Example¶

Example¶
MODBUS interface of the client	COM1
Client reads from	Server 1
Data	%MW0.8196 = 4; %MW0.8197 = 5; %MW0.8198 = 6
Source address at server	%MW0.8196 : 2004HEX = 8196DEC
Target address at client	awReadWord : ARRAY[0..2] OF WORD;
The values of the flag words %MW0.8196..%MW0.8198 on the server are written to the ARRAY awReadWord on the client.

MODBUS request of the client¶
Server address	Function code	Server operand address		Number of words		CRC
Server address	Function code	High	Low	High	Low	High	Low
01HEX	03HEX	20HEX	04HEX	00HEX	03HEX	4FHEX	CAHEX

MODBUS response of the server¶
Server address	Function code	Number of bytes	Data	Data	Data	CRC
Server address	Function code	Number of bytes	High / Low	High / Low	High / Low	High	Low
01HEX	03HEX	06HEX	00HEX /04HEX	00HEX /05HEX	00HEX /06HEX	40HEX	B6HEX

Parameterization \ of the COM_MOD_MAST Function Block inputs¶
EN	COM	SLAVE	FCT	TIMEOUT	ADDR	Number of words	DATA
FALSE -> TRUE	1	1	3	Application- specific	8196	3	ADR (awReadWord[0])