Detailed description
2.14 Programming tips with STEP 7
Basic logic functions: PLC Basic program powerline (P3 pl)
278
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
FUNCTIONBLOCK FB 99
Comment
T
#typ;
L
DIW [AR1,P#2.0];
//Retrieve amount
T
#Amount;
L
DIW [AR1,P#4.0];
//Retrieve DB number
T
#dbchr;
L
DID [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
2.14.4
Multiinstance DB
With version 7 and higher of STEP 7, FBs might have a multiinstance capability, i.e., they
might incorporate multiinstance DBs. The primary characteristic of multiinstance DBs is that
a block can be used for various instances of FBs (see STEP 7 documentation). As such, the
quantity structure of the DBs can be optimized.
Multi-instance DBs should be activated only when they are actually going to be used since
they increase the runtime and code size of the FBs.
Note
When complex programs are implemented in multiinstance FBs that use a pointer and
address register, it is important for the programmer to observe certain rules.
With multiinstance DBs, the start address of the variable (VAR_INPUT, VAR_OUTPUT,
VAR_IN_OUT, VAR) is transferred with the DI data block register and address register AR2.
When variables are accessed within the multiinstance FB, the compiler independently
controls the access operation via address register AR2. However, when complex program
sections also have to work with address registers in the same FB (e.g., to copy data), then
the old contents of AR2 must be saved before the register is changed. The contents of AR2
must be restored to their original state before an instance variable (VAR_INPUT,
VAR_OUTPUT, VAR_IN_OUT, VAR) is accessed. The AR2 register of the instance is to be
saved most usefully in a local variable (VAR_TEMP).
The command "Load pointer to an instance variable" returns a pointer value from the start of
the instance data. To be able to access this variable via a pointer, the offset stored in AR2
must be added.
Содержание SINUMERIK 840D sl
Страница 282: ...Index Basic logic functions Acceleration B2 64 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 286: ...Table of contents Basic logic functions Diagnostic tools D1 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 328: ...Constraints Basic logic functions Diagnostic tools D1 46 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 330: ...Examples Basic logic functions Diagnostic tools D1 48 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 340: ...Table of contents Basic logic functions Travel to fixed stop F1 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 342: ...Brief Description Basic logic functions Travel to fixed stop F1 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 382: ...Supplementary conditions Basic logic functions Travel to fixed stop F1 46 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 388: ...Basic logic functions Travel to fixed stop F1 Function Manual 11 2006 6FC5397 0BP10 2BA0 52 ...
Страница 790: ...Table of contents Basic logic functions Axes coordinate systems frames K2 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 946: ...Table of contents Basic logic functions Emergency Stop N2 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 948: ...Brief Description Basic logic functions Emergency Stop N2 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 956: ...Restrictions Basic logic functions Emergency Stop N2 14 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 958: ...Examples Basic logic functions Emergency Stop N2 16 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 962: ...Index Basic logic functions Emergency Stop N2 20 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 966: ...Table of contents Basic logic functions Transverse axes P1 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 978: ...Supplementary conditions Basic logic functions Transverse axes P1 16 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 980: ...Examples Basic logic functions Transverse axes P1 18 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 982: ...Data lists 5 1 Machine data Basic logic functions Transverse axes P1 20 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 984: ...Index Basic logic functions Transverse axes P1 22 Function Manual 11 2006 6FC5397 0BP10 2BA0 Work offset external 13 ...
Страница 990: ...Table of contents Basic logic functions PLC Basic program powerline P3 pl 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1268: ...Supplementary conditions Basic logic functions PLC Basic program powerline P3 pl 284 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1270: ...Examples Basic logic functions PLC Basic program powerline P3 pl 286 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1280: ...Table of contents Basic logic functions PLC basic program solution line P3 sl 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1542: ...Examples Basic logic functions PLC basic program solution line P3 sl 268 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1604: ...Examples Basic logic functions Reference Point Approach R1 58 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1616: ...Brief Description Basic logic functions Spindles S1 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1703: ...Basic logic functions Spindles S1 Function Manual 11 2006 6FC5397 0BP10 2BA0 93 Constraints 3 No supplementary conditions apply ...
Страница 1704: ...Constraints Basic logic functions Spindles S1 94 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1716: ...Index Basic logic functions Spindles S1 106 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1776: ...Detailed description 2 3 Feedrate control Basic logic functions Feeds V1 60 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1786: ...Data lists 5 3 Signals Basic logic functions Feeds V1 70 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1794: ...Table of contents Basic logic functions Tool Offset W1 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1798: ...Short description Basic logic functions Tool Offset W1 10 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1992: ...Data lists 5 3 Signals Basic logic functions Tool Offset W1 204 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 1996: ...Index Basic logic functions Tool Offset W1 208 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 2002: ...Brief description Basic logic functions NC PLC interface signals Z1 6 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 2150: ...Table of contents Basic logic functions Appendix 4 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...
Страница 2184: ...Glossary Basic logic functions Appendix 38 Function Manual 11 2006 6FC5397 0BP10 2BA0 ...