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
. 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