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1 Introduction
1-34
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
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No-protocol Mode
Creating the User Program
Execute the SerialSend instruction to send the program to the external device from the Controller.
For the SerialSend instruction, include an N.O. of the Network Communications Instruction Enabled
Flag (_Port_isAvailable) and an N.C. of the SerialSend Executing Flag
(*_P1_NopSerialSendExecSta/*_P2_NopSerialSendExecSta) in an AND condition as the input con-
dition.
Execute the SerialRcv or SerialRcvNoClear instruction to receive data at the Controller from the
external device.
Include an N.O. input for the Reception Completed Flag (*_P1_NopRcvCompleteSta or
*_P2_NopRcvCompleteSta) and an N.O. input of the Network Communications Instruction Enabled
Flag (_Port_isAvailable) in an AND condition as the input condition to the SerialRcv or SerialRcvNo-
Clear instruction.
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Modbus-RTU Slave Mode
Modbus-RTU commands are sent from the host computer to the controller.
The host computer must be programmed to send the Modbus-RTU commands and receive
responses.
Programming to
send commands
and receive
responses.
Host computer
Command
Serial Communications Unit