SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
In the 7-bit addressing format (Figure 13-11), the first byte after the START condition consists of a 7-bit peripheral address followed by the R/ W bit (in the LSB). The R/ W bit determines the direction of the data transfer:
An extra clock cycle dedicated for acknowledgment (ACK) is inserted after each byte. If the ACK is inserted by the peripheral after the first byte from the controller, it is followed by n bits of data from the transmitter (controller or peripheral, depending on the R/ W bit). The device I2C allows n to be a number between 2 to 8, programmable by the bit count (BC) field of ICMDR. After the data bits have been transferred, the receiver inserts an ACK bit.
To select the 7-bit addressing format, write 0 to the expanded address enable (XA) bit of I2CMDR and make sure the free data format mode is off (FDF = 0 in ICMDR).