LSM9DS1 Datasheet, PDF (33/72 Pages) –

LSM9DS1
Digital interfaces
5.2.2
5.2.3
SPI write
Figure 19. Accelerometer and gyroscope SPI write protocol
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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.
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Figure 20. Multiple byte SPI write protocol (2-byte example)
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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
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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.
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