Diff: BME280.h

Revision:

0:19fab6c64964

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/BME280.h	Sat Jan 02 10:32:48 2021 +0000
@@ -0,0 +1,99 @@
+#ifndef BME_H
+#define BME_H
+
+#include "mbed.h"
+
+#define _debug   1      // '1' to enable prinf BME's registers
+
+/*
+Bosch Sensortec BMP280 BME280 i2c example code
+using 64bit numeric calculations as recomended by Bosch.
+Some sensors supplied from Chinese suppliers may have 'suspect'
+quality sensor with different i2c address.
+My sensors were address 0xEC and all the ones I have
+differ quite a bit in tolerance :( so be aware if accuracy is paramount.
+*/
+
+/*
+#include "mbed.h"
+#include "BME280.h"
+
+BME sensor(D0,D1, 0xEC); // sda, clk, 8bit address (NUCLEO-L432)
+DigitalOut led(LED1);
+
+float temp, humidity, pressure, altitude;
+
+int main()
+{
+
+    int BMPE_id = sensor.init();    // initialise and get sensor id
+
+    if(!BMPE_id) {
+        printf("No sensor detected!!\n");
+        while(1){
+            led=!led;
+            ThisThread::sleep_for(200ms);
+        }
+    }
+     
+    if(_debug){ // set _debug to '1' to see BME's registers
+        ThisThread::sleep_for(2s);
+        }
+    
+    while(1) {
+        led=1;
+        printf("\033[0m\033[2J\033[H------- BME280-BMP280 Sensor example -------\r\n\n");
+        if(BMPE_id==0x60) {
+            printf("BME280 detected id: 0x%x\n\n",BMPE_id);
+        } else if(BMPE_id==0x58) {
+            printf("BMP280 detected id: 0x%x\n\n",BMPE_id);
+        }
+
+        temp = sensor.getTemperature();
+            
+        printf("Temperature: %3.2f %cc \n",temp,0xb0);
+
+        if(sensor.chip_id==0x60) {        // only BME has Humidity
+            humidity    = sensor.getHumidity();
+            printf("Humidity:    %2.2f %cRh \n", humidity,0x25);
+        }
+        pressure    = sensor.getPressure();
+        printf("Pressure:    %4.2f mbar's \n\n",pressure);
+
+        altitude = 44330.0f*( 1.0f - pow((pressure/1013.25f), (1.0f/5.255f)))+18;     // Calculate altitude in meters
+        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);
+        led=0;
+        ThisThread::sleep_for(1s);
+    }
+}
+*/
+
+class BME
+{
+public:
+
+    BME(PinName sda, PinName scl, char slave_adr);
+
+    int         init(void);
+    int         chipID(void);
+    float       getTemperature(void);
+    float       getPressure(void);
+    float       getHumidity(void);
+  
+    uint16_t    chip_id;
+
+private:
+
+    I2C         bme;
+    void        initialize(void);
+    char        address;
+    uint16_t    dig_T1;
+    int16_t     dig_T2, dig_T3;
+    uint16_t    dig_P1;
+    int16_t     dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9;
+    uint16_t    dig_H1, dig_H3;
+    int16_t     dig_H2, dig_H4, dig_H5, dig_H6;
+    int32_t     t_fine;
+    bool        dbg_on;
+};
+#endif // BME_H