Dfc_Lrc8 - Delta Standard AX Series Instruction Manual

AX Seri es-St andard I nst ruct i ons Manual

5.1 DFC_LRC8

Supported Products

AX Series

DFC_LRC8: LRC (8-bit) checksum calculation.
FB/FC Instruction
FC DFC_LRC8
Input
•
Name
The start address for
pSrc
The data length for LRC
wLen
*Note 1: The variable type BYTE and WORD can be used for dwLen input.
*Note 2: The memory address given by the pSrc exceeds the usable range,
it may cause controller exceptions, such as %I, %Q and %M.
Output
•
Name
DFC_LRC8
ErrorID
Function
•
After executes the FC instruction, it begins to calculate LRC (8-bit) checksum, starting from the memory address input to pSrc,
while the calculation scope is determined by the input wLen.
Function
LRC calculation.
calculation.
Function
LRC checksum
(Return type)
Error codes
Graphic Expression
Data Type
POINTER TO BYTE
DWORD*
Data Type
BYTE
DL_LRC_ERROR
ST Language
DFC_LRC8(
pSrc:= ,
wLen:= ,
ErrorID=> );
Setting Value
(Default value)
Memory address 1~256 (0)
(0)
Output Range(Default value)
(0)
DL_LRC_ERROR(DFC_NO_ERROR)
Chapt er 5
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