Envoy Application Programming Manual

Envoy Application Programming Manual—427159-001
9-1
9
Burroughs Point-To-Point Protocol
The Burroughs point-to-point protocol enables an application process to act as a station
in a Burroughs dedicated point-to-point contention network.
Topics discussed in this section include:
•
Protocol Capabilities on page 9-1
•
Application Process Interface on page 9-2
•
File-System Procedures on page 9-3
•
Message Formats on page 9-5
•
File-System Errors on page 9-7
•
Line Action by Procedure Call on page 9-9
Protocol Capabilities
This protocol allows for an application process to communicate in contention mode with
a Burroughs or Compaq system over an asynchronous or a byte-synchronous line. The
protocol is described in the manual, Burroughs Data Communicator #24, revision 1,
published by Burroughs.
In contention mode, neither station has total control of the line. A station with data to
send must first become the master by sending a line bid (ENQ) and receiving a positive
response (ACK) from the other station.
•
The protocol includes the following capabilities:
•
Check-character generation and verification
•
Retries of operations in error
•
Timeouts on all line operations
•
Support for the message formats shown in Table 9-1.
Table 9-1. Burroughs Point-to-Point Protocol Formats
Burroughs Point-to-Point Format
heading-text SOH-heading-STX-text-ETB|ETX BCC
text STX-text-ETB|ETX BCC