Nations N32G45 Series, User Manual

Page: 640 / 838

640 / 838
Nations Technologies Inc.
Tel
：
+86-755-86309900
Email
：
info@nationstech.com
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
Figure 23-4 configuration stop bit
Break frame
Use USART_CTRL1.SDBRK to send the break character. When there is 8-bit data, the break frame consists of 10
bits of low level, followed by a stop bit; when there is 9-bit data, the break frame consists of 11 bits of low level,
followed by a stop bit.
After the break frame is sent, USART_CTRL1.SDBRK is cleared by hardware, and the stop bit of the break frame is
being sent. Therefore, to send a second break frame, USART_CTRL1.SDBRK should be set after the stop bit of the
previous break frame has been sent.
If software resets the USART_CTRL1.SDBRK bit before starting to send the break frame, the break frame will not
be sent.
Transmitter process
1. Enable USART_CTRL1.UEN to activate USART;
2. Configure the transmitter's baud rate, data bit length, parity bit (optional), the number of stop bits or DMA
configuration;
3. Activate the transmitter (USART_CTRL1.TXEN);
4. Send each data to be sent to the USART_DAT register through the CPU or DMA, and the write operation to the
USART_DAT register will clear USART_STS.TXDE;
5. After writing the last data word in the USART_DAT register, wait for USART_STS.TXC =1, which indicates
8-bit Word length (WL bit is reset)
Data frame
Stat
bit
Stop
bit
Start
bit
**
CLOCK
bit0 bit1 bit2 bit3 bit5 bit4 bit6 bit7
Data frame
Stat
bit
1.5Stop bits
Start
bit
bit0 bit1 bit2 bit3 bit5 bit4 bit6 bit7
Data frame
Stat
bit
2Stop bits
Start
bit bit0 bit1 bit2 bit3 bit5 bit4 bit6 bit7
Data frame
Stat
bit
0.5Stop bit
Start
bit
bit0 bit1 bit2 bit3 bit5 bit4 bit6 bit7
Data frame
1 Stop bit
1.5 Stop bits
2 Stop bits
0.5 Stop bit
bit7 can be the parity bit
Data frame
Data frame
Data frame
bit7 can be the parity bit
bit7 can be the parity bit
bit7 can be the parity bit