SPRUII0F May 2019 – June 2024
For SPIBRR = 3 to 127:

For SPIBRR = 0, 1, or 2:

where:
LSPCLK = Low-speed peripheral clock frequency of the device
SPIBRR = Contents of the SPIBRR in the master SPI device
To determine what value to load into SPIBRR, you must know the device system clock (LSPCLK) frequency (that is device-specific) and the baud rate at which you are operating.