BME280_SPI.h

00001 /**
00002  ******************************************************************************
00003  * @file    BME280_SPI.h
00004  * @author  Toyomasa Watarai
00005  * @version V1.0.0
00006  * @date    11 March 2017
00007  * @brief   This file contains the class of a BME280 Combined humidity and pressure sensor library with SPI interface
00008  ******************************************************************************
00009  * @attention
00010  *
00011  * Licensed under the Apache License, Version 2.0 (the "License");
00012  * you may not use this file except in compliance with the License.
00013  * You may obtain a copy of the License at
00014  *
00015  *     http://www.apache.org/licenses/LICENSE-2.0
00016  *
00017  * Unless required by applicable law or agreed to in writing, software
00018  * distributed under the License is distributed on an "AS IS" BASIS,
00019  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020  * See the License for the specific language governing permissions and
00021  * limitations under the License.
00022  */
00023 
00024 /**
00025  *  Library for "BME280 temperature, humidity and pressure sensor module" from Switch Science
00026  *    https://www.switch-science.com/catalog/2236/
00027  *
00028  *  For more information about the BME280:
00029  *    https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
00030 */
00031 
00032 #ifndef MBED_BME280_SPI_H
00033 #define MBED_BME280_SPI_H
00034 
00035 #include "mbed.h"
00036 
00037 #ifdef _DEBUG
00038 extern Serial pc;
00039 #define DEBUG_PRINT(...) pc.printf(__VA_ARGS__)
00040 #else
00041 #define DEBUG_PRINT(...)
00042 #endif
00043 
00044 /**  Interface for controlling BME280 Combined humidity and pressure sensor
00045  *
00046  * @code
00047  * #include "mbed.h"
00048  * #include "BME280_SPI.h"
00049  *
00050  * Serial pc(USBTX, USBRX);
00051  * BME280_SPI sensor(D11, D12, D13, D9); // mosi, miso, sclk, cs
00052  *
00053  * int main() {
00054  *
00055  *     while(1) {
00056  *         pc.printf("%2.2f degC, %04.2f hPa, %2.2f %%\n", sensor.getTemperature(), sensor.getPressure(), sensor.getHumidity());
00057  *         wait(1);
00058  *     }
00059  * }
00060  *
00061  * @endcode
00062  */
00063 
00064 /** BME280_SPI class
00065  *
00066  *  BME280_SPI: A library to correct environmental data using Boshe BME280 environmental sensor device
00067  *
00068  */
00069 class BME280_SPI
00070 {
00071 public:
00072 
00073     enum spi_mask {
00074         BME280_SPI_MASK = 0x7F
00075     };
00076 
00077     /** Create a BME280 instance
00078      *  which is connected to specified SPI pins
00079      *
00080      * @param mosi SPI MOSI pin
00081      * @param miso SPI MISO pin
00082      * @param sclk SPI SCLK pin
00083      * @param cs device CS pin
00084      */
00085     BME280_SPI(PinName mosi, PinName miso, PinName sclk, PinName cs);
00086 
00087     /** Destructor of BME280_SPI
00088      */
00089     virtual ~BME280_SPI();
00090 
00091     /** Initializa BME280 sensor
00092      *
00093      *  Configure sensor setting and read parameters for calibration
00094      *
00095      */
00096     void initialize(void);
00097 
00098     /** Read the current temperature value (degree Celsius) from BME280 sensor
00099      *
00100      * @return Temperature value (degree Celsius)
00101      */
00102     float getTemperature(void);
00103 
00104     /** Read the current pressure value (hectopascal) from BME280 sensor
00105      *
00106      * @return Pressure value (hectopascal)
00107      */
00108     float getPressure(void);
00109 
00110     /** Read the current humidity value (humidity %) from BME280 sensor
00111      *
00112      * @return Humidity value (humidity %)
00113      */
00114     float getHumidity(void);
00115 
00116 private:
00117 
00118     SPI         _spi;
00119     DigitalOut  _cs;
00120     uint16_t    dig_T1;
00121     int16_t     dig_T2, dig_T3;
00122     uint16_t    dig_P1;
00123     int16_t     dig_P2, dig_P3, dig_P4, dig_P5, dig_P6, dig_P7, dig_P8, dig_P9;
00124     uint16_t    dig_H1, dig_H3;
00125     int16_t     dig_H2, dig_H4, dig_H5, dig_H6;
00126     int32_t     t_fine;
00127 
00128 };
00129 
00130 #endif // MBED_BME280_SPI_H