LXE 1280 Reference Guide
Protocol Messages
213
E-SW-LDSPLUSRG-G
LDS Plus Reference Guide
Protocol Messages
This appendix provides the formats and composition of the protocol messages that are passed
between the asynchronous host computer and the network device.
between the asynchronous host computer and the network device.
A protocol message is a group of characters that defines how the host and network devices
communicate with each other, as opposed to a message that carries data back and forth between
the application program and DOS terminals.
communicate with each other, as opposed to a message that carries data back and forth between
the application program and DOS terminals.
Protocol Message Format
The protocol message format allows the host computer and network device to successfully send
and receive protocol messages. The message format is the same in either direction.
and receive protocol messages. The message format is the same in either direction.
The format for a protocol message is shown below:
SOL ID1 ID2 TYPE
EOL
Figure D-2 Protocol Message Format
Message Characters
This table describes the characters that make up a protocol message:
Protocol
Field
Description
SOL
Start of Line (or start of message) character.
ID1
The first character of a two-character field that identifies the ID of the device that
the message relates to.
the message relates to.
ID2
The second character of a two-character field that identifies the ID of the device
that the message relates to.
that the message relates to.
TYPE
One or two characters that allow the host computer or network device to
determine if the message is a protocol message or a text message being received
from or transmitted to a DOS terminal.
determine if the message is a protocol message or a text message being received
from or transmitted to a DOS terminal.
EOL
End of the Line (or end of message characters).