Delta PG-40 Specifications download pdf (Page 96)

VFD-B Series

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’

Number of data

‘1’

‘F’ LRC CHK 1

LRC CHK 0

‘6’

CR END 1

END 0

01H+03H+04H+01H+00H+01H=0AH,

the 2’s-complement negation of 0AH is F6

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.

1 2 ... 91 92 93 94 95 96 97 98 99 100 101 ... 178 179

Comments to this Manuals

No comments

Delta PG-40 Specifications Page 96

Comments to this Manuals

Related products and manuals for Water heaters & boilers Delta PG-40