ZHCSRH9E April 2009 – January 2023 TCA6408A
PRODUCTION DATA
To write on the I2C bus, the controller will send a START condition on the bus with the address of the target, as well as the last bit (the R/ W bit) set to 0, which signifies a write. After the target sends the acknowledge bit, the controller will then send the register address of the register to which it wishes to write. The target will acknowledge again, letting the controller know it is ready. After this, the controller will start sending the register data to the target until the controller has sent all the data necessary (which is sometimes only a single byte), and the controller will terminate the transmission with a STOP condition.
#SCPS133IMG5008 shows an example of writing a single byte to a target register.