Diff: BME280.cpp

Revision:

5:7139d5accbc3

Parent:

4:ddcaa259e65b

Child:

6:d03826fe1062

--- a/BME280.cpp	Tue May 12 13:32:09 2015 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,192 +0,0 @@
-/**
- *  BME280 Combined humidity and pressure sensor library
- *
- *  @author  Toyomasa Watarai
- *  @version 1.0
- *  @date    06-April-2015
- *
- *  Library for "BME280 temperature, humidity and pressure sensor module" from Switch Science
- *    https://www.switch-science.com/catalog/2236/
- *
- *  For more information about the BME280:
- *    http://ae-bst.resource.bosch.com/media/products/dokumente/bme280/BST-BME280_DS001-10.pdf
- */
-
-#include "mbed.h"
-#include "BME280.h"
-
-BME280::BME280(PinName sda, PinName scl, char slave_adr)
-    :
-    i2c_p(new I2C(sda, scl)), 
-    i2c(*i2c_p),
-    address(slave_adr),
-    t_fine(0)
-{
-    initialize();
-}
-
-BME280::BME280(I2C &i2c_obj, char slave_adr)
-    :
-    i2c_p(NULL), 
-    i2c(i2c_obj),
-    address(slave_adr),
-    t_fine(0)
-{
-    initialize();
-}
-
-BME280::~BME280()
-{
-    if (NULL != i2c_p)
-        delete  i2c_p;
-}
-    
-void BME280::initialize()
-{
-    char cmd[18];
- 
-    cmd[0] = 0xf2; // ctrl_hum
-    cmd[1] = 0x01; // Humidity oversampling x1
-    i2c.write(address, cmd, 2);
- 
-    cmd[0] = 0xf4; // ctrl_meas
-    cmd[1] = 0x27; // Temparature oversampling x1, Pressure oversampling x1, Normal mode
-    i2c.write(address, cmd, 2);
- 
-    cmd[0] = 0xf5; // config
-    cmd[1] = 0xa0; // Standby 1000ms, Filter off
-    i2c.write(address, cmd, 2);
- 
-    cmd[0] = 0x88; // read dig_T regs
-    i2c.write(address, cmd, 1);
-    i2c.read(address, cmd, 6);
- 
-    dig_T1 = (cmd[1] << 8) | cmd[0];
-    dig_T2 = (cmd[3] << 8) | cmd[2];
-    dig_T3 = (cmd[5] << 8) | cmd[4];
- 
-    DEBUG_PRINT("dig_T = 0x%x, 0x%x, 0x%x\n", dig_T1, dig_T2, dig_T3);
- 
-    cmd[0] = 0x8E; // read dig_P regs
-    i2c.write(address, cmd, 1);
-    i2c.read(address, cmd, 18);
- 
-    dig_P1 = (cmd[ 1] << 8) | cmd[ 0];
-    dig_P2 = (cmd[ 3] << 8) | cmd[ 2];
-    dig_P3 = (cmd[ 5] << 8) | cmd[ 4];
-    dig_P4 = (cmd[ 7] << 8) | cmd[ 6];
-    dig_P5 = (cmd[ 9] << 8) | cmd[ 8];
-    dig_P6 = (cmd[11] << 8) | cmd[10];
-    dig_P7 = (cmd[13] << 8) | cmd[12];
-    dig_P8 = (cmd[15] << 8) | cmd[14];
-    dig_P9 = (cmd[17] << 8) | cmd[16];
- 
-    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);
- 
-    cmd[0] = 0xA1; // read dig_H regs
-    i2c.write(address, cmd, 1);
-    i2c.read(address, cmd, 1);
-     cmd[1] = 0xE1; // read dig_H regs
-    i2c.write(address, &cmd[1], 1);
-    i2c.read(address, &cmd[1], 7);
-
-    dig_H1 = cmd[0];
-    dig_H2 = (cmd[2] << 8) | cmd[1];
-    dig_H3 = cmd[3];
-    dig_H4 = (cmd[4] << 4) | (cmd[5] & 0x0f);
