HP20x_dev.cpp

00001 /*
00002  * File name  : HP20x_dev.cpp
00003  * Description: Driver for I2C PRECISION BAROMETER AND ALTIMETER [HP206C]
00004  * Author     : Oliver Wang from Seeed studio
00005  * Version    : V0.1
00006  * Create Time: 2014/04
00007  * Change Log :
00008 */
00009 
00010 /****************************************************************************/
00011 /***        Include files                                                 ***/
00012 /****************************************************************************/
00013 #include "HP20x_dev.h"
00014 #include "mbed.h"
00015 //#include "KalmanFilter.h"
00016 /****************************************************************************/
00017 /***       Local Variable                                                 ***/
00018 /****************************************************************************/
00019 
00020 
00021 
00022 /****************************************************************************/
00023 /***       Class member Functions                                         ***/
00024 /****************************************************************************/
00025 /*
00026  **@ Function name: HP20x_dev
00027  **@ Description: Constructor
00028  **@ Input: none
00029  **@ OutPut: none
00030  **@ Retval: none
00031 */
00032 
00033 HP20x_dev::HP20x_dev(PinName p_sda, PinName p_scl) : i2c(p_sda, p_scl) {
00034    OSR_CFG = HP20X_CONVERT_OSR1024;
00035    OSR_ConvertTime = 25; 
00036 }
00037 
00038 
00039 /*
00040  **@ Function name: begin
00041  **@ Description: Initialize HP20x_dev
00042  **@ Input: none
00043  **@ OutPut: none
00044  **@ Retval: none
00045 */
00046 void HP20x_dev::reset()
00047 {
00048  
00049   /* Reset HP20x_dev */
00050   char data_write[1];
00051   data_write[0] = HP20X_SOFT_RST;
00052   if ( i2c.write( HP20X_ADDRESS,  data_write, 1,0 ) );
00053    wait_ms(60);
00054 
00055 }
00056 
00057 /*
00058  **@ Function name: isAvailable
00059  **@ Description: Indicate whether it's available
00060  **@ Input: none
00061  **@ OutPut: none
00062  **@ Retval: uchar 
00063 */
00064 char HP20x_dev::isAvailable()
00065 {
00066   char ret = readByte(HP20X_ADDRESS,REG_PARA|HP20X_RD_REG_MODE);//readreg
00067   return ret;
00068 }
00069 
00070 
00071 
00072 long HP20x_dev::ReadPressure(void)
00073 {
00074  
00075   
00076   writeByte(HP20X_ADDRESS,HP20X_WR_CONVERT_CMD,OSR_CFG);
00077    
00078 wait_ms(OSR_ConvertTime);
00079 
00080     char data_write[1];
00081     data_write[0] =  HP20X_READ_P;
00082   if ( i2c.write( HP20X_ADDRESS,data_write,1,0 ) );
00083  
00084     long TempData = 0;
00085     long tmpArray[3]={0};
00086     
00087     
00088     /* Require three bytes from slave */
00089    
00090     char data[3];
00091    
00092     data_write[0] = I2C_DID_RD_MASK;
00093     i2c.write(HP20X_ADDRESS, data_write, 1, 1); // no stop
00094     i2c.read(HP20X_ADDRESS, data, 3, 0); 
00095     for(int ii = 0; ii < 3; ii++) {
00096      tmpArray[ii] = data[ii];}
00097     
00098     /* MSB */
00099     TempData = tmpArray[0]<<16 | tmpArray[1]<<8 | tmpArray[2];
00100 
00101     
00102     if(TempData&0x800000)
00103     {
00104         TempData|=0xff000000;
00105     }
00106 
00107     return TempData;        
00108    
00109 } 
00110 
00111 
00112 void HP20x_dev::writeByte(uint8_t address, uint8_t subAddress, uint8_t data)
00113     {
00114        char data_write[2];
00115        data_write[0] = subAddress;
00116        data_write[1] = data;
00117        i2c.write(address, data_write, 2, 0);
00118     }
00119 
00120 char HP20x_dev::readByte(uint8_t address, uint8_t subAddress)
00121     {
00122         char data[1]; // `data` will store the register data     
00123         char data_write[1];
00124         data_write[0] = subAddress;
00125         i2c.write(address, data_write, 1, 1); // no stop
00126         i2c.read(address, data, 1, 0); 
00127         return data[0]; 
00128     }
00129 
00130 
00131 
00132 /**************************************END OF FILE**************************************/