Keep the same state for the
SYSREFREQ pin when switching from request mode to windowing mode and back to
request mode. For example, if the SYSREFREQ pin is high (or low) when windowing
mode starts, make sure the pin state is high (or low) again after windowing mode
ends before programing SYSREFREQ_MODE field to other mode.
The SYSREFREQ pin must be set low when switching from or to SYNC mode.