LSM303DLM datasheet(17/38 Pages) STMICROELECTRONICS

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LSM303DLM

Digital interfaces

Doc ID 018725 Rev 1

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Digital interfaces

The registers embedded inside the LSM303DLM are accessible through two separate I2C

serial interfaces; one for the accelerometer core and the other for the magnetometer core.

The two interfaces can be connected together on the PCB.

7.1

I2C serial interface

The LSM303DLM I2C is a bus slave. The I2C is employed to write the data into the registers

whose content can also be read back.

The relevant I2C terminology is given in the table below.

There are two signals associated with the I2C bus; the serial clock line (SCL) and the serial

data line (SDA). The latter is a bidirectional line used for sending and receiving the data

to/from the interface.

Table 7.

Serial interface pin description

Pin name

Pin description

SCL_A

I2C serial clock (SCL) for accelerometer

SDA_A

I2C serial data (SDA) for accelerometer

SCL_M

I2C serial clock (SCL) for magnetometer

SDA_M

I2C serial data (SDA) for magnetometer

Table 8.

Serial interface pin description

Term

Description

Transmitter

The device which sends data to the bus

Receiver

The device which receives data from the bus

Master

The device which initiates a transfer, generates clock signals, and terminates a

transfer

Slave

The device addressed by the master

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