LSM9DS1TR datasheet(33/72 Pages) STMICROELECTRONICS

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LSM9DS1

Digital interfaces

5.2.2

SPI write

Figure 19. Accelerometer and gyroscope SPI write protocol

The SPI write command is performed with 16 clock pulses. A multiple byte write command

is performed by adding blocks of 8 clock pulses to the previous one.

bit 0: WRITE bit. The value is 0.

bit 1 -7: address AD(6:0). This is the address field of the indexed register.

bit 8-15: data DI(7:0) (write mode). This is the data that is written inside the device (MSb

first).

bit 16-... : data DI(...-8). Further data in multiple byte writes.

Figure 20. Multiple byte SPI write protocol (2-byte example)

5.2.3

SPI read in 3-wire mode

3-wire mode is entered by setting the CTRL_REG8 (22h)(SIM) bit equal to ‘1’ (SPI serial

interface mode selection).

Figure 21. Accelerometer and gyroscope SPI read protocol in 3-wire mode

The SPI read command is performed with 16 clock pulses:

bit 0: READ bit. The value is 1.

bit 1-7: address AD(6:0). This is the address field of the indexed register.

bit 8-15: data DO(7:0) (read mode). This is the data that is read from the device (MSb first).

A multiple read command is also available in 3-wire mode.

LSM9DS1TR Datasheet(PDF) 33 Page - STMicroelectronics