Using TMR2 as Alternate SPI Clock

The Timer 2 peripheral can be used as an alternative clock for the MSSP peripheral and can be used in the SPI clock configuration.

For example, to create a 10 kHz SPI clock, modify the Timer Period to 50 µs. This corresponds to 20 kHz since the SPI uses TMR2output/2 as clock, meaning that 20 kHz / 2 = 10 kHz frequency.

The following code examples will present how to set up the TMR2 peripheral and be used as clock source for the SPI configured as Master communicating to two Slave devices, alternatively.

To achieve the functionality described by the use case, the following actions will have to be performed:

System clock initialization
TMR2 initialization
SPI1 initialization
PPS initialization
Port initialization
Slave control functions
Data exchange function