Omron ZEN - Structure of Command Text; PDU Structure; Addresses; Number of Elements

SECTION 2 CompoWay/F Communications Protocol
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2.2 Structure of Command Text
■ PDU Structure
• An MRC (Main Request Code) and SRC (Sub-Request Code) followed
by the various required data are transferred in the command text.
Service Request PDU
• The MRES (Main Response Code), SRES (Sub-Response Code),
followed by the data are transferred following the above MRC/SRC in
the response frame.
Service Response PDU (Normal Response)
• If the specified command text could not be executed, the service
response PDU will contain only the MRC/SRC and MRES/SRES.
Note: MRES/SRES provides the response code. MRES/SRES is not
output when processing ends in a normal completion.
Service Response PDU (Command Text Not Executed)
■ Addresses
An address is appended to each of the variable types. Express
addresses in 2-byte hexadecimal and append them for the specified
access size.
■ Number of Elements
Specify the number of elements as “0001” (fixed). The number of
elements is expressed in 2-byte hexadecimal.
MRC SRC
Data
MRES SRES MRC SRC
Data
MRES SRES MRC SRC