11.2.3 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.