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1 Introduction
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
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No-protocol Mod
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No-protocol Mode enables you to receive or send data by using serial port output or input instructions.
Data is sent and received by using the SerialSend, SerialRcv, and SerialRcvNoClear instructions. Use
the No-protocol Mode when the data send and receive protocols are created by the user, or when a
Serial Communications Unit is connected to devices that only receive or send data, such as bar code
readers, or printers.
Modbus-RTU Slave Mode enables you to send Modbus-RTU commands from the host computer to
read and write PLC memory used for CJ-series Units.
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No-protocol Mode
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Modbus-RTU Slave Mode
ST
CR+LF
Serial Communications Unit
No-protocol
Text
SerialSend
Execute data transmission
General-purpose external device
Note: Start code and end code can be specified.
Modbus-RTU
Modbus command
Serial Communications Unit