Westermo Lynx-x08-F2G-S2 - Manual (Page 11)

11 6643-2220
RS-232
Position Signal Direction Description
No. 1 DSR Out Data Set Ready
No. 2 DCD Out Data Carrier Detect
No. 3 DTR In Data Terminal Ready
No. 4 SG – Signal Ground, not chassis ground
No. 5 RD Out Receive Data
No. 6 TD In Transmit Data
No. 7 CTS Out Clear To Send
No. 8 RTS In Request To Send
RS-422/485 (for more details see below)
Position Signal Direction Description
RS-422
(4-wire)
RS-485
(2-wire)
No. 1 T+ T+/R+ Out/In RS-422: Transmit
RS-485: Transmit/Receive
No. 2 T– T–/R– Out/In RS-422: Transmit
RS-485: Transmit/Receive
No. 3 R– – In RS-422: Receive
No. 4 – – – Not used
No. 5 – – – Not used
No. 6 R+ – In RS-422: Receive
No. 7 – – – Not used
No. 8 – – – Not used
Lynx DSS is equipped with internal termination that is configurable through software
in RS-422/485 mode. The following termination schemes are supported:
RS-422
No termination
Rx
Terminate Rx Terminate Tx
Tx
Rx
Tx
Rx
Tx
Rx
Tx
Terminate Tx and Rx
RS-485
No termination Termination
When the unit is powered-off or during reboot, any internal termination will be
disconnected from the signal lines.
Note: Due to that the port is configurable for both RS-232 and RS-422/485,
there are no fail-safe biasing available for RS-422/485 signals.