Envoy Application Programming Manual

Table Of Contents
BISYNC Multipoint Tributary Protocol
Envoy Application Programming Manual427159-001
5-38
Programming Examples
Example 5-13 shows the control sequences that take place when the station is polled and
sends a message to the supervisor station.
Example 5-13. Tributary Responds to a Poll
Tributary (Local) Supervisor (Remote)
poll state = inactive
select state = active
CALL READ
| | <-- EOT SYN SYN PA ENQ (poll)
| EOT -->
|
message to be sent
poll state set = active using CHANGELIST
|
| <-- EOT SYN SYN PA ENQ (poll)
(READ completes)
error = 166
line state = WRITE
MCW.<8:15> = 0
CALL WRITE
| message 1 -->
|
|
| <-- ACK0
(WRITE completes)
error = 0
line state = WRITE
poll state set = inactive using CHANGELIST
CALL READ
| EOT -->
|
| <-- EOT SYN SYN PA ENQ (poll)
| EOT -->
|
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