LG Electronics 120S user manual Eot

Chapter 8 Communication Functions

(4) Response format (NAK response)

Format name	Header	Station No.	Command	Command type	Error code	Tail	Frame check
					(Hex 2 Byte)
Ex. of frame	NAK	H10	r	SB	H1132	ETX	BCC
ASCII value	H15	H3130	H72	H5342	H31313332	H03

Item	Explanation
BCC	When command is lowercase(r), only one lower byte of the value resulted by adding 1 Byte
	each to ASCII values from NAK to ETX is converted into ASCII and added to BCC, and sent.
Error code	Hex and 2 bytes(ASCII code, 4 bytes) indicate error type. For the details, see 8.1.8 Error
	codes.

(5) Example

This example supposes that 2 WORDs from M000 of station No. 10 is read and BCC value is checked. Also it is supposed that data in M000 and in M001 is as follow:

M000 = H1234

M001 = H5678

①Computer request format (PC → MASTER-K120S Main Unit)

				Command
Format name	Header	Station No.	Command		Device length	Device name	Number of data	Tail	Frame check
				type
Frame (Example)	ENQ	H0A	r	SB	H06	%MW000	H02	EOT	BCC
ASCII value	H05	H3041	H72	H5342	H3036	H254D5730	H3032	H04
						3030

②For ACK response after execution of command(PC ← MASTER-K120S Main Unit)

Format name	Header	Station No.	Command	Command	Number of	Data	Tail	Frame check
				type	data
Frame (Example)	ACK	H0A	r	SB	H04	12345678	ETX	BCC
ASCII value	H06	H3041	H72	H5342	H3034	H3132333435363738	03

③ For NAK response after execution of command(PC					← MASTER-K120S Main Unit)
Format name	Header	Station No>	Command	Command type	Error code	Tail	BCC
Frame (Example)	NAK	H0A	r	SB	Error code (2Byte)	ETX	BCC
ASCII value	H15	H3041	H72	H5342	Error code (4Byte)	H03

8-14