GD32F20x User Manual
546
Pin Name
Direction
Description
single master or (NSSDRV=0) for multi-master application.
Slave in Hardware NSS Mode: NSS input, as a chip select
signal for slave.
21.4.2.
Quad-SPI configuration
SPI is in single wire mode by default and enters into Quad-SPI mode after QMOD bit in
SPI_QCTL register is set (only available in SPI0). Quad-SPI mode can only work at master
mode.
Software is able to drive IO2 and IO3 pins high in normal Non-Quad-SPI mode by using
IO23_DRV bit in SPI_QCTL register.
The SPI is connected to external devices through 6 pins in Quad-SPI mode:
Table 21-2. Quad-SPI signal description
Pin Name
Direction
Description
SCK
O
SPI Clock Output
MOSI
I / O
Transmission or Reception Data 0 line
MISO
I / O
Transmission or Reception Data 1 line
IO2
I / O
Transmission or Reception Data 2 line
IO3
I / O
Transmission or Reception Data 3 line
NSS
O
NSS output
21.5.
SPI function overview
21.5.1.
SPI clock timing and data format
CKPL and CKPH bits in SPI_CTL0 register decide the timing of SPI clock and data signal.
The CKPL bit decides the SCK level when idle and CKPH bit decides either first or second
clock edge is a valid sampling edge.
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...