#include "bme680.h" #include "i2c.h" #include const double const_array1[16] = { 1, 1, 1, 1, 1, 0.99, 1, 0.992, 1, 1, 0.998, 0.995, 1, 0.99, 1, 1 }; const double const_array2[16] = { 8000000, 4000000, 2000000, 1000000, 499500.4995, 248262.1648, 125000, 63004.03226, 31281.28128, 15625, 7812.5, 3906.25, 1953.125, 976.5625, 488.28125, 244.140625 }; const int const_array1_int[16] = { 2147483647, 2147483647, 2147483647, 2147483647, 2147483647, 2126008810, 2147483647, 2130303777, 2147483647, 2147483647, 2143188679, 2136746228, 2147483647, 2126008810, 2147483647, 2147483647 }; const int const_array2_int[16] = { 4096000000, // too big ? 2048000000, 1024000000, 512000000, 255744255, 127110228, 64000000, 32258064, 16016016, 8000000, 4000000, 2000000, 1000000, 500000, 250000, 125000 }; double calc_temp_comp_1 ( uint32_t temp_adc , bme680_t *bme680) { double var1, var2, temp_comp; bme680_calibration *cal; cal = &bme680->cal; var1 = (((double)temp_adc / 16384.0) - ((double)cal->par_t1 / 1024.0)) * (double)cal->par_t2; var2 = ((((double)temp_adc / 131072.0) - ((double)cal->par_t1 / 8192.0)) * (((double)temp_adc / 131072.0) - ((double)cal->par_t1 / 8192.0))) * ((double)cal->par_t3 * 16.0); bme680->tfine_double = var1 + var2; temp_comp = (var1 + var2) / 5120.0; bme680->temp_comp_double = temp_comp; return temp_comp; } int calc_temp_comp_2 (uint32_t temp_adc, bme680_t *bme680) { int32_t var1, var2, var3, temp_comp; bme680_calibration *cal; cal = &bme680->cal; var1 = ((int32_t)temp_adc >> 3) - ((int32_t) cal->par_t1 << 1); var2 = (var1 * (int32_t)cal->par_t2) >> 11; var3 = ((((var1 >> 1) * (var1 >> 1)) >> 12) * ((int32_t)cal->par_t3 << 4)) >> 14; bme680->tfine_int = var2 + var3; temp_comp = (( (var2 + var3) * 5) + 128) >> 8; bme680->temp_comp_int = temp_comp; return temp_comp; } double calc_press_comp_1 ( uint32_t press_adc , bme680_t *bme680 ) { double var1, var2, var3, press_comp; bme680_calibration *cal; cal = &bme680->cal; var1 = ((double)bme680->tfine_double / 2.0) - 64000.0; var2 = var1 * var1 * ((double)cal->par_p6 / 131072.0); var2 = var2 + (var1 * (double)cal->par_p5 * 2.0); var2 = (var2 / 4.0) + ((double)cal->par_p4 * 65536.0); var1 = ((((double)cal->par_p3 * var1 * var1) / 16384.0) + ((double)cal->par_p2 * var1)) / 524288.0; var1 = (1.0 + (var1 / 32768.0)) * (double)cal->par_p1; press_comp = 1048576.0 - (double)press_adc; press_comp = ((press_comp - (var2 / 4096.0)) * 6250.0) / var1; var1 = ((double)cal->par_p9 * press_comp * press_comp) / 2147483648.0; var2 = press_comp * ((double)cal->par_p8 / 32768.0); var3 = (press_comp / 256.0) * (press_comp / 256.0) * (press_comp / 256.0) * (cal->par_p10 / 131072.0); press_comp = press_comp + (var1 + var2 + var3 + ((double)cal->par_p7 * 128.0)) / 16.0; bme680->press_comp_double = press_comp; return press_comp; } int calc_press_comp_2 ( uint32_t press_adc , bme680_t *bme680 ) { int32_t var1, var2, var3, press_comp; bme680_calibration *cal; cal = &bme680->cal; var1 = ((int32_t)bme680->tfine_int >> 1) - 64000; var2 = ((((var1 >> 2) * (var1 >> 2)) >> 11) * (int32_t)cal->par_p6) >> 2; var2 = var2 + ((var1 * (int32_t)cal->par_p5) << 1); var2 = (var2 >> 2) + ((int32_t)cal->par_p4 << 16); var1 = (((((var1 >> 2) * (var1 >> 2)) >> 13) * ((int32_t)cal->par_p3 << 5)) >> 3) + (((int32_t)cal->par_p2 * var1) >> 1); var1 = var1 >> 18; var1 = ((32768 + var1) * (int32_t)cal->par_p1) >> 15; press_comp = 1048576 - press_adc; // bosch code pg 19 says "press_raw" here ??? press_comp = (uint32_t)((press_comp - (var2 >> 12)) * ((uint32_t)3125)); if (press_comp >= (1 << 30)) press_comp = ((press_comp / (uint32_t)var1) << 1); else press_comp = ((press_comp << 1) / (uint32_t)var1); var1 = ((int32_t)cal->par_p9 * (int32_t)(((press_comp >> 3) * (press_comp >> 3)) >> 13)) >> 12; var2 = ((int32_t)(press_comp >> 2) * (int32_t)cal->par_p8) >> 13; var3 = ((int32_t)(press_comp >> 8) * (int32_t)(press_comp >> 8) * (int32_t)(press_comp >> 8) * (int32_t)cal->par_p10) >> 17; press_comp = (int32_t)(press_comp) + ((var1 + var2 + var3 + ((int32_t)cal->par_p7 << 7)) >> 4); bme680->press_comp_int = press_comp; return press_comp; } double calc_hum_comp_1 ( uint32_t hum_adc , bme680_t *bme680 ) { double