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Field
Name
R/W
Description
00: 1 stop bit
01: Reserved
10: 2 stop bits
11: Reserved
This bit can be
set only when USART is not enabled.
14
Reserved
15
SWAPEN
R/W
Swap TX/RX Pins Function Enable
0: Use according to standard allocation
1: The functions of TX and RX pins can be exchanged for use, and
they will work when crossing and interconnecting with other USART.
Set or cleared by software.
This bit can be set only when USART is not enabled.
16
RXINVEN
R/W
RX Pin Active Level Inversion Enable
0: Standard logic level (V
DD
=1/IDLE, Gnd=0/mark)
1: Reverse direction (V
DD
=0/mark, Gnd=1/IDLE), which works when
there is an external phase inverter on RX line.
Set or cleared by software.
This bit can be set only when USART is not enabled.
17
TXINVEN
R/W
TX Pin Active Level Inversion Enable
0: Standard logic level (V
DD
=1/IDLE, Gnd=0/mark)
1: Reverse direction (V
DD
=0/mark, Gnd=1/IDLE), which works when
there is an external phase inverter on TX line. Set or cleared by
software.
This bit can be set only when USART is not enabled.
18
BINVEN
R/W
Binary Data Inversion Enable
0: Positive/Direct logic (0=L, 1=H)
1: Negative/Reverse logic (0=H, 1=L)
Set or cleared by software.
This bit can be set only when USART is not enabled.
The check bit will be inverted when this bit is set.
19
MSBFEN
R/W
Most Significant Bit First Enable
0: The data of No. 0 bit immediately follows the start bit
1: The data of the most significant bit immediately follows the start bit
Set or cleared by software.
This bit can be set only when USART is not enabled.
20
ABRDEN
R/W
Auto Baud Rate Detection Enable
0: Disable
1: Enable
Set or cleared by software.
22:21
ABRDCFG
R/W
Auto Baud Rate Detection Mode Configure
00: Measure the start bit
01: Measure the falling edge
10: 0x7F frame detection
11: 0x55 frame detection
Set or cleared by software.
23
RXTODEN
R/W
Receive Timeout Detection Function Enable
0: Disable
1: Enable
Set or cleared by software.
Set this bit, and when it is detected that the RX line is idle for the
length of time configured by RXTO register, the RXTOFLG bit will be
set by hardware.