Check Sum - Delta VFD-B User Manual

RTU mode:

3.4 Check sum

ASCII mode:
LRC (Longitudinal Redundancy Check) is calculated by summing up, module 256, the values of
the bytes from ADR1 to last data character then calculating the hexadecimal representation of the
2's-complement negation of the sum.
For example, reading 1 word from address 0401H of the AC drive with address 01H.
01H+03H+04H+01H+00H+01H=0AH, the 2's-complement negation of 0AH is F6H.
RTU mode:
Revision July 2008, BE16, SW V4.08 & V5.00
Command message:
Address
Function
Starting data
address
Number of data
(count by word)
Number of data
(count by byte)
The first data
content
The second data
content
CRC Check Low
CRC Check High
Address 1
Address 0
Function 1
Function 0
Starting data address
Number of data
LRC Check 1
LRC Check 0
END 1
END 0
Address
Function
Starting data address
01H
10H
05H
00H
00H'
02H
04
13H
88H
0FH
A0H
'4D'
'D9'
STX
Chapter 5 Parameters|VFD-B Series
Response message:
Address
Function
Starting data address
Number of data
(count by word)
CRC Check Low
CRC Check High
':'
'0'
'1'
'0'
'3'
'0'
'4'
'0'
'1'
'0'
'0'
'0'
'1'
'F'
'6'
CR
LF
01H
03H
21H
02H
01H
10H
05H
00H
00H
02H
41H
04H
5-89