Calculation Of Crc Parity Code - Bell VFM60 Series User Introduction Manual

CRCH ：CRC parity code higher
Note: To read a float date, the quantity of the register address and its value have to be even, or
reponse will be error.
Function code 04 – Same as function code 03
Function code 06 – write one register
Request
01 : Address
06 : Function code
00 : Register address higher
01 : Register address lower (code setting address)
00 : Value higher
04 : Value lower
CRCH ：CRC parity code higher
CRCL : CRC Parity code lower
Note: Function code is only supported for writing short dater.
Function code 16- write multi register.
Request
01 : Address
10H : Function code
00 : Register address higher
01 : Register address lower (digital setting address)
00 : Quantity of register higher
02 : Quantity of register lower
04 : Quantity of values
86h : Value 1
00 : Value 2
00 : Value 3
48H: Value 4
CRCH ：CRC parity code higher
CRCL : CRC Parity code lower
Note: Function code 16 is supported to write both short date and float date. But for float date,the
first register address and the quantity of the registers must be even, or writing is not allowed.

6.3 Calculation of CRC parity code.

Request
01 : Address
10 : Function code
Date:24/04/2020
CRCL : CRC Parity code lower
CRCH ：CRC parity code higher
Response
01: Address
06 : Function code
00 : Register address higher
01 : Register address lower
00 : Value higher
04 : Value lower
CRCH ：CRC parity code higher
CRCL : CRC Parity code lower
Response
01: Address
10H : Function code
00 : Register address higher
01 : Register address lower
00 : Quantity of register higher
02 : Quantity of register lower
CRCH ：CRC parity code higher
CRCL : CRC Parity code lower
Response
N1 CRC=0FFFFH is initial value
N2 XOR operation the CRCL and N1
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