Data Sheet

Bosch Sensortec | BME280 Data sheet
24 | 55
Modifications reserved | Data subject to change without notice
Document number: BST-BME280-DS002-15
Revision_1.6_092018
Table 15: Computational requirements for compensation formulas
Compensation of
Number of clocks (ARM Cortex-M3)
32 bit integer
64 bit integer
Double precision
Humidity
~83
–
~2900
11
Temperature
~46
–
~2400
11
Pressure
~112
12
~1400
~5400
11
4.2.2 Trimming parameter readout
The trimming parameters are programmed into the devices’ non-volatile memory (NVM) during
production and cannot be altered by the customer. Each compensation word is a 16-bit signed or
unsigned integer value stored in two’s complement. As the memory is organized into 8-bit words, two
words must always be combined in order to represent the compensation word. The 8-bit registers are
named calib00…calib41 and are stored at memory addresses 0x88…0xA1 and 0xE1…0xE7. The
corresponding compensation words are named dig_T# for temperature compensation related values,
dig_P# for pressure related values and dig_H# for humidity related values. The mapping is seen in
Table 16.
Table 16: Compensation parameter storage, naming and data type
Register Address
Register content
Data type
0x88 / 0x89
dig_T1 [7:0] / [15:8]
unsigned short
0x8A / 0x8B
dig_T2 [7:0] / [15:8]
signed short
0x8C / 0x8D
dig_T3 [7:0] / [15:8]
signed short
0x8E / 0x8F
dig_P1 [7:0] / [15:8]
unsigned short
0x90 / 0x91
dig_P2 [7:0] / [15:8]
signed short
0x92 / 0x93
dig_P3 [7:0] / [15:8]
signed short
0x94 / 0x95
dig_P4 [7:0] / [15:8]
signed short
0x96 / 0x97
dig_P5 [7:0] / [15:8]
signed short
0x98 / 0x99
dig_P6 [7:0] / [15:8]
signed short
0x9A / 0x9B
dig_P7 [7:0] / [15:8]
signed short
0x9C / 0x9D
dig_P8 [7:0] / [15:8]
signed short
0x9E / 0x9F
dig_P9 [7:0] / [15:8]
signed short
0xA1
dig_H1 [7:0]
unsigned char
0xE1 / 0xE2
dig_H2 [7:0] / [15:8]
signed short
0xE3
dig_H3 [7:0]
unsigned char
0xE4 / 0xE5[3:0]
dig_H4 [11:4] / [3:0]
signed short
0xE5[7:4] / 0xE6
dig_H5 [3:0] / [11:4]
signed short
11
Use only recommended for high-level programming languages like Matlab™ or LabVIEW™
12
Use only recommended for 8-bit micro controllers