Envoy Application Programming Manual

BISYNC Centralized Multipoint Supervisor Protocol
Envoy Application Programming Manual—427159-001
4-32
WRITE Procedure
Table 4-13 lists the possible errors and their descriptions while the line is in the WRITE
state.
Example 4-11. Continuation WRITE (Line in WRITE State)
Supervisor (Local) Tributary (Remote)
line state = WRITE
CALL WRITE(...)
| message 2 -->
| <-- ACK0
(WRITE completes)
error = 0
line state = WRITE
Table 4-13. WRITE File-System Errors (page 1 of 2)
Error State Description Resultant Line State
0 No error. The message in the buffer of the applica-
tion process is written to the tributary station.
WRITE
160 Request is invalid for device state; protocol error. unknown
161 Impossible event occurred for line state. unknown
163 EOT received. An EOT was received while waiting
for an acknowledgment of the first message sent.
CONTROL
165 RVI received. The tributary transmitted a reverse
interrupt sequence as a positive acknowledgment to
the message.
WRITE
166 ENQ in response to selection. WRITE
171 No response to selection. The response was solic-
ited the number of times specified by the retry
value.
WRITE
172 Reply not proper for protocol. The data received
when the message was transmitted was not proper
for the BISYNC protocol.
WRITE
173 Transmission error. A NAK sequence in response to
the text was received the number of times specified
by the retry value.
WRITE
174 WACK received. A WACK sequence was received
as the text acknowledgment.
CONTROL
175 Incorrect ACK received. The ACK received was out
of sequence with the expected ACK value
WRITE