en double precision
pierreprovent 1:5d994dea50ef 128 int32_t hum_32bits;
pierreprovent 1:5d994dea50ef 129 data_write[0] = BME280_REG_HUMDATA ;
pierreprovent 1:5d994dea50ef 130 i2c.write(BME280_ADDRESS, data_write, 1);
pierreprovent 1:5d994dea50ef 131 i2c.read(BME280_ADDRESS, data_read, 2);
pierreprovent 1:5d994dea50ef 132 hum_32bits = (int32_t) ( ((int32_t) data_read[0] << 8 | (int32_t) data_read[1] ) ) ;
pierreprovent 1:5d994dea50ef 133 humidite = (double)t_fine - 76800.0;
pierreprovent 1:5d994dea50ef 134 humidite = (hum_32bits - (((double)dig_H4) * 64.0 + ((double)dig_H5) / 16384.0 * humidite)) *
pierreprovent 1:5d994dea50ef 135 (((double)dig_H2) / 65536.0 * (1.0 + ((double)dig_H6) / 67108864.0 * humidite *
pierreprovent 1:5d994dea50ef 136 (1.0 + ((double)dig_H3) / 67108864.0 * humidite)));
pierreprovent 1:5d994dea50ef 137 humidite = humidite * (1.0 - ((double)dig_H1) * humidite / 524288.0);
pierreprovent 1:5d994dea50ef 138 if (humidite > 100.0)
pierreprovent 1:5d994dea50ef 139 humidite = 100.0;
pierreprovent 1:5d994dea50ef 140 else if (humidite < 0.0)
pierreprovent 1:5d994dea50ef 141 humidite = 0.0;
pierreprovent 1:5d994dea50ef 142 return humidite;
pierreprovent 1:5d994dea50ef 143 }