Digi NS9215 - Manual (Page 435)

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S E R I A L C O N T R O L M O D U L E : S P I
SPI clocking modes
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S P I c l o c k i n g m o d e s
There are four SPI clocking modes. Each mode’s characteristics are defined by the
idle value of the clock, which clock edge captures data, and which clock edge drives
data. The MODE field in the SPI Configuration register specifies the timing mode.
Timing modes
Clocking mode
diagrams
The next two diagrams show the four SPI clocking modes. SPI Mode0 and SPI Mode3
are the most commonly used modes.
SPI Mode0 and Mode3 functional timing
SPI Mode1 and Mode2 functional timing
SPI mode SPI CLK Idle SPI DATA IN
capture edge SPI DATA OUT
drive edge
0 Low Rising Falling
1 High Falling Rising
2 Low Falling Rising
3 High Rising Falling
Mode 3
Mode 0
Mode 3
Mode 0
CS#
CLK
SIN / SOUT
Capture Edge Launch Edge
Mode 1
Mode 2
Mode 1
Mode 2
CS#
CLK
SIN / SOUT
Capture Edge Launch Edge