8.5.1.5 Addressing Transfer Formats

Each device on the bus has a unique slave address. The LP8556 operates as a slave device with 7-bit address combined with data direction bit. Slave address is 2Ch as 7-bit or 58h for write and 59h for read in 8-bit format.

Before any data is transmitted, the master transmits the slave I.D. The slave device should send an acknowledge signal on the SDA line, once it recognizes its address.

The slave address is the first seven bits after a Start Condition. The direction of the data transfer (R/W) depends on the bit sent after the slave address — the 8th bit.

When the slave address is sent, each device in the system compares this slave address with its own. If there is a match, the device considers itself addressed and sends an acknowledge signal. Depending upon the state of the R/W bit (1:read, 0:write), the device acts as a transmitter or a receiver.

Figure 16. I²C Chip Address (0x2C)