ACT Update Disable

When Active Clock Tuning is enabled, the OSCTUNE register is continuously updated every ACT clock cycle. The ACT Update Disable (ACTUD) bit can be used to suspend updates to the OSCTUNE register. When ACTUD is set (ACTUD = 1), updates to OSCTUNE are suspended, although the module continues to operate. The last value written to OSCTUNE is used for tuning, and the ACTLOCK bit is continually updated for each ACT cycle. When ACTUD is clear (ACTUD = 0), the module updates OSCTUNE register every ACT cycle.