I3C single data rate write flow control

An apparatus adapted to operate as a master device when coupled to a serial bus, the apparatus comprising:

• a bus interface circuit configured to couple the apparatus to the serial bus;
• and
• a processing device configured to:
• initiate a write transaction between the apparatus and a slave device, wherein the write transaction includes a plurality of data frames to be transmitted over a data line of the serial bus;
• transmit a transition bit from the apparatus in place of a parity bit of a first data frame while transmitting the first data frame to the slave device;
• and
• terminate the write transaction when the slave device is determined to be driving the data line of the serial bus while the transition bit is being transmitted from the apparatus over the data line of the serial bus.

A method performed at a slave device coupled to a serial bus, comprising:

• receiving a configuration command from a master device indicating that data frames transmitted during a write transaction include transition bits in place of parity bits;
• receiving a first data frame from a data line of the serial bus during the write transaction;
• and
• driving the data line to assert a flow control request while receiving a first transition bit of the first data frame from the data line.

An apparatus adapted to operate as a slave device when coupled to a serial bus, the apparatus comprising:

• a bus interface circuit configured to couple the apparatus to the serial bus;
• and
• a processing device configured to:
• receive a configuration command from a master device indicating that data frames transmitted during a write transaction include transition bits in place of parity bits;
• receive a first data frame from a data line of the serial bus during the write transaction;
• and
• cause the bus interface circuit to assert a flow control request by driving the data line while a first transition bit of the first data frame is being received from the data line.