PIC18LF24K Datasheet, PDF (375/594 Pages) –

FIGURE 26-28: I²C MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS)
SDA
SCL
SSPxIF
Write SSPxCON2<0> SEN = 1
Start condition begins
SEN = 0
Transmit Address to Slave
R/W = 0
A7 A6 A5 A4 A3 A2 A1
ACK = 0
From slave, clear ACKSTAT bit SSPxCON2<6>
ACKSTAT in
SSPxCON2 = 1
Transmitting Data or Second Half
of 10-bit Address
ACK
D7 D6 D5 D4 D3 D2 D1 D0
SSPxBUF written with 7-bit address and R/W
start transmit
S
1 23456789
1 2 34 56 789
P
SCL held low
while CPU
responds to SSPxIF
Cleared by software
Cleared by software service routine
from SSP interrupt
Cleared by software
BF (SSPxSTAT<0>)
SEN
SSPxBUF written
After Start condition, SEN cleared by hardware
SSPxBUF is written by software
PEN
R/W