37.4.1 I2C Client Mode Operation

The I2C module provides four Client Operation modes as selected by the I2C Mode Select (MODE) bits:
  • I2C Client mode with recognition of up to four 7-bit addresses
  • I2C Client mode with recognition of up to two masked 7-bit addresses
  • I2C Client mode with recognition of up to two 10-bit addresses
  • I2C Client mode with recognition of one masked 10-bit address

During operation, the client device waits until module hardware detects a Start condition on the bus. Once the Start condition is detected, the client waits for the incoming address information to be received by the receive shift register. The address is then compared to the addresses stored in the I2C Address 0/1/2/3 registers (I2CxADR0, I2CxADR1, I2CxADR2, I2CxADR3), and if an address match is detected, client hardware transfers the matching address into either the I2CxADB0/I2CxADB1 registers or the I2CxRXB register, depending on the state of the Address Buffer Disable (ABD) bit. If there are no address matches, there is no response from the client.