Download Siemens Memory Specifications

Table of contents
Table of contents
Siemens AG 2014 All rights reserved
Warranty and liability................................................................................................... 2
1
Preface ................................................................................................................ 5
2
S7-1200/1500 Innovations ................................................................................. 6
2.1
2.2
2.3
2.4
2.5
2.6
2.6.1
2.6.2
2.6.3
2.6.4
2.6.5
2.7
2.8
2.8.1
2.8.2
2.8.3
2.9
2.9.1
2.9.2
2.9.3
2.10
2.11
2.12
2.13
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Introduction ........................................................................................... 6
Terms ................................................................................................... 6
Programming languages ...................................................................... 8
Optimized machine code ...................................................................... 8
Block creation ....................................................................................... 9
Optimized blocks ................................................................................ 10
S7-1200: Setup of optimized blocks................................................... 10
S7-1500: Setup of optimized blocks................................................... 11
Best possible data storage in the processor on S7-1500 .................. 12
Conversion between optimized and non-optimized tags ................... 15
Communication with optimized data .................................................. 16
Block sizes ......................................................................................... 17
New data types for S7-1200/1500 ...................................................... 17
Elementary data types........................................................................ 17
Date_Time_Long data type ................................................................ 18
VARIANT data type ............................................................................ 18
Instructions ......................................................................................... 20
CALCULATE ...................................................................................... 20
MOVE instructions .............................................................................. 20
RUNTIME ........................................................................................... 21
Symbolic and comments .................................................................... 22
System constants ............................................................................... 23
Internal reference ID for controller and HMI tags ............................... 24
STOP mode in the event of errors ..................................................... 25
General Programming ..................................................................................... 27
3.1
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.2.6
3.2.7
3.2.8
3.3
3.3.1
3.3.2
3.4
3.4.1
3.4.2
3.4.3
3.4.4
3.5
3.6
3.6.1
3.6.2
3.6.3
3.6.4
3.6.5
Operating system and user program .................................................. 27
Program blocks .................................................................................. 27
Organization blocks (OB) ................................................................... 28
Functions (FC) .................................................................................... 30
Function blocks (FB) .......................................................................... 32
Instances ............................................................................................ 33
Multi-instances ................................................................................... 33
Global data blocks (DB) ..................................................................... 35
Downloading without reinitialization ................................................... 36
Reusability of blocks........................................................................... 39
Block interface types .......................................................................... 40
Call-by-value with In interface type .................................................... 40
Call-by-reference with InOut interface type ........................................ 41
Storage concept ................................................................................. 41
Block interfaces as data exchange .................................................... 41
Global memory ................................................................................... 42
Local memory ..................................................................................... 43
Access speed of memory areas ......................................................... 44
Retentivity ........................................................................................... 45
Symbolic addressing .......................................................................... 47
Symbolic instead of absolute addressing ........................................... 47
ARRAY data type and indirect field accesses .................................... 49
STRUCT data type and PLC data types ............................................ 51
Access to I/O areas with PLC data types ........................................... 52
Slice access ....................................................................................... 53
Programming Guideline for S7-1200/1500
Entry-ID: 81318674, V1.2, 03/2014
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