Omron V680 Series User Manual page 162

Section 7
Host Communications Specifications
 Response Format
 Normal End
Byte 0 Byte 1
Transaction
identifier
Copy of the transaction
identifier that was specified
in the query
Transaction Identifier
A copy of the value that was specified in the query is returned.
Protocol Identifier
This field is always 0000 hex.
Field Length
The number of bytes inclusively from the unit identifier through the end of the data is specified.
Byte 4 will always be 00 hex.
Unit Identifier
This field is always FF hex.
Function code
The value that was specified in the query (Read: 03 hex or Write: 10 hex) is set.
Function code
03 hex
10 hex
Data
The data for the function code is sent.
The format of the data depends on the function code.
The Reader/Writer supports the following data type.
Holding register
RFID System
160
User's Manual
(Modbus TCP)
Byte 2 Byte 3 Byte 4
Protocol identifier
Always
Always 0000 hex
00 hex
Function
Read Holding Register
Write Holding Register
Data name
Read/write 16-bit data
Byte 5 Byte 6 Byte 7
Unit Function
Field length
identifier
No. of Always
bytes FF hex
Range specified with the field length
Description
Byte 8 Byte 9
Data
code
··· Byte n