Omron V680S-HMD63-ETN User Manual page 154

Section 7
Host Communications Specifications
Function Code Descriptions
 Read Holding Register (03 Hex)
This function code is used to read the contents of the specified number of continuous holding registers
starting from the specified address.
 Example: Reading Four Words of Data Starting from Address 1234 Hex in the
RF Tag
Query
No.
1 Transaction identifier upper byte
2 Transaction identifier lower byte
3 Protocol identifier upper byte
4 Protocol identifier lower byte
5 Field length upper byte
6 Field length lower byte
7 Unit identifier
8 Function code
9 Register address upper byte (See note 1.)
10 Register address lower byte (See note 1.)
11 Word count upper byte
12 Word count lower byte
The address in the RF Tag is the same as the register address.
Response
No.
1 Transaction identifier upper byte
2 Transaction identifier lower byte
3 Protocol identifier upper byte
4 Protocol identifier lower byte
5 Field length upper byte
6 Field length lower byte
7 Unit identifier
8 Function code
9 Byte count
10 Read data 1 upper byte
11 Read data 1 lower byte
12 Read data 2 upper byte
13 Read data 2 lower byte
14 Read data 3 upper byte
15 Read data 3 lower byte
16 Read data 4 upper byte
17 Read data 4 lower byte
RFID System
152
User's Manual
(Modbus TCP)
Example
Field name
(hex)
Example
Field name
(hex)
00
00
00
00
00
06
FF
03
12
RF Tag address = Register address
34
00
04
00
00
00
00
00
0B
FF
03
08
11
11
22
22
33
33
44
44