Jaden DLB1-0004T4G, Инструкция по эксплуатации

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received, each device decodes to determine whether it is sending to themselves. After the
last transmitted characters, a pause of at least 3.5-character time marks ending the
message. A new message can start after this pause.
Whole message must be transmitted as a continuous stream. If there is apause time
over 1.5 a character before completion, receiver will refresh and assumes that next byte is
address domain of a new message. Also, if a new message starts within a time interval of
less than 3.5 character after previous message, receiver will regard the new message
ascontinuation of previous message. This will led to an error, because at last the CRC
domain value will be wrong.
RTU frame format:
Frame START At least 3.5 character time
Slave address ADR Communication address:0~247
Command code CMD 03:Read slave parameter ; 06:Write slave parameter
Data content DATA(N-1)
Information:function code parameter address, function code
parameter quantity, function code parameter value etc.
Data content DATA(N-2)
………………………
Data content DATA0
CRC CHK High place
detection value:CRC value
CRC CHK Low place
END
At least 3.5 character time
CMD(command instruction) and DATA(description).
Command code:03H, read N words (max 12 words)
For example:Slave address is 01, start address is P0.02, continously read 2 value.
Master command information
ADR 01H
CMD 03H
Start address high place
F0H
Start address low place
02H
Registar number high place
00H
Registar number low place
02H
CRC CHK low place
CRC CHK value
CRC CHK high place
Slave response information