Siemens SINUMERIK 840D sl Function Manual page 1256

Detailed description
2.14 Programming tips with STEP 7
2.14 Programming tips with STEP 7
2.14.1 General
General
Some useful tips on programming complex machining sequences in STEP7 are given below.
This information concentrates mainly on the handling of data type POINTER and ANY.
Detailed information about the structure of data types POINTER and ANY can be found in
Chapter "CPU register and storage of data" in STEP7 manual "Designing user programs".
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
• the routine given below is for smaller data quantities, because the supply of ANY
The following is an example of how to copy data at high speed from one DB into another.
Code
OPEN
LAR1
OPEN
LAR2
L
M001:
L
T
+AR1
+AR2
TAK;
LOOP
272
here a high-speed copying takes place.
parameter to the SFCs consumes additional time.
DB 100;
P#20.0;
DI 101;
P#50.0;
4;
DBW [AR1,P#0.0];
DIW [AR2,P#0.0];
P#2.0;
P#2.0;
M001;
Comment
// DB xx.[AR1] is the source
// DI yy.[AR2] is the destination
//Source DB
//Source start address on data byte 20
//Destination DB
//Destination start address on data byte 50
//AR1, AR2, DB, DI loaded beforehand
//Transfer 8 bytes
//Copy word-oriented
Basic logic functions: PLC Basic program powerline (P3 pl)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0