13.2.2.3.1 Motorola SPI Modes
Motorola SPI modes are shown in the following figures.
Single Frame Transfer – Mode 0: SPO = 0, SPH = 0
Multiple Frame Transfer – Mode 0: SPO = 0, SPH=0
Important:
- Between frames, the slave select (SPI_SS[x]) signal is asserted for the duration of the clock pulse.
- Between frames, the clock (SPI_CLK) is Low.
- Data is transferred to Most Significant Bit (MSB) first.
- The output enable (SPI_DOE_N) signal is asserted during the transmission and deasserted at the end of the transfer (after the last frame is sent).
Single Frame Transfer – Mode 1: SPO = 0, SPH = 1
Single Frame Transfer – Mode 2: SPO = 1, SPH = 0
Single Frame Transfer – Mode 3: SPO = 1, SPH = 1