Datasheet

Figure 31-3. Static Priority
Highest Channel
Lowest Channel
Highest Priority
Lowest Priority
Channel N
Channel 0
Channel x+1
Channel x
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The dynamic arbitration scheme available in the Event System is round-robin. Round-robin arbitration is
enabled by writing PRICTRL.RREN to one. With the round-robin scheme, the channel number of the last
channel being granted access will have the lowest priority the next time the arbiter has to grant access to
a channel, as shown below. The channel number of the last channel being granted access, will be stored
in the Channel Priority Number bit group in the Priority Control register (PRICTRL.PRI).
Figure 31-4. Round-Robin Scheduling
Channel N
Channel N
Channel 0
Channel x
Channel x+1
Channel x last acknowledge request
Channel (x+1) last acknowledge request
Channel 0
Channel x
Channel x+1
Channel x+2
Lowest Priority
Highest Priority
Highest Priority
Lowest Priority
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.
.
.
.
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The Channel Pending Interrupt register (INTPEND) also offers the possibility to indirectly clear the
interrupt flags of a specific channel. Writing a flag to one in this register, will clear the corresponding
interrupt flag of the channel specified by the INTPEND.ID bits.
SAM D5x/E5x Family Data Sheet
EVSYS – Event System
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 853