Data content

17H

 

70H

 

 

 

CRC CHK Low

86H

 

 

CRC CHK High

22H

 

 

3.4 Check sum

ASCII mode:

Chapter 4 Parameters

Data content

17H

 

70H

 

 

 

CRC CHK Low

86H

 

 

CRC CHK High

22H

 

 

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.

STX

Address 1

Address 0

Function 1

Function 0

Starting data address

Number of data

LRC Check 1

LRC Check 0

END 1

END 0

‘:’

‘0’

‘1’

‘0’

‘3’

‘0’

‘4’

‘0’

‘1’

‘0’

‘0’

‘0’

‘1’

‘F’

‘6’

CR

LF

01H+03H+04H+01H+00H+01H=0AH, the 2’s-complement negation of 0AH is F6H.

Revision August 2008, 2ELE, V1.02

4-91

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Image 134
Delta Electronics VFD-EL manual Data content 17H 70H