Siemens SINUMERIK 828D Turning, Руководство по эксплуатации функций

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P3: Basic PLC Program for SINUMERIK 840D sl
13.15 Programming tips with STEP 7
Basic Functions
1078
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
13.15.2.2 Use of POINTER and ANY in FB
Function
FB 99 has inputs parameters that are defined as POINTER or ANY.
The example shows a body program via which the subcomponents of the POINTER or ANY can be accessed. In
this case, the DB parameterized with POINTER or ANY is opened and the address offset stored as a cross­area
pointer in address register AR1, thus allowing access to data elements of variables (generally structures and
arrays) that are addressed via the POINTER, ANY.
This access operation is described at the end of the relevant program sequence in the example. With data type
ANY, it is also possible to execute a check or branch when the variable is accessed based on the data type and
the number of elements involved.
Example
T #typ;
L W [AR1,P#2.0]; //Retrieve amount
T #Amount;
L W [AR1,P#4.0]; //Retrieve DB number
T #dbchr;
L D [AR1,P#6.0]; //Offset part of pointer
LAR1 ;
OPEN DB [#dbchr]; //Open DB of variables
L B [AR1,P#0.0]; //Retrieve byte value using ANY
Code Comment
FUNCTIONBLOCK FB 99
VAR_INPUT
Row : BYTE ;
Convert : BOOL ; //Activate numerical conversion
Addr: POINTER; //Points to variable
Addr1 : ANY ;
END_VAR
VAR_TEMP
dbchr : WORD ;
Number: WORD ;
type : BYTE ;
END_VAR
BEGIN
NETWORK
TITLE =
//POINTER
L P##Addr;
Code Comment