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Version 3.3 – November 2024

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3.2 I2C sequences

The commands are 16-bit. Data is read from the sensor in multiples of 16-bit words, each followed by an 8-

bit checksum to ensure communication reliability. I2C sequences can be aborted with a NACK and STOP

condition.

I2C master writes 16 bit command

I2C master writes 16 bit command with a 16bit argument and CRC byte

The CRC byte must be generated from the 16-bit argument. See section 3.4 for details.

When the sensor responds with a NACK on to the CRC byte, a new START condition and valid command

is required to further communicate with the sensor.

Alternatively, with CRC disabled, the I2C master writes a 16bit command with a 16bit argument

I2C master sends read header and receives multiple 16bit words with CRC byte

Alternatively, with the CRC disabled, I2C master sends read header and receives multiple 16bit words

Dark areas with white text indicate that the sensor controls the SDA (Data) line.

or

or

≈

S

W

I2CAdr[6:0

]

Cmd[15:8]

Cmd[7:0]

CRC[7:0]

Arg[15:8]

Arg[7:0]

S

W

I2CAdr[6:0

]

Cmd[15:8]

Cmd[7:0]

Arg[15:8]

Arg[7:0]

S

W

I2CAdr[6:0

]

Cmd[15:8]

Cmd[7:0]

S

R

I2CAdr[6:0

]

Data1[15:8]

Data1[7:0]

CRC1[7:0]

P

Data2[15:8]

Data2[7:0]

CRC2[7:0]

P

DataX[15:8]

DataX[7:0]

CRCX[7:0]

P

or

S

R

I2CAdr[6:0

]

Data1[15:8]

Data1[7:0]

P

Data2[15:8]

Data2[7:0]

P

DataX[15:8]

DataX[7:0]

P

or

≈