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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
Summary of Contents for NS9215
Page 1: ...NS9215 Hardware Reference 90000847_C Release date 10 April 2008...
Page 3: ......
Page 4: ......
Page 26: ...26 Hardware Reference NS9215...
Page 44: ...P I N O U T 26 5 System clock 44 Hardware Reference NS9215 System clock drawing...
Page 52: ...P I N O U T 26 5 Power and ground 52 Hardware Reference NS9215...
Page 80: ...I O C O N T ROL M O D U L E Memory Bus Configuration register 80 Hardware Reference NS9215...
Page 136: ...WOR KI N G W I TH T H E C P U Noncachable instruction fetches 136 Hardware Reference NS9215...
Page 202: ...S Y S T E M C O N T RO L M OD U L E RTC Module Control register 202 Hardware Reference NS9215...
Page 354: ...E X T E R N A L D M A DMA Peripheral Chip Select register 354 Hardware Reference NS9215...
Page 472: ...R E A L TI M E C L O C K M O D U L E General Status register 472 Hardware Reference NS9215...
Page 512: ...TI M I NG Clock timing 512 Hardware Reference NS9215...
Page 515: ...PA CKA GING Processor Dimensions www digiembedded com 515...
Page 516: ...PA CKA GING Processor Dimensions 516 Hardware Reference NS9215...