SWCU191 February 2022 CC1311P3 , CC1311R3 , CC2651P3 , CC2651R3 , CC2651R3SIPA
When the SPO clock polarity control bit is clear, the bit produces a steady-state low value on the SSIn_CLK pin. If the SPO bit is set, the bit places a steady-state high value on the SSIn_CLK pin when data is not being transferred.