var1, var2, var3, var4, hum_comp, temp_comp; bme680_calibration *cal; cal = &bme680->cal; temp_comp = bme680->temp_comp_double; var1 = hum_adc - (((double)cal->par_h1 * 16.0) + (((double)cal->par_h3 / 2.0) * temp_comp)); var2 = var1 * (((double)cal->par_h2 / 262144.0) * (1.0 + (((double)cal->par_h4 / 16384.0) * temp_comp) + (((double)cal->par_h5 / 1048576.0) * temp_comp * temp_comp))); var3 = (double)cal->par_h6 / 16384.0; var4 = (double)cal->par_h7 / 2097152.0; hum_comp = var2 + ((var3 + (var4 * temp_comp)) * var2 * var2); bme680->hum_comp_double = hum_comp; return hum_comp; } int calc_hum_comp_2 ( uint32_t hum_adc , bme680_t *bme680 ) { int32_t var1, var2, var3, var4, var5, var6, temp_scaled, hum_comp; bme680_calibration *cal; cal = &bme680->cal; temp_scaled = (int32_t)bme680->temp_comp_int; var1 = (int32_t)hum_adc - (int32_t)((int32_t)cal->par_h1 << 4) - (((temp_scaled * (int32_t)cal->par_h3) / ((int32_t)100)) >> 1); var2 = ((int32_t)cal->par_h2 * (((temp_scaled * (int32_t)cal->par_h4) / ((int32_t)100)) + (((temp_scaled * ((temp_scaled * (int32_t)cal->par_h5) / ((int32_t)100))) >> 6) / ((int32_t)100)) + ((int32_t)(1 << 14)))) >> 10; var3 = var1 * var2; var4 = (((int32_t)cal->par_h6 << 7) + ((temp_scaled * (int32_t)cal->par_h7) / ((int32_t)100))) >> 4; var5 = ((var3 >> 14) * (var3 >> 14)) >> 10; var6 = (var4 * var5) >> 1; hum_comp = (((var3 + var6) >> 10) * ((int32_t) 1000)) >> 12; bme680->hum_comp_int = hum_comp; return hum_comp; } int bme680_calibrate ( int fd , bme680_calibration *cal ) { uint8_t buffer[3] = {0, 0 ,0}; int err = 0; // start with temp params err |= i2c_read_reg(fd, 0xE9, 2, buffer); cal->par_t1 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x8A, 2, buffer); cal->par_t2 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x8C, 1, buffer); cal->par_t3 = buffer[0]; // pressure err |= i2c_read_reg(fd, 0x8E, 2, buffer); cal->par_p1 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x90, 2 , buffer); cal->par_p2 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x92, 1, buffer); cal->par_p3 = buffer[0]; err |= i2c_read_reg(fd, 0x94, 2, buffer); cal->par_p4 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x96, 2, buffer); cal->par_p5 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x99, 1, buffer); cal->par_p6 = buffer[0]; err |= i2c_read_reg(fd, 0x98, 1, buffer); // strange order cal->par_p7 = buffer[0]; err |= i2c_read_reg(fd, 0x9C, 2, buffer); cal->par_p8 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0x9E, 2, buffer); cal->par_p9 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0xA0, 1, buffer); cal->par_p10 = buffer[0]; // humidity err |= i2c_read_reg(fd, 0xE2, 2, buffer); cal->par_h1 = (buffer[1] << 4) | (buffer[0] & 0xF); err |= i2c_read_reg(fd, 0xE1, 2, buffer); cal->par_h2 = (buffer[0] << 4) | ((buffer[1] >> 4) & 0xF); err |= i2c_read_reg(fd, 0xE4, 1, buffer); cal->par_h3 = buffer[0]; err |= i2c_read_reg(fd, 0xE5, 1, buffer); cal->par_h4 = buffer[0]; err |= i2c_read_reg(fd, 0xE6, 1, buffer); cal->par_h5 = buffer[0]; err |= i2c_read_reg(fd, 0xE7, 1, buffer); cal->par_h6 = buffer[0]; err |= i2c_read_reg(fd, 0xE8, 1, buffer); cal->par_h7 = buffer[0]; // gas err |= i2c_read_reg(fd, 0xED, 1, buffer); cal->par_g1 = buffer[0]; err |= i2c_read_reg(fd, 0xEB, 2, buffer); cal->par_g2 = (buffer[1] << 8) | buffer[0]; err |= i2c_read_reg(fd, 0xEE, 1, buffer); cal->par_g2 = buffer[0]; // todo more return err; } void print_calibration ( bme680_calibration *cal ) { printf("par_t1: %d\n", cal->par_t1); printf("par_t2: %d\n", cal->par_t2); printf("par_t3: %d\n", cal->par_t3); printf("par_p1: %d\n", cal->par_p1); printf("par_p2: %d\n", cal->par_p2); printf("par_p3: %d\n", cal->par_p3); printf("par_p4: %d\n", cal->par_p4); printf("par_p5: %d\n", cal->par_p5); printf("par_p6: %d\n", cal->par_p6); printf("par_p7: %d\n", cal->par_p7); printf("par_p8: %d\n", cal->par_p8); printf("par_p9: %d\n", cal->par_p9); printf("par_p10: %d\n", cal->par_p10); printf("par_h1: %d\n", cal->par_h1); printf("par_h2: %d\n", cal->par_h2); printf("par_h3: %d\n", cal->par_h3); printf("par_h4: %d\n", cal->par_h4); printf("par_h5: %d\n", cal->par_h5); printf("par_h6: %d\n", cal->par_h6); printf("par_h7: %d\n", cal->par_h7); }