![](http://datasheet.mmic.net.cn/100000/IF180C52TXXX-20R_datasheet_3493957/IF180C52TXXX-20R_201.png)
201
32099I–01/2012
AT32UC3L016/32/64
writing a zero to CEN the other bits in GCCTRL should not be changed until CEN reads as zero,
to avoid glitches on the generic clock. The generic clocks will be automatically re-enabled when
waking from sleep.
13.5.13.3
Changing clock frequency
When changing the generic clock frequency by changing OSCSEL or DIV, the clock should be
disabled before being re-enabled with the new clock source or division setting. This prevents
glitches during the transition.
13.5.13.4
Generic clock allocation
The generic clocks are allocated to different functions as shown in the “Generic Clock Allocation”
table in the SCIF Module Configuration section.
13.5.14
Interrupts
The SCIF has the following interrupt sources:
AE - Access Error:
– A protected SCIF register was accessed without first being correctly unlocked.
BRIFARDY - Backup Register Interface Ready.
– A 0 to 1 transition on the PCLKSR.BRIFARDY bit is detected.
DFLL0RCS - DFLL Reference Clock Stopped:
– A 0 to 1 transition on the PCLKSR.DFLLRCS bit is detected.
DFLL0RDY - DFLL Ready:
– A 0 to 1 transition on the PCLKSR.DFLLRDY bit is detected.
DFLL0LOCKLOSTA - DFLL lock lost on Accurate value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTA bit is detected.
DFLL0LOCKLOSTF - DFLL lock lost on Fine value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTF bit is detected.
DFLL0LOCKLOSTC - DFLL lock lost on Coarse value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKLOSTC bit is detected.
DFLL0LOCKA - DFLL Locked on Accurate value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKA bit is detected.
DFLL0LOCKF - DFLL Locked on Fine value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKF bit is detected.
DFLL0LOCKC - DFLL Locked on Coarse value:
– A 0 to 1 transition on the PCLKSR.DFLLLOCKC bit is detected.
BODDET - Brown out detection:
– A 0 to 1 transition on the PCLKSR.BODDET bit is detected.
SM33DET - Supply Monitor 3.3V Detector:
– A 0 to 1 transition on the PCLKSR.SM33DET bit is detected.
VREGOK - Voltage Regulator OK:
– A 0 to 1 transition on the PCLKSR.VREGOK bit is detected.
OSC0RDY - Oscillator Ready:
– A 0 to 1 transition on the PCLKSR.OSC0RDY bit is detected.