Detailed description
2.14 Programming tips with STEP 7
Basic logic functions: PLC basic program solution line (P3 sl)
254 Function Manual, 11/2006, 6FC5397-0BP10-2BA0
2.14.2 Copying data
For the high-speed copying of data from one DB into another it is recommended
• for larger data quantities to use the system function SFC BLKMOV or SFC FILL, because
here a high-speed copying takes place.
• the routine given below is for smaller data quantities, because the supply of ANY
parameter to the SFCs consumes additional time.
The following is an example of how to copy data at high speed from one DB into another.
Code Comment
// DB xx.[AR1] is the source
// DI yy.[AR2] is the destination
OPEN DB 100; //Source DB
LAR1 P#20.0; //Source start address on data byte 20
OPEN DI 101; //Destination DB
LAR2 P#50.0; //Destination start address on data byte 50
//AR1, AR2, DB, DI loaded beforehand
L 4; //Transfer 8 bytes
M001:
L DBW [AR1,P#0.0]; //Copy word-oriented
T DIW [AR2,P#0.0];
+AR1 P#2.0;
+AR2 P#2.0;
TAK;
LOOP M001;
2.14.3 ANY and POINTER
2.14.3.1 General
General
The following programming examples illustrate different programming mechanisms. They
demonstrate how input/output and transit variables (VAR_INPUT, VAR_OUTPUT,
VAR_IN_OUT) are accessed by data types "POINTER" or "ANY" within an FC or FB. The
access operations are described in such a way that a part symbolic method of programming
can be used.
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