Nondialed User-Initiated Call State Machine - Polycom ViewStation EX User Manual

Appendix C

Nondialed User-Initiated Call State Machine

State
1 Initial State:
DTR = 0 <note 3>
RTS = 0 <note 2>
CRQ = 0
USER INITIATES CALL
2 DTR = 1<note 3>
3 RTS = 1<note 2>
4
5 DATA FLOW STARTS
User Hang-up
6 RTS = 0 <note 2>
DTR = 0 <note 3>
CRQ = 0
All signals go low if Far End or User hang-up is
detected.
7 IDLE
DTR = 0 <note 3>
RTS = 0 <note 2>
CRQ = 0
© Polycom, Inc.
ViewStation Signals
Note 1: DSR is not used as a ring-in indicator if DSR is set to
ANSWER in the V.35 Advanced Configuration screen.
Note 2: RTS does not act as shown but acts as a resync-pulse if
Security/Crypto-Resync is set to ON.
Note 3: DTR does not act as shown but remains at a high voltage if
DTR is set to ON in the V.35 Advanced Configuration screen.
Note 4: If DCD filter is set to ON in the V.35 Advanced
Configuration screen, the system does not react to a low DCD until
DCD has been low for 60 seconds.
Network Equipment Signals
Initial State:
RI = 0
DLO = 0
ACR = 0
DSR = 0
DCD = 0 to 1
DATA FLOW STARTS
Far End Hang-up
DSR= 1 to 0, OR DCD= 1 to 0
A falling edge on DSR or DCD is interpreted by
the ViewStation as a Hang-up.
<note 4>
IDLE
RI = 0
DLO = 0
ACR = 0
DSR = 0
197
V.35 Technical Information
ViewStation User Guide