Polycom VS4000 User Manual

Chapter 5 - Supporting Advanced Users

© Polycom, Inc.

105

RS-232 Interface

In Control Mode, the ViewStation EX, ViewStation FX, or VS4000 is 
under the control of the PC or other device connected to its RS-232 
port. 

Pass-Thru Mode allows two endpoints to pass data from one unit’s 
RS-232 port to the other unit’s RS-232 port, using the H.320 call as 
the connection. Pass-Thru Mode is a proprietary feature that is only 
available if both endpoints are ViewStation EX, ViewStation FX, or 
VS4000 systems. Pass-Thru Mode is available only in H.320 mode 
(ISDN or V.35/RS-449/RS-530) calls. It is not available in H.323 (IP) 
video calls or multi-point calls.

When using Pass-Thru Mode, both endpoints must be set to the 
same baud rate.

Four-way call: 
presentation mode

None

Far

Near

Far (2)

Far (3)

Four-way call: 
full-screen mode

None

Far

Near

Far (2)

Far (3)

Table 5-1.  Expected Display for Each Monitor (Continued)