GD32F20x User Manual
547
Figure 21-2. SPI timing diagram in normal mode
SCK (CKPH=0 CKPL=0)
SCK (CKPH=0 CKPL=1)
SCK (CKPH=1 CKPL=0)
SCK (CKPH=1 CKPL=1)
MOSI
MISO
NSS
D[0]
LF=1,FF16=0
D[0]
D[7]
D[7]
Figure 21-3. SPI timing diagram in Quad-SPI mode (CKPL=1, CKPH=1, LF=0)
D[5]
D[4]
D[6]
D[7]
D[0]
D[1]
D[2]
D[3]
D[5]
D[4]
D[6]
D[7]
D[0]
D[1]
D[2]
D[3]
SCK
MOSI
MISO
IO2
IO3
NSS(slave)
Capture
In normal mode, the length of data is configured by the FF16 bit in the SPI_CTL0 register.
Data length is 16 bits if FF16=1, otherwise is 8 bits.
The data frame length is fixed to 8 bits
in Quad-SPI mode.
Data order is configured by LF bit in SPI_CTL0 register, and SPI will first send the LSB if
LF=1, or the MSB if LF=0.
21.5.2.
NSS function
Slave Mode
When slave mode is configured (MSTMOD=0), SPI gets NSS level from NSS pin in hardware
NSS mode (SWNSSEN = 0) or from SWNSS bit in software NSS mode (SWNSSEN = 1) and
transmits/receives data only when NSS level is low. In software NSS mode, NSS pin is not
used.
Содержание GD32F20 Series
Страница 1: ...GigaDevice Semiconductor Inc GD32F20x ARM Cortex M3 32 bit MCU User Manual Revision 2 2 Oct 2019 ...
Страница 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Страница 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Страница 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
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Страница 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...