Atmel Xplained Pro Evaluation Kit for the ATSAMD21J18A Microcontroller ATSAMD21-XPRO ATSAMD21-XPRO Fiche De Données
Codes de produits
ATSAMD21-XPRO
400
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181C–SAM-D21_Datasheet–07/2014
See the
register for details on how to clear interrupt flags. The EVSYS has one common interrupt request line
for all the interrupt sources. The user must read the INTFLAG register to determine which interrupt condition is present.
Note that interrupts must be globally enabled for interrupt requests to be generated.
23.6.3.1 The Overrun Channel x Interrupt
The Overrun Channel x interrupt flag in the Interrupt Flag Status and Clear register (INTFLAG.OVRx) is set and the
optional interrupt is generated in the following two cases:
optional interrupt is generated in the following two cases:
z
At least one of the event users on channel x is not ready when a new event occurs. Event user will not be ready if
that user is disabled or not able to handle the incoming event.
that user is disabled or not able to handle the incoming event.
z
An event occurs when the previous event on channel x has not yet been handled by all event users. This can
happen when an user is handling event slowly which means that a new event is generated when previous one is
already pending
happen when an user is handling event slowly which means that a new event is generated when previous one is
already pending
INTFLAG.OVRx will be set when using a synchronous or resynchronized path, but not when using an asynchronous
path.
path.
23.6.3.2 The Event Detected Channel x Interrupt
The Event Detected Channel x interrupt flag in the Interrupt Flag Status and Clear register (INTFLAG.EVDx) is set when
an event coming from the event generator configured on channel x is detected.
an event coming from the event generator configured on channel x is detected.
INTFLAG.EVDx will be set when using a synchronous and resynchronized path, but not when using an asynchronous
path.
path.
23.6.4 Sleep Mode Operation
The EVSYS can generate interrupts to wake up the device from any sleep mode.
Some event generators can generate an event when the system clock is stopped. The generic clock
(GCLK_EVSYS_CHANNELx) for this channel will be restarted if the channel uses a synchronized path or a
resynchronized path, without waking the system from sleep. The clock remains active only as long as necessary to
handle the event. After the event has been handled, the clock will be turned off and the system will remain in the original
sleep mode. This is known as SleepWalking. When an asynchronous path is used, there is no need for the clock to be
activated for the event to be propagated to the user.
(GCLK_EVSYS_CHANNELx) for this channel will be restarted if the channel uses a synchronized path or a
resynchronized path, without waking the system from sleep. The clock remains active only as long as necessary to
handle the event. After the event has been handled, the clock will be turned off and the system will remain in the original
sleep mode. This is known as SleepWalking. When an asynchronous path is used, there is no need for the clock to be
activated for the event to be propagated to the user.
On a software reset, all registers are set to their reset values and any ongoing events are canceled.