LG Electronics 120S user manual Command Registration Error code Tail

Chapter 8 Communication Functions

(4) Response Format (NAK response)

Format name	Header	Station No.	Command	Registration	Error code	Tail	Frame check
				No.	(Hex 2Byte)
Frame (Example)	NAK	H10	Y(y)	H09	H1132	ETX	BCC
ASCII value	H15	H3130	H59(79)	H3039	H31313332	H03

Item	Explanation
	When command is lowercase(y), only one lower byte of the value resulted by adding 1 Byte
BCC	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 registered device No. 1 of station No. 1 is read. and BCC value is checked. And it is supposed that device M000 is registered and the number of blocks is 1.

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

Format name	Header	Station No.	Command	Registration No.	Tail	Frame check
Frame (Example)	ENQ	H01	y	H01	EOT	BCC
ASCII value	H05	H3031	H79	H3031	H04

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

Format name	Header	Station No.	Command	Registration	Number of Blocks
				No.
Frame (Example)	ACK	H01	y	H01	H01
ASCII value	H06	H3031	H79	H3031	H3031

Number of

data

H04

H3034

Data	Tail	Frame
		check
H23422339	ETX	BCC
H3233343232	H03
333339

③ For NAK response after execution of command (PC				← MASTER-K120S Main Unit)
Format name	Header	Station No.	Command	Registration No.	Error code	Tail	Frame check
Frame (Example)	NAK	H01	y	H01	Error code (2)	ETX	BCC
ASCII value	H15	H3031	H79	H3031	Error code (4)	H03

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