AN3209 datasheet(9/42 Pages) STMICROELECTRONICS

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AN3209

Component overview

Doc ID 17419 Rev 2

9/42

2.1.2

M24LR64-R I2C interface

The M24LR64-R can work both in standard and Fast I2C modes. The device carries a built-

in 4-bit device type identifier code (1010b) compliant with the I2C bus definition. For the

demonstration application, the STM8L101K3 master operates at a speed of 100 kHz.

The M24LR64-R behaves as a slave for the I2C protocol with all memory operations

synchronized by the serial clock. The device I2C address is 1010 0000b (0xA0)

The I2C master writes and reads to/from the M24LR64-R memory. These basic operations

are performed by the M24LR64-R_Datalogger_application_firmware by calling i2c_ee.c

library functions.

Write operations

To write to the memory, the I2C master sends write commands to the M24LR64-R. The

command frame must be compliant with the format described in Figure 7.

The M24LR64-R_Datalogger_application_firmware calls the I2C_EE_PageWrite function

which programs a set of bytes into the EEPROM (see Table 2 for a description and an

example).

Figure 7.

Write I2C frame format

AC0, AC1

Antenna coils

I/O

VCC

Supply voltage

VSS

Ground

Table 1.

M24LR64-R signal names (continued)

Signal name

Function

Direction

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