GD32F10x User Manual
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Figure 16-9. Break frame occurs during idle state
, if a break frame occurs
during the idle state on the RX pin, the USART receiver will receive an all ‘0’ frame, with an
asserted FERR status.
Figure 16-9. Break frame occurs during idle state
frame0
frame1
frame2
1 frame time
USART_DATA
data0
data1
0000000
0
data2
FERR
RX pin
LBDF
As shown in
Figure 16-10. Break frame occurs during a frame
, if a break frame occurs
during a frame on the RX pin, the FERR status will be asserted for the current frame.
Figure 16-10. Break frame occurs during a frame
frame0
frame2
USART_DATA
data0
data1
data2
FERR
RX pin
LBDF
1 frame time
frame1
16.3.9.
Synchronous mode
The USART can be used for full-duplex synchronous serial communications only in master
mode, by setting the CKEN bit in USART_CTL1. The LMEN bit in USART_CTL1 and SCEN,
HDEN, IREN bits in USART_CTL2 should be reset in synchronous mode. The CK pin is the
synchronous USART transmitter clock output, and can be only activated when the TEN bit is
enabled. No clock pulse will be sent through the CK pin during the start bit and stop bit
transmission. The CLEN bit in USART_CTL1 can be used to determine whether the clock is
output or not during the last (address flag) bit transmission. The CPH bit in USART_CTL1 can
be used to determine whether data is captured on the first or the second clock edge. The CPL
bit in USART_CTL1 can be used to configure the clock polarity in the USART synchronous
idle state.
The CPL, CPH and CLEN bits in USART_CTL1 determine the waveform on the CK pin.
Software can only change them when the USART is disabled (UEN=0).
If the REN bit in USART_CTL0 is set, the receiver works differently from the normal USART
reception method. The receiver samples the data on the capture edge of the CK pin without
any oversampling.
Summary of Contents for GD32F10 Series
Page 63: ...GD32F10x User Manual 63 programmed during the chip production ...
Page 117: ...GD32F10x User Manual 117 010 1 0 011 0 9 ...
Page 416: ...GD32F10x User Manual 416 shadow register updates every update event ...
Page 427: ...GD32F10x User Manual 427 value ...
Page 518: ...GD32F10x User Manual 518 These bits are not used in SPI mode ...