Modbus Tcp; Header Format; Setting Of Unit Id; List Of Modbus Functions Supported - Toshiba TOSVERT VF-S15 Function Manual

8.

Modbus TCP

8.1. Header format

Byte Description
0 Transaction
1 identifier
2
Protocol
3 identifier
4
Length of data
5
6 Unit ID (Destination identifier)
7 Modbus request function code Chose from Function code described in Section 8.3.

8.2. Setting of Unit ID

The Unit ID (destination identifier) is used to access inverter Modbus TCP servers:
Unit ID
0-248
251

8.3. List of Modbus functions supported

Function code
03 (0x03)
06 (0x06)
16 (0x10)
43 (0x2B)
high order Same transaction ID is returned from Modbus TCP server.
low order Fixed at 0 if it is not required.
high order
This identifier always equals 0.
low order
high order Number of bytes after the Unit ID (Byte 6). The value of the high
order should be "0", because the frame length is always less
low order
than 256 bytes.
Chose from Unit ID described in Section 8.2.
Modbus TCP server
Inverter (VF-S15/AS3/MB1)
Communication module
(this product)
Function name
Read Holding Register
Write Single Register
Write Multiple Registers
Read Device Identification
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Comments
Accessible data
Inverter parameter
Device identification of inverter
Device identifications of module
Description
Read N output words
Write one output word
Write N output words
Identification
E6582051
Size of data
63 words max.
-
63 words max.
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