BERGHOF DC2004 - Serial Interfaces

USER HANDBOOK 2.0 | DC20XX, ET20XX, ECC21XX SLIM
Berghof Automation GmbH | Harretstrasse 1 | 72800 Eningen | www.berghof.com
Dialog-Controller-DC20XX_EN.docx
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5.2.8. Serial interfaces
The module has two serial communications interfaces (1x RS-232 and 1x RS-485), which are connected via
the common RJ45 plug X6.
Maximum baud rate for both interfaces: 115 kBd
Fig. 27: RS-232 / RS-485 interface X6
Pin assignment for RS-232 / RS-485 interface plug X6
Pin
Assignment / software interface
Pin
Assignment / software interface
1
RS-232 RX / COM 1
5
RS-485 Tx/Rx– / COM 2
2
RS-232 TX / COM 1
6
NC
3
NC
7
(reserved)
4
RS-485 Tx/Rx+ / COM 2
8
ISO GND
The RS-485 interface is “soft” terminated in the dialogue controller with 560 Ω.
If the interface is located at the start or end of the bus topology:
 Set switch S3 to ON in order to switch on the 120 Ω terminating resistor.
Fig. 28: RS-485 switchable terminating resistor