-    dig_H5 = (cmd[6] << 4) | ((cmd[5]>>4) & 0x0f);
-    dig_H6 = cmd[7];
- 
-    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);
-}
- 
-float BME280::getTemperature()
-{
-    uint32_t temp_raw;
-    float tempf;
-    char cmd[4];
- 
-    cmd[0] = 0xfa; // temp_msb
-    i2c.write(address, cmd, 1);
-    i2c.read(address, &cmd[1], 3);
- 
-    temp_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
- 
-    int32_t temp;
- 
-    temp =
-        (((((temp_raw >> 3) - (dig_T1 << 1))) * dig_T2) >> 11) +
-        ((((((temp_raw >> 4) - dig_T1) * ((temp_raw >> 4) - dig_T1)) >> 12) * dig_T3) >> 14);
- 
-    t_fine = temp;
-    temp = (temp * 5 + 128) >> 8;
-    tempf = (float)temp;
- 
-    return (tempf/100.0f);
-}
- 
-float BME280::getPressure()
-{
-    uint32_t press_raw;
-    float pressf;
-    char cmd[4];
- 
-    cmd[0] = 0xf7; // press_msb
-    i2c.write(address, cmd, 1);
-    i2c.read(address, &cmd[1], 3);
- 
-    press_raw = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
- 
-    int32_t var1, var2;
-    uint32_t press;
- 
-    var1 = (t_fine >> 1) - 64000;
-    var2 = (((var1 >> 2) * (var1 >> 2)) >> 11) * dig_P6;
-    var2 = var2 + ((var1 * dig_P5) << 1);
-    var2 = (var2 >> 2) + (dig_P4 << 16);
-    var1 = (((dig_P3 * (((var1 >> 2)*(var1 >> 2)) >> 13)) >> 3) + ((dig_P2 * var1) >> 1)) >> 18;
-    var1 = ((32768 + var1) * dig_P1) >> 15;
-    if (var1 == 0) {
-        return 0;
-    }
-    press = (((1048576 - press_raw) - (var2 >> 12))) * 3125;
-    if(press < 0x80000000) {
-        press = (press << 1) / var1;
-    } else {
-        press = (press / var1) * 2;
-    }
-    var1 = ((int32_t)dig_P9 * ((int32_t)(((press >> 3) * (press >> 3)) >> 13))) >> 12;
-    var2 = (((int32_t)(press >> 2)) * (int32_t)dig_P8) >> 13;
-    press = (press + ((var1 + var2 + dig_P7) >> 4));
- 
-    pressf = (float)press;
-    return (pressf/100.0f);
-}
- 
-float BME280::getHumidity()
-{
-    uint32_t hum_raw;
-    float humf;
-    char cmd[4];
- 
-    cmd[0] = 0xfd; // hum_msb
-    i2c.write(address, cmd, 1);
-    i2c.read(address, &cmd[1], 2);
- 
-    hum_raw = (cmd[1] << 8) | cmd[2];
- 
-    int32_t v_x1;
- 
-    v_x1 = t_fine - 76800;
-    v_x1 =  (((((hum_raw << 14) -(((int32_t)dig_H4) << 20) - (((int32_t)dig_H5) * v_x1)) +
-               ((int32_t)16384)) >> 15) * (((((((v_x1 * (int32_t)dig_H6) >> 10) *
-                                            (((v_x1 * ((int32_t)dig_H3)) >> 11) + 32768)) >> 10) + 2097152) *
-                                            (int32_t)dig_H2 + 8192) >> 14));
-    v_x1 = (v_x1 - (((((v_x1 >> 15) * (v_x1 >> 15)) >> 7) * (int32_t)dig_H1) >> 4));
-    v_x1 = (v_x1 < 0 ? 0 : v_x1);
-    v_x1 = (v_x1 > 419430400 ? 419430400 : v_x1);
- 
-    humf = (float)(v_x1 >> 12);
- 
-    return (humf/1024.0f);
-}