STA321MPL1 datasheet(18/80 Pages) STMICROELECTRONICS

18 / 80 page

I2C bus operation

STA321MPL1

18/80

DocID029389 Rev 1

The 8th bit (LSB) identifies a read or write operation RW. This bit is set to 1 in read mode

and 0 for write mode. After a START condition, the STA321MPL1 identifies the device

address on the bus and if a match is found, it acknowledges the identification on the SDA

bus during the 9th-bit time. The byte following the device identification byte is the internal

space address.

4.3

Write operation

Following a START condition, the master sends a device select code with the RW bit set

to 0. The STA321MPL1 acknowledges this and the writes for the byte of the internal

address.

After receiving the internal byte address, the STA321MPL1 responds again with an

acknowledgement.

4.3.1

Byte write

In byte write mode, the master sends one data byte, this is acknowledged by the Omega

FFX core. The master then terminates the transfer by generating a STOP condition.

4.3.2

Multi-byte write

The multi-byte write modes can start from any internal address. The master generating a

STOP condition terminates the transfer.

Figure 6. Write mode sequence

STA321MPL1 数据表(PDF) 18 Page - STMicroelectronics