DCB Ether Series, Руководство пользователя

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Specifications
55
2-Wire RS-485 Interface Pinout
Serial Port Pin Assignments
Pin Signal Name Type
1 No Connection N/A
2 No Connection N/A
3 Receive Data (Rx-) In/Out
4 No Connection N/A
5 Signal Ground (GND) N/A
6 No Connection N/A
7 No Connection N/A
8 Receive Data (Rx+) In/Out
9 No Connection N/A
RS-485 2-wire Fan-out
Since this unit is most often used as an RS-485 2-wire end-point,
it is delivered with terminating resistors installed internally.
With this termination installed the RS-485 2-wire interface will
reliably drive three RS-485 loads.
If more than 3 devices are required, the terminating resistor pack
may be removed. Without the terminating resistor pack, up to
31 devices may be used on the RS-485 line. However, all RS-485
standard rules must still be observed.