MSI MS-9A69-U Series Manual page 13

RS232/422/485 Serial Port: COM1 ~ COM2
3
The serial port is a 16550A high speed communications port that sends/
receives 16 bytes FIFOs. It supports barcode scanners, barcode printers, bill
printers, credit card machine, etc.
RS232
PIN SIGNAL
1 DCD
2 RXD
3 TXD
4 DTR
5 GND
6 DSR
7 RTS
8 CTS
9 POWER
RS422
PIN SIGNAL
1 TXD-
2 TXD+
3 RXD+
4 RXD-
5 GND
6 NC
7 NC
8 NC
9 NC
RS485
PIN SIGNAL
1 D-
2 D+
3 NC
4 NC
5
GND
6 NC
7 NC
8 NC
9 NC
Power Button
4
Press the button to turn the system on or off.
Microphone Jack
5
This connector is provided for microphones.
1 5
6 9
DESCRIPTION
Data Carrier Detect
Receive Data
Transmit Data
Data Terminal Ready
Ground
Data Set Ready
Request To Send
Clear To Send
5V or 12V selected by GPIO (BIOS)
DESCRIPTION
Transmit Data, Negative
Transmit Data, Positive
Receive Data, Positive
Receive Data, Negative
Ground
No Connection
No Connection
No Connection
No Connection
DESCRIPTION
Data, Negative
Data, Positive
No Connection
No Connection
Ground
No Connection
No Connection
No Connection
No Connection
MS-9A69-U Series
1-5