26.10.7 Interrupt Flag Status and Clear

The Client on Bus flag (SB) is set when a byte is successfully received in Host read mode, i.e., no arbitration lost or bus error occurred during the operation. When this flag is set, the Host forces the SCL line low, stretching the I²C clock period. The SCL line will be released and SB will be cleared on one of the following actions:

• Writing to ADDR.ADDR
• Writing to DATA.DATA
• Reading DATA.DATA when smart mode is enabled (CTRLB.SMEN)
• Writing a valid command to CTRLB.CMD

Writing '1' to this bit location will clear the SB flag. The transaction will not continue or be terminated until one of the above actions is performed.

Writing '0' to this bit has no effect.

This flag is set when a byte is transmitted in Host write mode. The flag is set regardless of the occurrence of a bus error or an arbitration lost condition. MB is also set when arbitration is lost during sending of NACK in Host read mode, or when issuing a start condition if the bus state is unknown. When this flag is set and arbitration is not lost, the Host forces the SCL line low, stretching the I²C clock period. The SCL line will be released and MB will be cleared on one of the following actions:

• Writing to ADDR.ADDR
• Writing to DATA.DATA
• Reading DATA.DATA when smart mode is enabled (CTRLB.SMEN)
• Writing a valid command to CTRLB.CMD

Writing '1' to this bit location will clear the MB flag. The transaction will not continue or be terminated until one of the above actions is performed.

Writing '0' to this bit has no effect.