GD32W51x User Manual
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Figure 18-6. Configuration step when using DMA for USART reception
Set the address of USART_RDATA as
the DMA source address
Set the address of the buffer in internal
sram as the DMA destination address
Set the number of data as the DMA
transfer number
Set other configurations of DMA, interrupt
enable, priority, etc
Enable the DMA channel for USART
.
When the number of the data received by USART reaches the DMA transfer number, an end
of transfer interrupt can be generated in the DMA module.
18.3.6.
Hardware flow control
The hardware flow control function is realized by the nCTS and nRTS pins. The RTS flow
control is enabled by writing ‘1’ to the RTSEN bit in USART_CTL2 and the CTS flow control
is enabled by writing ‘1’ to the CTSEN bit in USART_CTL2.
Figure 18-7. Hardware flow control between two USARTs
USART 1
TX module
RX module
USART 2
RX module
TX module
TX
RX
nCTS
nRTS
RX
TX
nRTS
nCTS