Com Port Headers; Com 0 And 2 (Rs232/Rs422/Rs485); Table 23 X26/X27 Pinout Description; Table 24 Dip Sw3 - Com Port Configuration - Congatec SMARC conga-SMC1 User Manual

4.11

COM Port Headers

The conga-SMC1 provides four COM ports:
• COM port 0 and 2 via ISL3333 transceiver
• COM port 1 and 3 via ISL3243E transceiver
4.11.1

COM 0 and 2 (RS232/RS422/RS485)

The conga-SMC1 provides COM port 0 on pin header X26 and COM port 2 on pin header X27. Both ports support RS 232 or RS422/RS485
voltage level. Use DIP SW3 to select the serial communication standard.
Note
1. If 120 ohm bus termination is required, add a termination resistor to the cable or cable adapter.
2. RS485 mode supports Tx output control and Rx echo cancellation if the attached module supports active-low RTS signal.
3. For 2-wire RS485, connect pin 2 to pin 5 and pin 3 to pin 4 externally.
Table 23 X26/X27 Pinout Description
Pin RS232 RS422/RS485
1 GND GND
2 TXD TX-
3 RTS# TX+
4 CTS# RX+
5 RXD RX-
Table 24 DIP SW3 - COM Port Configuration
Switch Configuration Description
SW3.1 OFF
ON
SW3.2 OFF
ON
Copyright © 2020 congatec AG
Description
Ground
Transmit Data/Transmit Data -
Request to Send/Transmit Data +
Clear to Send/Receive Data +
Receive Data/Receive Data -
COM 0 RS422/RS485 standard
COM 0 RS232 standard (default)
COM 2 RS422/RS485 standard
COM 2 RS232 standard (default)
SMC1m10
X26/X27
SW3
1 2 3 4
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