Envoy Application Programming Manual
Table Of Contents
- What’s New in This Manual
- About This Manual
- 1 Application Programming With Envoy
- 7 ADM-2 Multipoint Supervisor Protocol
- 8 TINET Multipoint Supervisor Protocol
- 9 Burroughs Point-To-Point Protocol
- 10 Asynchronous Line Supervisor Protocol
- A ASCII Character Set
- B ASCII to EBCDIC Code Conversion
- C File-System Procedures
- D Statistics Messages
- E S-Series Changes to Envoy
- NonStop™ Himalaya S-Series Server Architecture
- G-Series Migration Considerations
- CBSENSEON and CFSENSEON Modifiers
- LEOTRESYN and NOLEOTRESYN Modifiers
- Treatment of Characters After the Termination Character
- Number of SYN Characters
- DTR Drop
- Reporting of Parity Error
- Half-Duplex Support for Asynchronous Lines
- Controller Replacement
- SYSGEN and COUP
- Unit Numbers
- FDX Line Changes
- No Support for Auto-Call Unit
- Glossary
- Index
BISYNC Centralized Multipoint Supervisor Protocol
Envoy Application Programming Manual—427159-001
4-14
Polling Type
If a polled station responds with text, the READ completes with the line in the READ
state and an error 0 (operation successful). Along with the text message, the polled
station returns a message control word (MCW), which contains the polled station's entry
number to the line buffer of the application process (see Message Formats
on
page 4-22).
If a polled station fails to respond or if an incorrect response is received, the READ
completes with an error indication; the application process returns the entry number of
the station in error in the message control word. In either case (that is, if text is received
or an error occurs), when polling resumes, the next station polled is the one after the
station causing the stoppage. For example, if entry number 2 is the last station polled,
station 3 is the first station polled when polling resumes. Example 4-3
shows how to
specify continuous polling.
Figure 4-3. BISYNC Multipoint Supervisor Continuous Poll Sequence
025CDT .CDD
CALL
OPEN...
CALL
DEFINELIST...
CALL
READ...
Poll-List
Entry 0
Poll-List
Entry 1
Poll-List
Entry pn - 1
EOT
EOT
EOT