SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
To select the MCSPI peripheral mode, set the MCSPI_MODULCTRL[2] MS bit.
A MCSPI peripheral device can be connected to up to four external MCSPI controller devices but handles transactions with one MCSPI controller device at a time.
In peripheral mode, the MCSPI initiates data transfer on the data lines (SPIDAT[0] and SPIDAT[1]) when it is selected by an active control signal (SPIEN[i]) and receives an MCSPI clock (SPICLK) from the external MCSPI controller device. Only channel 0 can be configured as a peripheral but through the MCSPI_CHCONF_0[22-21] SPIENSLV bit field any of the SPIEN[i] signals can be used to select the MCSPI module. In peripheral mode and when the MCSPI_MODULCTRL[1] PIN34 is set to 0x0 (default behaviour), the MCSPI uses the edge of SPIEN[i] to detect word length. For this reason, SPIEN[i] must become inactive between each word.
When the MCSPI_MODULCTRL[1] PIN34 is set to 0x0, the MCSPI does not support SPIEN[i] active between MCSPI words. In this case, the MCSPI uses the edge to detect word length.
When the MCSPI_MODULCTRL[1] PIN34 is set to 0x1, a multiword transfer can be performed without needing the external MCSPI controller to deactivate SPIEN[i] between each word as in this case the MCSPI module works in 3-pin peripheral mode and SPIEN[i] is not needed.