Athena 16C series, Руководство пользователя

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14
Protocol (Standard)
Communications
Option Menu
Protocol
The Protocol provides an easy way to query and
modify controller parameters using a personal computer and the
optional digital communications option of the 16C.
In this manual, the word “host” refers to the personal computer
that’s communicating with the controllers in the serial link, and the
word “slave” refers to the controllers themselves.
All transactions between the host and the slaves are done with
messages consisting of only printable ASCII characters. There are
only two primary types of messages: Requests
and Responses. Messages coming from the host are called
requests and messages coming from the slaves are called
responses.
With the exception of a broadcast request, for every request sent
from the host, the slave will send back a response. If a slave does
not respond within 100 milliseconds, then the request can be con-
sidered lost.
A broadcast request is a request having an ID of ‘00’ (see Message
Formats on next page). It is used to address all slaves on the net-
work. All slaves on the network will perform the actions requested
in a broadcast message. However, a response message will not be
returned. Therefore, the host can only broadcast Write or Auxiliary
Command Requests. All slaves will ignore all Read Broadcast
Requests.
Digital
Communications
Option