YASKAWA P1000, Техническое руководство

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The example in Table C.4 shows the CRC-16 calculation of the slave address 02H and the function code 03H, yielding the
result D140H.
Note: This example does not show the calculation for a complete MEMOBUS/Modbus command. Normally data would follow in the calculation.
Table C.4 CRC-16 Checksum Calculation Example
Description Calculation Overflow Description Calculation Overflow
Initial Value (FFFFH) 1111 1111 1111 1111 Function Code 03H 0000 0000 0000 0011
Address 02H 0000 0000 0000 0010 XOR w result 1000 0001 0011 1101
XOR w initial value 1111 1111 1111 1101 Shift 1 0100 0000 1001 1110 1
Shift 1 0111 1111 1111 1110 1 XOR w A001H 1010 0000 0000 0001
XOR w A001H 1010 0000 0000 0001 XOR result 1110 0000 1001 1111
XOR result 1101 1111 1111 1111 Shift 2 0111 0000 0100 1111 1
Shift 2 0110 1111 1111 1111 1 XOR w A001H 1010 0000 0000 0001
XOR w A001H 1010 0000 0000 0001 XOR result 1101 0000 0100 1110
XOR result 1100 1111 1111 1110 Shift 3 0110 1000 0010 0111 0
Shift 3 0110 0111 1111 1111 0 Shift 4 0011 0100 0001 0011 1
Shift 4 0011 0011 1111 1111 1 XOR w A001H 1010 0000 0000 0001
XOR w A001H 1010 0000 0000 0001 XOR result 1001 0100 0001 0010
XOR result 1001 0011 1111 1110 Shift 5 0100 1010 0000 1001 0
Shift 5 0100 1001 1111 1111 0 Shift 6 0010 0101 0000 0100 1
Shift 6 0010 0100 1111 1111 1 XOR w A001H 1010 0000 0000 0001
XOR w A001H 1010 0000 0000 0001 XOR result 1000 0101 0000 0101
XOR result 1000 0100 1111 1110 Shift 7 0100 0010 1000 0010 1
Shift 7 0100 0010 0111 1111 0 XOR w A001H 1010 0000 0000 0001
Shift 8 0010 0001 0011 1111 1 XOR result 1110 0010 1000 0011
XOR w A001H 1010 0000 0000 0001 Shift 8 0111 0001 0100 0001 1
XOR result 1000 0001 0011 1110 XOR w A001H 1010 0000 0000 0001
Perform operations with next data (function code)
XOR result 1101 0001 0100 0000
CRC-16
1101 0001 0100 0000
D 1 4 0
(Lower) (Upper)
Continue from here with next data.
n Response Data
Perform a CRC-16 calculation on the response message data as described above as a validation check. The result should match
the CRC-16 checksum received within the response message.
C.7 Message Format
YASKAWA SIEP YAIP1U 01C AC Drive - P1000 Technical Manual 517
C
MEMOBUS/Modbus Communications