Mitsubishi Electric MELSEC-L SERIES Basic User Manual page 140

(2) No procedure
In the application data for communications in the "No Procedure" control method, the following data code is
expressed in a binary code. Communications are performed using a binary code regardless of the
communication data code setting.
In communications in the "No Procedure" control method, a subheader or data length setting is not added unlike the
"Procedure Exist" control method; therefore, all data are handled as a valid text. In addition, the E71 turns on Fixed buffer
reception status signal after storing the size of the received message (packet) in the data length storage area. It is
recommended to set a checking method. For example, include data length and a data type code in the application data of a
message so that the number of bytes and data type of the application data can be identified on the receiving side.
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Text (command)
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