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5. Digital Interface Description

The SDP3x-digital interface is compatible with the I2C protocol. This chapter describes the command set for SDP3x-digital.

For detailed information about the I2C protocol, please check the document "NXP I2C-bus specification and user manual".

5.1

I2C Address

The I2C address for SDP3x-digital can be selected with the ADDR pin. For more information refer to section 3.3.

5.2

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 master writes 16 bit command

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

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

I2C sequences can be aborted with a NACK and STOP condition.

5.3

I2C Commands

The command set of the SDP3x-digital consists of a set of different commands:

-

Continuous measurement

o

Start Continuous measurement commands

o

Stop measurement command

-

Triggered measurement commands

-

Read product identifier and serial number

-

Soft reset

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

or

DataX[15:8]

DataX[7:0]

CRCX[7:0]

P

or

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