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
Envoy Application Programming Manual—427159-001
E-1
E
S-Series Changes to Envoy
The NonStop™ Himalaya S-series server architecture affects I/O processes such as
Envoy because a single data-communications concentrator replaces all former
communications controllers. In addition, the management subsystem that controls the
concentrator required changes to configuration operations. These basic changes mostly
affect SYSGEN configuration and SCF.
NonStop™ Himalaya S-Series Server Architecture
The ServerNet wide area network (SWAN) concentrator on Himalaya S-series servers
replaces the 3602 byte-synchronous and the 3603 asynchronous controllers. Envoy
communicates with the SWAN concentrator to a data link control (DLC) task which runs
in the SWAN concentrator. There are two DLC tasks: WANENVBSC and
WANENVASC. The WANENVBSC DLC task uses the WAN byte driver, emulating the
3602 controller for Himalaya K-series servers, and the WANENVASC DLC task uses
the WAN ASYNC driver, emulating the 3603 controller for Himalaya K-series servers.
The WAN driver provides an interface to the WAN ports on the CLIP (communications
line interface processor). For more information about the SWAN concentrator, refer to
the WAN Subsystem Configuration and Management Manual.
Subsystems running in the NonStop Kernel, such as Envoy, access the SWAN
concentrator through Compaq NonStop™ TCP/IP and the ServerNet LAN Systems
Access (SLSA) subsystems.
The CLIP is the major programmable device within the SWAN concentrator, providing
link-level protocol and a software interface to the server. The CLIP stores and
implements specific communications protocols. There are three CLIPs on one SWAN
concentrator. Each CLIP contains a Motorola MC68EN360 quad integrated
communications controller (QUICC) chip. Each CLIP interfaces to both the A and B
Ethernet ports and has two WAN ports.
G-Series Migration Considerations
This subsection lists the differences between D-series and G-series versions of Envoy.
CBSENSEON and CFSENSEON Modifiers
D-series versions of Envoy
FDX, NAQ read lines do not monitor MODEM signals while a READ is in progress. In
other words, SYSGEN modifiers CBSENSEON and CFSENSEON are not used.
G-series versions of Envoy
CBSENSEON and CFSENSEON are used even for FDX and NAQ lines. In other
words, FDX and NAQ lines also monitor MODEM signals while a READ is in progress.