Function Code - Fuji Electric ZPA Instruction Manual

5.4

Function code

According to MODBUS protocol, register numbers are assigned by function codes.
Each function code acts on specific register number.
This correspondence is shown in Table 5-2, and the message length by function is shown in Table 5-3.
Table 5-2 Correspondence between function codes and objective address
No. Function
03 Read-out
H
(continuously)
04 Read-out
H
(continuously)
06 Write-in
H
Write-in
10
H
(continuously)
Function
code
03 Read-out of word data
H
04 Read-out of word data
H
(read-out only)
06 Write-in of word data
H
10 Write-in of continuous word data
H
INZ-TN5A1190-E
Function code
Object
Holding register
Input register
Holding register
Holding register
Table 5-3 Function code and message length
Contents
No.
4xxxx Read-out/write-in
3xxxx Read-out word data
4xxxx Read-out/write-in
4xxxx Read-out/write-in
Number of Command message
designatable
Minimum Maximum Minimum Maximum
data
64 words 8
64 words 8
1 word 8
64 words 11
Resister No.
Contents
word data
word data
word data
[Unit : byte]
Response message
8 7
8 7
8 8
137 8
133
133
8
8
11