Initialize the SPI to a basic functional state by following these steps:
- 1.Configure the
SS pin in the port peripheral.
- 2.Select the SPI host/client operation
by writing the Host/Client Select (MASTER) bit in the Control A (SPIn.CTRLA)
register.
- 3.In Host mode, select the clock speed
by writing the Prescaler (PRESC) bits and the Clock Double (CLK2X) bit in
SPIn.CTRLA.
- 4.Optional: Select the Data Transfer
mode by writing to the MODE bits in the Control B (SPIn.CTRLB) register.
- 5.Optional: Write the Data Order (DORD)
bit in SPIn.CTRLA.
- 6.Optional: Set up the Buffer mode by
writing the BUFEN and BUFWR bits in the Control B (SPIn.CTRLB) register.
- 7.Optional: To disable the multi-host
support in Host mode, write ‘
1
’ to the Client Select Disable (SSD)
bit in SPIn.CTRLB.
- 8.Enable the SPI by writing a
‘
1
’ to the ENABLE bit in SPIn.CTRLA.