Control Procedures And Message Formats - Mitsubishi MELSEC Q Series Reference Manual

5.1.2 Control procedures and message formats

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This section illustrates the control procedure and message format of each command
when data communication is performed in each format of the A compatible 1C frames.
The section shown in the message explanation diagram of this section are items
common to all command and corresponds to the
diagrams indicated in sections 5.2.2 and after of this chapter.
Refer to Section 5.1.3 regarding the content and specification method of the data found
in .
POINT
It shows the form 1 to 4 (diagram (1) to (4)) for the QnA compatible 4C frame
shown in this chapter.
(a) When sum check is enabled, the sum check is performed only for the
characters in the areas indicated with ( 1) in the illustrations.
(b) The contents of "Character area A", "Character area B" and "Character area
C" in the diagrams depend on the processing contents. Refer to the
description of each command for more information. The contents of each
character area are the same for all four formats.
(c) When the external device reads data from the programmable controller, the
transmission of messages in the areas marked with ( 2) in the diagram may
be omitted.
(d) When the external device and programmable controller CPU system
configuration is m: n, the control procedure format 3 cannot be used for data
communication.
5 WHEN COMMUNICATING USING THE A COMPATIBLE 1C FRAMES
portion of the message explanation
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