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
Application Programming With Envoy
Envoy Application Programming Manual—427159-001
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Envoy Subsystem Architecture
Envoy Subsystem Architecture
An Envoy subsystem consists of the following:
•
Envoy I/O communications module
•
Protocol and driver modules
•
Physical line
The I/O communications process serves as the interface to the file-system and
management applications for the different communications lines. The driver process
handles the physical I/O for the asynchronous and synchronous lines while the protocol
process handles the logic for the different types of protocols, such as message formatting
and flow control.
Figure 1-2
shows the architecture of the Envoy subsystem and the relationship of its
components.
Figure 1-2. Envoy Subsystem Architecture
004CDT .CDD
Applications
Envoy I/O Communication Process
DriversProtocols
ASYNCBISYNCASYNC BISYNC
BISYNC
ASYNC
TINET
Burroughs
SIMPLEX
FDX
SWIFT
ADM2
Burroughs
ADM2
ASYNC
BISYNC
FDX
Physical Line