Delta VFD185B43A User Manual

5
VFD-B Series
DELTA ELECTRONICS, INC. ALL RIGHTS RESERVED
5-61
content A0H
CRC Check Low ‘9’
CRC Check High ‘A’
3.4 CHK (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
STX ‘:’
‘0’ ADR 1
ADR 0
‘1’
‘0’ CMD 1
CMD 0
‘3’
‘0’
‘4’
‘0’
Starting register
address
‘1’
‘0’
‘0’
‘0’
Number of data
‘1’
‘F’ LRC CHK 1
LRC CHK 0
‘6’
CR END 1
END 0
LF
01H+03H+04H+01H+00H+01H=0AH,
the 2’s-complement negation of 0AH is F6
H.
RTU mode:
ADR 01H
CMD 03H
21H Starting register
address
02H
00H Number of data
(count by word)
02H
CRC CHK Low 6FH
CRC CHK High F7H
CRC (Cyclical Redundancy Check) is calculated by the following steps:
Step 1: Load a 16-bit register (called CRC register) with FFFFH.
Step 2: Exclusive OR the first 8-bit byte of the command message with the low order
byte of the 16-bit CRC register, putting the result in the CRC register.

Delta VFD185B43A Specifications

General

Brand	Delta
Model	VFD185B43A
Category	DC Drives
Language	English