Hi, I'm using the BME280 for a project, and is having hard time converting the sensor's ADC temperature value into "human" readable temperature, the values always off. I'm not sure whether the issue is with the compensation equations or somewhere else. I'm able to write and read data back and forth between the BME280 sensor and the microcontroller. Below are sample pictures of the I2C communication Get Version Raw Temp and Pressure Read Calibration Values Compensation Equations to convert raw ADC value into human readable temperature. For instance, the UT value at this moment in time is 0x00086b2b. After that value went throught the equations, the t_fine_temp value is 0x00000594 or 1428 in decimal which is 14.28 degree C which i think is incorrect. Unfortunately, i don't know what the correct value should be. int32_t BME280_CalcT(int32_t UT)
{
#if 1
volatile sLWord t_fine_temp = 0x0000;
volatile sLWord t_fine_temp2= 0x0000;
//int32_t t_fine_temp3;
//int32_t t_fine_1;
#if 1
t_fine_temp = ((((UT >> 3) - ((sLWord)cal_param.dig_T1 << 1))) * ((sLWord)cal_param.dig_T2)) >> 11;
t_fine_temp2 = (((((UT >> 4) - ((sLWord)cal_param.dig_T1)) * ((UT >> 4) - ((sLWord)cal_param.dig_T1))) >> 12) * ((sLWord)cal_param.dig_T3)) >> 14;
t_fine_temp += t_fine_temp2;
t_fine_temp = ((t_fine_temp * 5) + 128) >> 8;
#endif
return t_fine_temp;
#endif
} cal_param 0x00000116 0x000116`Ram
dig_T1 0x596f 0x000116`Ram
dig_T2 0x1067 0x000118`Ram
dig_T3 0x3200 0x00011a`Ram Can anyone show me where thing went wrong ? Thank you very much Vu
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