BENSHAW Rsi S Series, Инструкция по эксплуатации

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RS-485 Communication Features
239
Communication Protocol
The built-in RS-485 communication supports Modbu-R TU protocol.
Modbus-RTU Protocol
7.3.1.1 Function Code and Protocol (unit: byte)
In the following section, station ID is the value set at CM.01 (Int485 St ID), and starting address is the
communication address. (starting address size is in bytes). For more information about
communication addresses, refer to 7.4
on page
241
.
Function Code #03: Read Holding Register
Function Code #04: Read Input Register
Query Field Name Response Field Name
Station ID Station ID
Function(0x04) Function (0x04)
Starting Address Hi
Byte Count
Starting Address Lo Data Hi
# of Points Hi Data Lo
# of Points Lo …
CRC Lo …
CRC Hi Data Hi
Data Lo
CRC Lo
CRC Hi
Query Field Name Response Field Name
Station ID Station ID
Function(0x03) Function (0x03)
Starting Address Hi Byte Count
Starting Address Lo Data Hi
# of Points Hi Data Lo
# of Points Lo …
CRC Lo …
CRC Hi Data Hi
Data Lo
CRC Lo
CRC Hi
# number of Points
# number of Points