mini glider FSG
Fork of MS5837 by
MS5837.cpp
- Committer:
- CodyMarquardt
- Date:
- 2018-08-13
- Revision:
- 1:a8eea2a2263f
- Parent:
- 0:5f6034409fd0
File content as of revision 1:a8eea2a2263f:
#include <stdlib.h> #include "MS5837.h" /* * Sensor operating function according data sheet */ void MS5837::MS5837Init(void) { MS5837Reset(); MS5837ReadProm(); return; } /* Send soft reset to the sensor */ void MS5837::MS5837Reset(void) { /* transmit out 1 byte reset command */ ms5837_tx_data[0] = ms5837_reset; if ( i2c.write( device_address, ms5837_tx_data, 1 ) ); //printf("send soft reset\n\r"); wait_ms(20); } /* read the sensor calibration data from rom */ void MS5837::MS5837ReadProm(void) { uint8_t i,j; for (i=0; i<8; i++) { j = i; ms5837_tx_data[0] = ms5837_PROMread + (j<<1); if ( i2c.write( device_address, ms5837_tx_data, 1 ) ); if ( i2c.read( device_address, ms5837_rx_data, 2 ) ); C[i] = ms5837_rx_data[1] + (ms5837_rx_data[0]<<8); } } /* Start the sensor pressure conversion */ void MS5837::MS5837ConvertD1(void) { ms5837_tx_data[0] = ms5837_convD1; if ( i2c.write( device_address, ms5837_tx_data, 1 ) ); } /* Start the sensor temperature conversion */ void MS5837:: MS5837ConvertD2(void) { ms5837_tx_data[0] = ms5837_convD2; if ( i2c.write( device_address, ms5837_tx_data, 1 ) ); } /* Read the previous started conversion results */ int32_t MS5837::MS5837ReadADC(void) { int32_t adc; wait_ms(150); ms5837_tx_data[0] = ms5837_ADCread; if ( i2c.write( device_address, ms5837_tx_data, 1 ) ); if ( i2c.read( device_address, ms5837_rx_data, 3 ) ); adc = ms5837_rx_data[2] + (ms5837_rx_data[1]<<8) + (ms5837_rx_data[0]<<16); //printf("ADC value: %x\n", adc); return (adc); } /* return the results */ float MS5837::MS5837_Pressure (void) { return P_MS5837; } float MS5837::MS5837_Temperature (void) { return T_MS5837; } /* Sensor reading and calculation procedure */ void MS5837::Barometer_MS5837(void) { int32_t dT, temp; int64_t OFF, SENS, press; //no need to do this everytime! MS5837ConvertD1(); // start pressure conversion D1 = MS5837ReadADC(); // read the pressure value MS5837ConvertD2(); // start temperature conversion D2 = MS5837ReadADC(); // read the temperature value //printf("D1 = %d\n", D1); /* calculation according MS5837-01BA data sheet DA5837-01BA_006 */ dT = D2 - (C[5]* 256); OFF = (int64_t)C[2] * (1<<16) + ((int64_t)dT * (int64_t)C[4]) / (1<<7); SENS = (int64_t)C[1] * (1<<15) + ((int64_t)dT * (int64_t)C[3]) / (1<<8); temp = 2000 + (dT * C[6]) / (1<<23); T_MS5837 = (float) temp / 100.0f; // result of temperature in deg C in this var press = (((int64_t)D1 * SENS) / (1<<21) - OFF) / (1<<13); P_MS5837 = (float) press / 10.0f; // result of pressure in mBar in this var if (P_MS5837 < 900 || P_MS5837 > 3000) { MS5837Reset(); // reset the sensor MS5837ReadProm(); // read the calibration values } } float MS5837::get_depth_initial(void){ depth_iter = 0; Depth_0 = 0; for(int i = 0; i < 5; i++){ Barometer_MS5837(); depth_iter = ((P_MS5837)*1.019716); Depth_0 = depth_iter + Depth_0; } Depth_0 = Depth_0/5; if(Depth_0 < 1000 || Depth_0 > 1100){ MS5837Init(); get_depth_initial(); } return Depth_0; } float MS5837::get_depth(void) { depth_iter = 0; depth = 0; for(int i = 0; i <= 2; i++){ Barometer_MS5837(); depth_iter = ((P_MS5837)*1.019716)-Depth_0; depth = depth_iter + depth; } depth = depth/3; return depth; }