Datasheet

Writing '0' to this bit has no effect.

Bit 0 – MB Master on Bus

This flag is set when a byte is transmitted in master 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 master 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 master forces the SCL line low, stretching the I

C 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.

SAM D21 Family

SERCOM I2C – Inter-Integrated Circuit

Datasheet Complete

DS40001882D-page 613