LG Electronics 120S user manual Remark

Chapter 8 Communication Functions

•S3 format is as below.

bit 15		bit 8		bit 1		bit 0
	Error code		Error bit		NDR bit

•NDR : when the communication ends normally, this bit turns on during 1 scan.

•Error bit : when communication error occurs, this bit turns on during 1 scan. At that time error code stores bit 8 ~ bit 15.

•Error code is as follow

Code	Error type		Meaning
01	Illegal Function		Error in inputting function code in instruction.
02	Illegal Address		Error of exceeding the area limit of reading/writing on the slave station.
03	Illegal Data Value		Error when the data value to be read from or write on the slave station isn’t
			allowed.
04	Slave Device Failure		Error status of the slave station.
			It’s a responding code of the slave station for the master station to prevent the
05	Acknowledge		master station time-out error, when request command processing takes time.
			The master station marks an error code and waits for a certain time without
			making any second request.
06	Slave Device Busy		Error when request command processing takes too much time. The master
			should request again.
07	Time Out		Error when exceeds the time limit of the communication parameter as it
			communicates.
08	Number Error	Errors when data is 0 or more than 256 bytes
09	Parameter Error	Error of setting parameters (mode, master/ slave)
10	Station Error		Error when the station number of itself and the station number set by the
			S1 of instruction are the same.
Remark

-. In MASTER-K120S series, the ‘MODBUS’ command which has been used in MK80S series can be used. In this case, communication channel is fixed to channel 0.

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