Shenzhen Hpmont Technology Co., Ltd.
Appendix B Communication Protocol
HD3N Series User Manual V1.1
- 145 -
3.
Protocol Function
Supported function
MODBUS protocol supports the below parameter operation:
Supported function
Code
Instructions
To read function parameters and status
parameter
0x03
To rewrite single function parameter or
control parameter
0x06
Set by F17.09
0x41
Not saved at power off
To rewrite numbers of function
parameters or control parameters
0x10
Set by F17.09
0x43
Saved at power off
To read function parameters and status parameter
Function code 0x03, command Frame and response Frame are in below table (Take RTU as an
example).
Command
Frame
Address
Code
Starting register
address
No. of register
CRC/LRC
checking
Data Frame
bytes
1
1
2
2
2/1
Value or range
0 - 247
0x03
0x0000 - 0xFFFF
0x0001 - 0x000C
Response
Frame
Address
Code
Read byte no.
Register content
CRC/LRC
checking
Data Frame
bytes
1
1
1
2* no. of registers 2/1
Value or range
1 - 247
0x03
2* no. of registers
To rewrite single function parameter or control parameter
Function code 0x06 (set by F17.09), 0x41 (Not saved at power off); command Frame and response
Frame are in below table (Take RTU as an example).
。
Command
Frame
Address
Code
Register address
Register content
CRC/LRC
checking
Data Frame
bytes
1
1
2
2
2/1
Value or range
0 - 247
0x06, 0x41
0x0000 - 0xFFFF
0x0000 - 0xFFFF
Response
Frame
Address
Code
Register address
Register content
CRC/LRC
checking
Data Frame
bytes
1
1
2
2
2/1
Value or range
1 - 247
0x06, 0x41
0x0000 - 0xFFFF
0x0000 - 0xFFFF
B