In Synchronous Steering mode (MODE ='b001), changes to steering
selection registers take effect on the next rising edge of CWG Data (see figure below).
In Synchronous Steering mode, the output will always produce a complete waveform.
Important: Only the STRx bits are synchronized; the OVRx
bits are not synchronized.
Figure 1. Example of Synchronous Steering
(MODE = 
'b001)