General Information
1.13 CRC Calculation (CHECKSUM for RTU)
ATC5300
14
Modbus Communication Protocol, Edition 03/2011, A5E02469001-02
1.13
CRC Calculation (CHECKSUM for RTU)
CRC Calculation Workflow
XOR
= exclusive or
n
= number of information bits
POLY
= calculation polynomial of the CRC 16 = 1010 0000 0000 0001
(Generating polynomial = 1 + x
2
+ x
15
+ x
16
)
In the CRC 16, the 1
st
byte transmitted is the least significant one.
CRC x or B Y TE = CRC
n = 0
CRC right s hift
carry over
CRC x or PO LY = CRC
n = n + 1
nex t B YTE
end mes sage
E nd
n > 7
H ex FFFF = CRC
n o
no
ye s
yes
