DECODE EMU-C3 User Manual - Page 9

Browse online or download pdf User Manual for Measuring Instruments DECODE EMU-C3. DECODE EMU-C3 15 pages. Electricity measurement units

EMU - User manual v1.2
5

Modbus communication

The Decode EMU device supports the Modbus RTU protocol on the RS-485 port. Supported
serial speeds are 1200, 2400, 4800, 9600, 19200, 57600 and 115200 bits per second.
Supported formats are 8 bit and No Parity, Even Parity or Odd Parity.
Device support two modbus functions: 03 - Read holding register and 06 - Preset single
register which may be used only in SETUP mode.

5.1 Supported functions

5.1.1

Function 03 - Read Holding Register

The query consists of 8 bytes. Make sure that only existing registers can be read.
Byte
Field name
1
Device address
2
Function
3
Register address Hi
4
Register address Low
5
Register number Hi
6
Register number Low
7
CRC error check Lo
8
CRC error check Hi
The response consists of n + 5 bytes, n is from 2 to 34, so the length is from 7 to 39 bytes:
Byte
Field name
1
Device address
2
Function
3
Bytes number
4
Register Hi
5
Register Low
...
...
n+4
CRC error check Lo
n+5
CRC error check Hi
www.decode.rs
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Content
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Modbus communication
EMU_UM_V12_05042020.pdf