21.2.2 Framed Mode SPI Operation

In Framed mode operation, the frame host controls the generation of the frame synchronization pulse. The SPI clock is still generated by the SPI host and is continuously running. Figure 21-4 and Figure 21-5 illustrate SPI frame host and frame client device connections.

Figure 21-4. Typical SPIx Host, Frame Host Connection Diagram
Note:
  1. In Framed SPI mode, the SSx pin is used to transmit/receive the Frame Synchronization pulse.
  2. Framed SPI mode requires the use of all four pins (i.e., using the SSx pin is not optional).
Figure 21-5. Typical SPIx Host, Frame Client Connection Diagram
Note:
  1. In Framed SPI mode, the SSx pin is used to transmit/receive the Frame Synchronization pulse.
  2. Framed SPI mode requires the use of all four pins (i.e., using the SSx pin is not optional).