Diagnostics (Function Diagnostics: 08H) - Mitsubishi Electric MR-JE-C Series Instruction Manual

3. Modbus/TCP
Response Message
Transaction Protocol
Length Field
Identifier Identifier
16 bits 0000h
The following shows the information in each Response Message.
Message field
Transaction Identifier
Protocol Identifier
Length Field
Unit Identifier
Function
Byte Count
Data

3.6.3 Diagnostics (Function diagnostics: 08h)

Use this register when performing the communication check from the client (controller). When a server
(servo amplifier) receives a Query Message, it sends the received data as a Response Message without any
changes to the client (controller).
(1) Message frame
Query Message
Transaction Protocol
Length Field
Identifier Identifier
16 bits 0000h
Message field
Transaction Identifier
Protocol Identifier
Length Field
Unit Identifier
Function
Sub Function
Data
Response Message
Transaction Protocol
Length Field
Identifier Identifier
16 bits 0000h
Message field
Transaction Identifier
Protocol Identifier
Length Field
Unit Identifier
Function
Sub Function
Data
Unit
Function
Identifier
000Bh FFh 03h
Transaction Identifier received from the client (controller) is copied and returned.
The value "0000h" is returned.
The byte length from Unit Identifier to Data is returned.
Unit Identifier received from the client (controller) is copied and returned.
When the message was received without errors, "03h" is returned.
The value "08h" is returned. This means that data of 8 frames is returned.
Data starting from the start address is returned.
Lower-bit value of the register 2B05h: "5678h"
Higher-bit value of the register 2B05h: "1234h"
Value of the register 2B06h: "1000h"
Value of the register 2B07h: "2000h"
Unit
Function
Identifier
0006h FFh 08h
Size
16 bits Set any value.
16 bits Set "0000h".
16 bits Set "0006h".
8 bits Set "FFh".
8 bits Set "08h".
16 bits Set "0000h".
When a value other than "0000h" is set, a communication error occurs.
16 bits Set 2-byte length data.
Unit
Function
Identifier
0006h FFh 08h
Size
16 bits Transaction Identifier received from the client (controller) is copied and returned.
16 bits The value "0000h" is returned.
16 bits The byte length from Unit Identifier to Data is returned.
8 bits Unit Identifier received from the client (controller) is copied and returned.
8 bits When the message was received without errors, "08h" is returned.
16 bits The value "0000h" is returned.
16 bits The data set in the Query Message is returned.
Byte Count
H L
08h 56h 78h
Description
Sub Function
H L H
00h 00h 8 bits
Description
Sub Function
H L H
00h 00h 8 bits
Description
3 - 6
Data
H L H L
12h 34h 10h 00h
Data
L
8 bits
Data
L
8 bits
H L
20h 00h