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
4-2
Application Process Interface
Application Process Interface
An application process acting as a centralized station in a multipoint network interfaces
with Envoy and the tributary stations by way of Guardian 90 file-system procedure calls.
This subsection includes:
•
Opening a Line on page 4-2
•
Poll and Select Addresses on page 4-2
•
Polling on page 4-3
•
ASCII and EBCDIC Line Code on page 4-5
•
Retries on page 4-5
•
Timeouts on page 4-6
•
Limited Conversational Mode on page 4-7
Opening a Line
Before it can transmit or receive data, the application process must first open a
communication line. BISYNC multipoint lines are always opened for exclusive read-
write access. The backup process of the application process can also open the line.
Poll and Select Addresses
An application process acting as a multipoint supervisor station must provide an address
list to Envoy. The address list consists of two addresses: the poll address of any stations
that are to be polled and the select address of each station. The application process
passes the address list to Envoy by calling the DEFINELIST procedure. The format of
the address list is described under Address-List Format on page 4-10.
Table 4-1. BISYNC Multipoint Supervisor Formats
BISYNC Multipoint Supervisor Format
heading SOH-head-ETB BCC
heading-text SOH-head-STX-text-ETB|ETX BCC
text STX-text-ETB|ETX BCC
transparent text DLE STX-text-ETB|ETX BCC
or
SOH-head-DLE STX-text-ETB|ETX BCC
intermediate blocked text STX-text-ITB BCC-text-ETX BCC
or
DLE STX-text-ITB BCC-text-ETX BCC