Paul Staron / BME280

OS6. i2s BME280 library, also works with BMP280 without Humidity. See BME280.h for example code.

BME280.h@0:19fab6c64964, 2021-01-02 (annotated)

Committer:
star297
Date:
Sat Jan 02 10:32:48 2021 +0000
Revision:
0:19fab6c64964
initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
star297 0:19fab6c64964 1 #ifndef BME_H
star297 0:19fab6c64964 2 #define BME_H
star297 0:19fab6c64964 3
star297 0:19fab6c64964 4 #include "mbed.h"
star297 0:19fab6c64964 5
star297 0:19fab6c64964 6 #define _debug 1 // '1' to enable prinf BME's registers
star297 0:19fab6c64964 7
star297 0:19fab6c64964 8 /*
star297 0:19fab6c64964 9 Bosch Sensortec BMP280 BME280 i2c example code
star297 0:19fab6c64964 10 using 64bit numeric calculations as recomended by Bosch.
star297 0:19fab6c64964 11 Some sensors supplied from Chinese suppliers may have 'suspect'
star297 0:19fab6c64964 12 quality sensor with different i2c address.
star297 0:19fab6c64964 13 My sensors were address 0xEC and all the ones I have
star297 0:19fab6c64964 14 differ quite a bit in tolerance :( so be aware if accuracy is paramount.
star297 0:19fab6c64964 15 */
star297 0:19fab6c64964 16
star297 0:19fab6c64964 17 /*
star297 0:19fab6c64964 18 #include "mbed.h"
star297 0:19fab6c64964 19 #include "BME280.h"
star297 0:19fab6c64964 20
star297 0:19fab6c64964 21 BME sensor(D0,D1, 0xEC); // sda, clk, 8bit address (NUCLEO-L432)
star297 0:19fab6c64964 22 DigitalOut led(LED1);
star297 0:19fab6c64964 23
star297 0:19fab6c64964 24 float temp, humidity, pressure, altitude;
star297 0:19fab6c64964 25
star297 0:19fab6c64964 26 int main()
star297 0:19fab6c64964 27 {
star297 0:19fab6c64964 28
star297 0:19fab6c64964 29 int BMPE_id = sensor.init(); // initialise and get sensor id
star297 0:19fab6c64964 30
star297 0:19fab6c64964 31 if(!BMPE_id) {
star297 0:19fab6c64964 32 printf("No sensor detected!!\n");
star297 0:19fab6c64964 33 while(1){
star297 0:19fab6c64964 34 led=!led;
star297 0:19fab6c64964 35 ThisThread::sleep_for(200ms);
star297 0:19fab6c64964 36 }
star297 0:19fab6c64964 37 }
star297 0:19fab6c64964 38
star297 0:19fab6c64964 39 if(_debug){ // set _debug to '1' to see BME's registers
star297 0:19fab6c64964 40 ThisThread::sleep_for(2s);
star297 0:19fab6c64964 41 }
star297 0:19fab6c64964 42
star297 0:19fab6c64964 43 while(1) {
star297 0:19fab6c64964 44 led=1;
star297 0:19fab6c64964 45 printf("\033[0m\033[2J\033[H------- BME280-BMP280 Sensor example -------\r\n\n");
star297 0:19fab6c64964 46 if(BMPE_id==0x60) {
star297 0:19fab6c64964 47 printf("BME280 detected id: 0x%x\n\n",BMPE_id);
star297 0:19fab6c64964 48 } else if(BMPE_id==0x58) {
star297 0:19fab6c64964 49 printf("BMP280 detected id: 0x%x\n\n",BMPE_id);
star297 0:19fab6c64964 50 }
star297 0:19fab6c64964 51
star297 0:19fab6c64964 52 temp = sensor.getTemperature();
star297 0:19fab6c64964 53
star297 0:19fab6c64964 54 printf("Temperature: %3.2f %cc \n",temp,0xb0);
star297 0:19fab6c64964 55
star297 0:19fab6c64964 56 if(sensor.chip_id==0x60) { // only BME has Humidity
star297 0:19fab6c64964 57 humidity = sensor.getHumidity();
star297 0:19fab6c64964 58 printf("Humidity: %2.2f %cRh \n", humidity,0x25);
star297 0:19fab6c64964 59 }
star297 0:19fab6c64964 60 pressure = sensor.getPressure();
star297 0:19fab6c64964 61 printf("Pressure: %4.2f mbar's \n\n",pressure);
star297 0:19fab6c64964 62
star297 0:19fab6c64964 63 altitude = 44330.0f*( 1.0f - pow((pressure/1013.25f), (1.0f/5.255f)))+18; // Calculate altitude in meters
star297 0:19fab6c64964 64 printf("Altitude: %3.1f meters %4.1f feet \r\n(Referenced to 1,013.25 millibars @ sea level) \r\n\n", altitude,altitude*3.2810f);
star297 0:19fab6c64964 65 led=0;
star297 0:19fab6c64964 66 ThisThread::sleep_for(1s);
star297 0:19fab6c64964 67 }
star297 0:19fab6c64964 68 }
star297 0:19fab6c64964 69 */
star297 0:19fab6c64964 70
star297 0:19fab6c64964 71 class BME
star297 0:19fab6c64964 72 {
star297 0:19fab6c64964 73 public:
star297 0:19fab6c64964 74
star297 0:19fab6c64964 75 BME(PinName sda, PinName scl, char slave_adr);
star297 0:19fab6c64964 76
star297 0:19fab6c64964 77 int init(void);
star297 0:19fab6c64964 78 int chipID(void);
star297 0:19fab6c64964 79 float getTemperature(void);
star297 0:19fab6c64964 80 float getPressure(void);
star297 0:19fab6c64964 81 float getHumidity(void);
star297 0:19fab6c64964 82
star297 0:19fab6c64964 83 uint16_t chip_id;
star297 0:19fab6c64964 84
star297 0:19fab6c64964 85 private:
star297 0:19fab6c64964 86
star297 0:19fab6c64964 87 I2C bme;
star297 0:19fab6c64964 88 void initialize(void);
star297 0:19fab6c64964 89 char address;
star297 0:19fab6c64964 90 uint16_t dig_T1;
star297 0:19fab6c64964 91 int16_t dig_T2, dig_T3;
star297 0:19fab6c64964 92 uint16_t dig_P1;
star297 0:19fab6c64964 93 int16_t dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9;
star297 0:19fab6c64964 94 uint16_t dig_H1, dig_H3;
star297 0:19fab6c64964 95 int16_t dig_H2, dig_H4, dig_H5, dig_H6;
star297 0:19fab6c64964 96 int32_t t_fine;
star297 0:19fab6c64964 97 bool dbg_on;
star297 0:19fab6c64964 98 };
star297 0:19fab6c64964 99 #endif // BME_H