Lenze DDS v2.0 - Manual (Page 12)

Introduction to IEC 61131-3 programming
General language elements
10
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DDS-IEC61131 EN 2.0
Integers can be defined with a basis, decimal numbers can also have a sign (+ or -). Reals can also
be indicated with exponents.
Identification Example
Integers
decimal
10
binary 2# 2#1010
octal 8# 8#12
hexadecimal 16# 16#A
Reals
without exponent
-12.50
with exponent E 15.7E4
Times
There are two different time literals: Duration and time of day/date.
Identification Example
Duration T# or TIME# T#10ms
Time of day/date
Date
D# or #DATE D#1999-08-29
Time of day TOD# or #TIME_OF_DAY TOD#15:36:30
Date and time of day DT# or #DATE_AND_TIME DT#1999-08-29-15:36:30
4.5 Data types
IEC 61131-3 defines different standard data types. They help to compile derived and user-defined
data types. Each identifier is assigned to a data type. The type determines how much memory is
to be reserved and which values correspond to the memory contents.
Standard data types
•
BOOL (truth values TRUE/FALSE)
•
BYTE , WORD, DWORD, SINT, USINT, INT, UINT, DINT, UDINT (integer data types)
•
REAL (floating point data type)
•
STRING (character string)
•
TIME , TIME_OF_DAY, DATE, DATE_AND_TIME (time data types)
Defined data types:
•
ARRAY (one, two, three-dimensional field)
•
POINTER (contains addresses of variables/function blocks for the run-time of the program)
•
Enumeration ( enumerated, consists of many string constants)
•
STRUCT (structure)
•
Reference (generates an alternative name for a variable/constant/function block)
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