In-Bound Call State Machine - Polycom ViewStation EX User Manual

Appendix C
State
15 RTS = 0 <note 2>
DTR = 0 <note 3>
CRQ = 0
All signals go low if Far End or User hang-up is
detected.
16 IDLE
DTR = 0 <note 3>
RTS = 0 <note 2>
CRQ = 0

In-bound 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 Wait 10 ms
4 CRQ = 1
5
6 Set Digit (NB1,NB2,NB3,NB4)
7 DPR = 1
8
© Polycom, Inc.
ViewStation Signals
Note 1: DSR is used as a ring-in indicate if DSR is set to ANSWER
in the V.35 Advanced Configuration screen.
Note 2: RTS does not act as shown but act 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.
ViewStation Signals
Network Equipment Signals
DSR = 1 to 0, OR DCD = 1 to 0
A falling edge on DSR or DCD is interpreted by
the VS4000 as a hang-up.
IDLE
RI = 0
DLO = 0
ACR = 0
DSR = 0
Network Equipment Signals
Initial State:
RI = 0
DLO = 0
ACR = 0
DSR = 0
PND = 1
PND = 0
195
V.35 Technical Information
ViewStation User Guide