Check Sum - Delta Electronics AC Motor Drive VFD-EL User Manual

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.
Revision August 2008, 2ELE, V1.02
Data content
CRC CHK Low
CRC CHK 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
17H
70H
86H
22H
STX
Chapter 4 Parameters|
Data content
CRC CHK Low
CRC CHK High
':'
'0'
'1'
'0'
'3'
'0'
'4'
'0'
'1'
'0'
'0'
'0'
'1'
'F'
'6'
CR
LF
17H
70H
86H
22H
4-91