Nuvoton NuMicro MS51PC0AE - Page 372

MS51
Nov. 28, 2019 Page 372 of 491 Rev 1.00
MS51 32K SERIES TECHNICAL REFERENCE MANUAL
6.9.7 Control Register of Serial Port
SCON – Serial Port Control
Register
SFR Address
Reset Value
SCON
98H, All page, Bit addressable
0000_0000 b
7
6
5
4
3
2
1
0
SM0/FE
SM1
SM2
REN
TB8
RB8
TI
RI
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit
Name
Description
7
SM0/FE
Serial port mode select
SMOD0 (PCON.6) = 0:
See Table 6.9-1 Serial Port UART0 Mode / baudrate Description for details.
SMOD0 (PCON.6) = 1:
SM0/FE bit is used as frame error (FE) status flag. It is cleared by software.
0 = Frame error (FE) did not occur.
1 = Frame error (FE) occurred and detected.
6
SM1
5
SM2
Multiprocessor communication mode enable
The function of this bit is dependent on the serial port 0 mode.
Mode 0:
This bit select the baud rate between FSYS/12 and FSYS/2.
0 = The clock runs at FSYS/12 baud rate. It maintains standard 8051compatibility.
1 = The clock runs at FSYS/2 baud rate for faster serial communication.
Mode 1:
This bit checks valid stop bit.
0 = Reception is always valid no matter the logic level of stop bit.
1 = Reception is valid only when the received stop bit is logic 1 and the received data matches
“Given” or “Broadcast” address.
Mode 2 or 3:
For multiprocessor communication.
0 = Reception is always valid no matter the logic level of the 9th bit.
1 = Reception is valid only when the received 9th bit is logic 1 and the received data matches
“Given” or “Broadcast” address.
4
REN
Receiving enable
0 = Serial port 0 reception Disabled.
1 = Serial port 0 reception Enabled in Mode 1,2, or 3. In Mode 0, reception is initiated by the
condition REN = 1 and RI = 0.
3
TB8
9th transmitted bit
This bit defines the state of the 9th transmission bit in serial port 0 Mode 2 or 3. It is not used in
Mode 0 or 1.