Polycom VSX3000 Integrator's Reference Manual page 65

The 8-pin mini-DIN female connector on the VSX system has the following
connections.
Pin Signal
1 Not used
2 Tx (output)
3 Rx (input)
4 DSR (input)
5 GND
6 DTR (output)
7 RTS (output)
8 CTS (input)
Shield GND
7
8
5
4
2 1
6
3
Cables
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