Delta DVP-ES2/EX2/SS2/SA2/SX2/SE manual Communication Protocol Ascii mode, END1, END0

4 . Communications

−7 data bits

−1 stop bit

−Even parity

−Baud rate: 9600

4.2Communication Protocol ASCII mode

Communication Data Structure

9600 (Baud rate), 7 (data bits), Even (Parity), 1 (Start bit), 1 (Stop bit)

Field name	Content
Start bit	STX
Communication	ADR 1
address	ADR 0
Command code	CMD 1
	CMD 0
	DATA (0)
Data	DATA (1)
	……….
	DATA (n-1)
LRC checksum	LRC CHK 1
	LRC CHK 0
Stop bit	END1
	END0

Explanation

Start bit ‘:’ (3AH)

Address consists of 2 ASCII codes

Command code consists of 2 ASCII codes

Data content consist of 2n ASCII codes, n≤205

LRC checksum consists of 2 ASCII codes

Stop bit consists of 2 ASCII codes END1 = CR (0DH),

END0 = LF (0AH)

Corresponding table for Hexadecimal value and ASCII codes

ASCII	“0“	“1“	“2“	“3“	“4“	“5“	“6“	“7“
Hex	30H	31H	32H	33H	34H	35H	36H	37H
ASCII	“8“	“9“	“A“	“B“	“C“	“D“	“E“	“F“
Hex	38H	39H	41H	42H	43H	44H	45H	46H

4.2.1 ADR (Communication Address)

Valid communication addresses are in the range of 0~254. Communication address equals to 0 means broadcast to all PLCs. PLC will not respond to a broadcast message. PLC will reply a normal message to the master device when communication address is not 0.

Example, ASCII codes for communication address 16 in Decimal. (16 in Decimal = 10 in Hex) (ADR 1, ADR 0)=’1’,’0’Ö’1’=31H, ‘0’ = 30H

4.2.2 CMD (Command code) and DATA

The content of access data depends on the command code.

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