Datasheet

610
42023E–SAM–07/2013
ATSAM4L8/L4/L2
ter/slave pair must use the same configuration, and the master must be reconfigured if it is to
communicate with slaves using different configurations. See Figures 24-43 and 24-44.
Figure 24-43. SPI Transfer Format (CPHA=1, 8 bits per transfer)
Figure 24-44. SPI Transfer Format (CPHA=0, 8 bits per transfer)
Table 24-16. SPI Bus Protocol Modes
MR.CPOL MR.CPHA SPI Bus Protocol Mode
01 0
00 1
11 2
10 3
CLK cycle (for reference)
CLK
(CPOL= 1)
MOSI
SPI Master ->TXD
SPI Slave ->RXD
MISO
SPI Master ->RXD
SPI Slave ->TXD
NSS
SPI Master ->RTS
SPI Slave ->CTS
MSB
MSB
1
CLK
(CPOL= 0)
3
5
6
78
LSB
1234
6
65
5
43
21
LSB
24
CLK cycle (for reference)
CLK
(CPOL= 0)
CLK
(CPOL= 1)
MOSI
SPI Master -> TXD
SPI Slave -> RXD
MISO
SPI Master -> RXD
SPI Slave -> TXD
NSS
SPI Master -> RTS
SPI Slave -> CTS
MSB 6 5
MSB 6 5
4
43
32
21
1
LSB
LSB
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