BMP384 pressur compensation

[simon8]

Hi all,

I'm working with an BMP384 but I have question about temp/press compensation. In the datasheet at page  55 I have this

To parse calib data I have this function

static void parse_calib_data(const uint8_t *reg_data, struct bmp3_dev *dev)

{

/* Temporary variable to store the aligned trim data */

struct bmp3_reg_calib_data *reg_calib_data = &dev->calib_data.reg_calib_data;

reg_calib_data->par_t1 = BMP3_CONCAT_BYTES(reg_data[1], reg_data[0]);

reg_calib_data->par_t2 = BMP3_CONCAT_BYTES(reg_data[3], reg_data[2]);

reg_calib_data->par_t3 = (int8_t)reg_data[4];

reg_calib_data->par_p1 = (int16_t)BMP3_CONCAT_BYTES(reg_data[6], reg_data[5]);

reg_calib_data->par_p2 = (int16_t)BMP3_CONCAT_BYTES(reg_data[8], reg_data[7]);

reg_calib_data->par_p3 = (int8_t)reg_data[9];

reg_calib_data->par_p4 = (int8_t)reg_data[10];

reg_calib_data->par_p5 = BMP3_CONCAT_BYTES(reg_data[12], reg_data[11]);

reg_calib_data->par_p6 = BMP3_CONCAT_BYTES(reg_data[14], reg_data[13]);

reg_calib_data->par_p7 = (int8_t)reg_data[15];

reg_calib_data->par_p8 = (int8_t)reg_data[16];

reg_calib_data->par_p9 = (int16_t)BMP3_CONCAT_BYTES(reg_data[18], reg_data[17]);

reg_calib_data->par_p10 = (int8_t)reg_data[19];

reg_calib_data->par_p11 = (int8_t)reg_data[20];

}

So if I understand well the par_t1 is not good in my function I should do for par_t1

BMP3_CONCAT_BYTES(reg_data[1], reg_data[0]) / 0.00390625

Am I right?

Thanks

[BSTRobin]

Hi simon8 ,

par_t1 is 16 bit variable, BMP3_CONCAT_BYTES merge two reg_data[1], reg_data[0] 8 bit variable to par_t1 16 bit variable.
#define BMP3_CONCAT_BYTES(msb, lsb) (((uint16_t)msb << 😎 | (uint16_t)lsb)

[simon8]

Ah nice right now I have this definition 😁

#define BMP3_CONCAT_BYTES(msb, lsb) (((uint16_t)msb << 8) | (uint16_t)lsb)

[BSTRobin]

Yes, correct.