Hitachi WJ200-001S Instruction Manual page 566

Case 2: When selecting 32-bit parameter for an internal register. (Please refer to the page 1 for setting
range.
Reading Holding Register [03h] , Target register = external register
Query:
No
1 Slave address
2 Function code
3 Register start address (high order)
4 Register start address (low order)
5 Number of holding registers (high order)
6 Number of holding registers (low order)
7 CRC-16 (high order)
8 CRC-16 (low order)
Response:
No Field Name
1 Slave address
2 Function code
3 Exception code
4 CRC-16 (high order)
5 CRC-16 (low order)
Only 16-bit Holding register can be designated as an internal register. So You will get an exception
response if you choose 32-bit register for an internal register.
Field Name
Example
(Hex)
01
83
31
80
E4
Example
(Hex)
01
03
60
Register address value = Register
01
Number - 1
00
One register
01
CB
CA
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