Serial Connections; Serial Mode And Terminator Resistor Selection; Table 2.4: Com1 - Com4 Serial Port Setting - Advantech UNO-1110 User Manual

2.4

Serial Connections

2.4.1

Serial Mode and Terminator Resistor Selection

UNO-1110 provides 5 serial Com ports, COM1 - COM4 provide RS-232/422/485, and
COM5 provides RS-485. The default settings of COM1 - COM4 are RS-232. Users
could change COM1 - COM4 Port serial types to RS-422 or RS-485 by SW3/SW4
DIP switch selection located on rear side of the UNO-1110 system.
You can enable RS-422/485 terminator resistors if necessary to match impedance.
Especially in fields with electric noise, enabling terminal resistors is helpful to stabi-
lize communications. Make sure that both sides of the RS-422 or RS-485 communi-
cation ports are installed on BUS.
Users could change COM1 - COM4 serial port type and RS-422/485 terminator resis-
tor settings by SW3/Serial Port Setting DIP switch located on rear side of the UNO-
1110 system according to the table below.

Table 2.4: COM1 - COM4 Serial Port Setting

COM1/COM3
DIP Switch
COM2/COM4
Serial Mode
DIP Switch
RS-232 Standard Mode
RS-485 Auto Flow Mode
RS-485 Auto Flow Mode
RS-422 Master
RS-422 Master
Receiver Termination Mode
N/A
120 Ohms Terminator Resistor
No Termination
120 Ohms Terminator Resistor
No Termination
9 UNO-1110 User Manual