574
7 APPLICATION INSTRUCTION
7.17 Data operation instruction
CRC calculation
CRC(P)
These instructions calculate the CRC (cyclic redundancy check) value which is an error check method used in
communication. In addition to CRC value, parity check and sum check are available. For obtaining the horizontal parity value
and sum check value, the CCD(P) instruction is available. For the generation of CRC value (CRC-16), these instructions use
"X
16
+ X
15
+ X
2
+ 1" in a polynomial.
■Descriptions, ranges, and data types
■Applicable devices
Ladder diagram Structured text
ENO:=CRC(EN,s,n,d);
ENO:=CRCP(EN,s,n,d);
Operand Description Range Data type Data type (label)
(s) Head device number storing data for which the CRC value is
generated
16-bit unsigned binary ANY16
(d) Device number storing the generated CRC value 16-bit unsigned binary ANY16
(n) Number of 8-bit (1-byte) data for which the CRC value is
generated or the device number storing the number of data
1 to 32767 16-bit unsigned binary ANY16
Operand Bit Word Double word Indirect
specification
Constant Others
X, Y, M, L,
SM, F, B, SB
U\G T, ST,
C, LC
T, ST, C, D,
W, SD, SW, R
U\G Z LC LZ K, H E $
(s)
(d)
(n)
To Next Page
Loading...
Need help?
General
