Typical Transmit Sequence

1.The Host generates a Start condition by setting the SEN bit.
2.SSPxIF is set by hardware on completion of the Start.
3.SSPxIF is cleared by software.
4.The MSSP module will wait the required start time before any other operation takes place.
5.Software loads the SSPxBUF with the client address and the R/W bit. In Host Transmit mode, the R/W value is zero.
6.Address is shifted out the SDA pin until all eight bits are transmitted. Transmission begins as soon as SSPxBUF is written to.
7.The MSSP module shifts in the ACK value from the client device and writes its into the ACKSTAT bit.
8.The MSSP module generates an interrupt at the end of the ninth clock cycle by setting the SSPxIF bit.
9.Software loads the SSPxBUF with eight bits of data.
10.Data is shifted out the SDA pin until all eight bits are transmitted.
11.The MSSP module shifts in the ACK bit from the client device and writes its value into the ACKSTAT bit.
12.Steps 8-11 are repeated for all transmitted data bytes.
13.The user generates a Stop or Restart condition by setting the PEN or RSEN bits, respectively. An Interrupt is generated once the Stop/Restart condition is complete.

Figure 1. I²C Host Mode Waveform (Transmission, 7-Bit Address)

Figure 2. I²C Host Mode Waveform (Transmission, 10-Bit Address)