Liebert OpenComms, Инструкция по установке и эксплуатации

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36 NIC Setup and Testing
RTU Framing Examples
READ REGISTERS (FUNCTION CODE 0X03 &
0X04)
Query: for reading holding /input registers (requested by a client)
Server
Addres
s
Function
Code
(0x3/0x4)
Index of
starting register
Number of
registers to be read
16 bit
CRC
1 byte 1 byte 2 bytes 2 bytes 2
bytes
Response: for reading holding/input registers (response by the server)
Server
Addres
s
Function
Code
(0x3/0x4)
Byte
Count
Data from registers 16 bit
CRC
1 byte 1 byte 1
bytes 2*m bytes (= Byte Count) 2 bytes
WRITE SINGLE HOLDING REGISTER
(FUNCTION CODE 0X06)
Query: for writing a single holding register (requested by a client)
Server
Addres
s
Function
Code
(0x06)
Index of the
register
16 bit value to
be written
16 bit CRC
1 byte 1 byte 2 bytes 2 bytes 2 bytes
Response: for writing a holding registers (response by the server)
Server
Addres
s
Function
Code
(0x06)
Index of the
register
16 bit value
been written
16 bit CRC
1 byte 1 byte 2 bytes 2 bytes 2 bytes