38.3.4 Interrupts

Table 38-6. Available Interrupt Vectors and Sources
Interrupt Vector Name	Interrupt Source Name	Description	Condition
NMI	ERROR	Non-Maskable Interrupt from a CRC Scan failure	ERROR in CRCSCAN.STATUSA and NMIEN in CRCSCAN.CTRLA is ‘`1`’
CRCSCAN	PERIOD	The scan period is done	PERIOD in CRCSCAN.INTFLAGS and PEREN in CRCSCAN.CTRLA is ‘`1`’
CRCSCAN	DONE	The scan of an entire Flash region is done	DONE in CRCSCAN.INTFLAGS is ‘`1`’

When the CRCSCAN interrupt condition occurs, the DONE or PERIOD flag in the Interrupt Flags (CRCSCAN.INTFLAGS) register is set to ‘1’. The flag is cleared by writing a ‘1’ to the bit position.

Enable the Enable Periodic Timer (PEREN) bit in the Control A (CRCSCAN.CTRLA) register to get a PERIOD interrupt.

A Non-Maskable Interrupt (NMI) is enabled by writing a ‘1’ to the Enable NMI Trigger (NMIEN) bit in the CTRLA register. An NMI is generated when the CRC Error (ERROR) bit in the Status A (CRCSCAN.STATUSA) register is ‘1’, and the NMIEN bit in the CRCSCAN.CTRLA register is ‘1’. The NMI request remains active until a System Reset or by writing a ‘1’ to the Reset CRCSCAN (RESET) bit in the CRCSCAN.CTRLA register.