USART in Host SPI Mode vs. SPI

The USART in Host SPI mode is fully compatible with a stand-alone SPI peripheral. Their data frame and timing configurations are identical. Some SPI specific special features are, however, not supported with the USART in Host SPI mode:
  • Write Collision Flag Protection
  • Double-Speed mode
  • Multi-Host support

A comparison of the pins used with USART in Host SPI mode and with SPI is shown in the table below.

Table 25-3. Comparison of USART in Host SPI Mode and SPI Pins
USARTSPIComment
TXDMOSIHost out
RXDMISOHost in
XCKSCKFunctionally identical
-SSNot supported by USART in Host SPI mode(1)
Note:
  1. For the stand-alone SPI peripheral, this pin is used with the Multi-Host function or as a dedicated Client Select pin. The Multi-Host function is not available with the USART in Host SPI mode, and no dedicated Client Select pin is available.