LG Electronics 120S user manual Communication Functions Frame Structure, Base Format

Chapter 8 Communication Functions

8.1.3 Frame Structure

1)Base Format

(1)Request frame(external communication device → MASTER-K120S main unit), (Max. 256 Bytes)

Header

(ENQ)

Station number

Command

Command type

Structurized data area

Tail

(EOT)

Frame check

(BCC)

(2)ACK Response frame (MASTER-K120S main unit → external communication device, when receiving data normally) (max. 256 Bytes)

Header

(ACK)

Station number

Command

Command

type

Structurized data area or null code

Tail

(ETX)

Frame check

(BCC)

(3) NAK Response frame (MASTER-K120S main unit → external communication device,

when receiving data abnormally) (max. 256 Bytes)

Header

(NAK)

Station number

Command

Command type

Error code (ASCII 4 Byte)

Tail

(ETX)

Frame check

(BCC)

Remark

1)Used control codes are as follows. Be familiar with the following control codes. Because they are importantly used for communication.

Codes	Hex value	Name	Contents
ENQ	H05	Enquire	Request frame initial code
ACK	H06	Acknowledge	ACK response frame initial code
NAK	H15	Not Acknowledge	NAK response frame initial code
EOT	H04	End of Text	Request frame ending ASCII code
ETX	H03	End Text	Response frame ending ASCII code

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