Delta MS300 Series User Manual page 793

Appendix A. Modbus ProtocolMS300
RTU mode:
START
Address
Function
DATA (n-1)
.......
DATA 0
CRC Check Low
CRC Check High
END
Communication address (Address)
2.
00H: broadcast to all AC motor drives
01H: AC motor drive of address 01
0FH: AC motor drive of address 15
10H: AC motor drive of address 16
:
FEH: AC motor drive of address 254
Function (function code) and data (data characters)
3.
03H: read data from a register
Example: Reading two continuous data from register address 2102H, AMD address is 01H.
ASCII mode:
Command Message
STX
Address
Function
Starting register
Number of register
(count by word)
LRC Check
END
Defined by a silent interval of larger than / equal to 3.5 char
Communication address: 8-bit binary address
Command code: 8-bit binary command
Contents of data:
N × 8-bit data, n ≤ 16
CRC checksum:
one 16-bit CRC checksum consists of 2 8-bit binary
characters
Defined by a silent interval of larger than / equal to 3.5 char
':'
'0'
'1'
'0'
'3'
'2' Number of register
'1' (count by byte)
'0'
'2' Content of starting
'0' register 2102H
'0'
'0'
'2'
Content of register 2103H
'D'
'7'
CR
LRC Check
LF
784
Response Message
STX
Address
Function
END
':'
'0'
'1'
'0'
'3'
'0'
'4'
'1'
'7'
'7'
'0'
'0'
'0'
'0'
'0'
'7'
'1'
CR
LF