62
8331B–AVR–03/12
Atmel AVR XMEGA AU
• Bit 2 – SINGLE: Single-Shot Data transfer
Setting this bit enables the single-shot mode. The channel will then do a burst transfer of
BURSTLEN bytes on the transfer trigger. A write to this bit will be ignored while the channel is
enabled.
• Bit 1:0 – BURSTLEN[1:0]: Burst Mode
These bits decide the DMA channel burst mode according to Table 5-3 on page 62. These bits
cannot be changed if the channel is busy.
Table 5-3. DMA channel burst mode.
BURSTLEN[1:0] Group Configuration Description
00 1BYTE 1 byte burst mode
01 2BYTE 2 bytes burst mode
10 4BYTE 4 bytes burst mode
11 8BYTE 8 bytes burst mode
Table 5-4. Summary of triggers, transcation complete flag and channel disable according to
DMA channel configuration.
REPEAT SINGLE REPCNT Trigger Flag Set After Channel Disabled After
0 0 0 Block 1 block 1 block
0 0 1 Block 1 block 1 block
0 0 n > 1 Block 1 block 1 block
0 1 0 BURSTLEN 1 block 1 block
0 1 1 BURSTLEN 1 block 1 block
0 1 n > 1 BURSTLEN 1 block 1 block
1 0 0 Block Each block Each block
1 0 1 Transaction 1 block 1 block
1 0 n > 1 Transaction n blocks n blocks
1 1 0 BURSTLEN Each block Never
1 1 1 BURSTLEN 1 block 1 block
1 1 n > 1 BURSTLEN n blocks n blocks