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XMEGA A [MANUAL]
8077I–AVR–11/2012
Figure 20-2. SPI transfer modes.
20.6
DMA Support
DMA support on the SPI module is available only in slave mode. The SPI slave can trigger a DMA transfer as one byte
has been shifted into the DATA register. It is possible, however, to use the XMEGA USART in SPI mode and then have
Bit 1
Bit 6
LSB
MSB
Mode 0
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
Mode 2
SS
MSB
LSB
Bit 6
Bit 1
Bit 5
Bit 2
Bit 4
Bit 3
Bit 4
Bit 2
Bit 5
MSB first (DORD = 0)
LSB first (DORD = 1)
Mode 1
SAMPLE I
MOSI/MISO
CHANGE 0
MOSI PIN
CHANGE 0
MISO PIN
Mode 3
SS
MSB
LSB
Bit 6
Bit 1
Bit 5
Bit 2
Bit 4
Bit 3
Bit 4
Bit 2
Bit 5
Bit 1
Bit 6
LSB
MSB
MSB first (DORD = 0)
LSB first (DORD = 1)