26.6.6. Events
The DMAC can generate the following output events:
•
Channel (CH): Generated when a block transfer for a given channel has been completed, or when
a beat transfer within a block transfer for a given channel has been completed. Refer to
Setting the Channel Control B Event Output Enable bit (CHCTRLB.EVOE=1) enables the corresponding
output event configured in the Event Output Selection bit group in the Block Transfer Control register
(BTCTRL.EVOSEL). Clearing CHCTRLB.EVOE=0 disables the corresponding output event.
The DMAC can take the following actions on an input event:
•
Transfer and Periodic Transfer Trigger (TRIG): normal transfer or periodic transfers on peripherals
are enabled
•
Conditional Transfer Trigger (CTRIG): conditional transfers on peripherals are enabled
•
Conditional Block Transfer Trigger (CBLOCK): conditional block transfers on peripherals are
enabled
•
Channel Suspend Operation (SUSPEND): suspend a channel operation
•
Channel Resume Operation (RESUME): resume a suspended channel operation
•
Skip Next Block Suspend Action (SSKIP): skip the next block suspend transfer condition
Setting the Channel Control B Event Input Enable bit (CHCTRLB.EVIE=1) enables the corresponding
action on input event. clearing this bit disables the corresponding action on input event. Note that several
actions can be enabled for incoming events. If several events are connected to the peripheral, any
enabled action will be taken for any of the incoming events. For further details on event input actions,
refer to
.
Related Links
26.6.7. Sleep Mode Operation
Each DMA channel can be configured to operate in any sleep mode. To be able to run in standby, the
RUNSTDBY bit in Channel Control A register (
.RUNSTDBY) must be written to '1'. The DMAC
can wake up the device using interrupts from any sleep mode or perform actions through the Event
System.
Note:
In standby sleep mode, the DMAC can only access RAM when it is not back biased
(PM.STDBYCFG.BBIASxx=0x0)
26.6.8. Synchronization
Not applicable.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
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