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CMS80F731x Reference Manual
20.9 SPI Timing Diagram
20.9.1
Master Mode Transmission
When the clock polarity of the SPI is CPOL=0 and the clock phase CPHA=1, the NSS in SPI master mode is the clK of the
system clock after the low level, the MOSI starts to output, and the DATA of the MOSI is output on the rising edge of the SCLK
clock. The master mode timing diagram is shown in the following figure:
D7
D6
D5
D4
D3
D2
D1
D0
MOSI
NSS
1 CLK
1 CLK
SCLK
20.9.2
Slave Mode Transmission
When the clock polarity of the SPI is CPOL=0 and the clock phase is CPHA=1, the data on miso starts to output after the
falling edge of the NSS line. Miso data output differs from the falling edge of the NSS by a maximum of 1 system clock CLK.
The slave mode timing diagram is shown in the following figure:
D7
D6
D5
D4
D3
D2
D1
MISO
NSS
SCLK
max 1 CLK
max 1 CLK
D0