20.2.2 Message Protocol

A typical I²C message is illustrated in Figure 20-3. In this example, the message will read a specified byte from a 24LC256 I²C serial EEPROM. The I²C device will act as the host and the 24LC256 device will act as the client.

Figure 20-3 illustrates the data as driven by the host device and the client device, taking into account that the combined SDAx line is a wired-AND of the host and client data. The host device controls and sequences the protocol. The client device will only drive the bus at specifically determined times.

Figure 20-3. A Typical I²C Message: Read of Serial EEPROM (Random Address Mode)