SLVUC05A November 2020 – July 2022 TPS25750
The PD Controller provides one I2C slave. The I2Cs slave is meant to be connected to an Embedded Controller (EC).
The Host Interface defines how the registers are accessed from I2C slave port ands and all slave addresses. Slave Address #1 is selected by the customer using the ADCIN1 and ADCIN2 pins on the PD controller. See also Table 4-1 for more details about the slave addresses.
The Host Interface provides general status information to the master of these I2C interfaces about the PD Controller, ability to control the PD Controller, status of USB Type-C Port and communications to/from a connected device (Port Partner) and/or cable plug via USB PD messages. All Host Interface communication that uses the Unique I2C address is referred to as Unique Address Interface.
The PD Controller supports a register-based Unique Address Interface. Section 1.3.2 lists the Unique Address Interface registers and Chapter 2 provides detailed Unique Address Interface register descriptions.
The key to the protocol diagrams is in the SMBus Specification, version 2.0 and is repeated here in part in Figure 1-1.