PLC Programming

Appendix C: Data types in CoDeSys
DATE_AND_TIME#1996-05-06-15:36:30
dt#1972-03-29-00:00:00
10.15 Defined data types
ARRAY
One-, two-, and three-dimensional fields (arrays) are supported as elementary data types. Arrays can
be defined both in the declaration part of a POU and in the global variable lists.
Syntax:
:ARRAY [..,..] OF .
ll1, ll2, ll3identify the lower limit of the field range; ul1, ul2 and ul3 identify the upper limit. The range
values must be integers.
Example:
Card_game: ARRAY [1..13, 1..4] OF INT;
Initializing Arrays:
Example for complete initialization of an array:
arr1 : ARRAY [1..5] OF INT := 1,2,3,4,5;
arr2 : ARRAY [1..2,3..4] OF INT := 1,3(7); (* short for 1,7,7,7 *)
arr3 : ARRAY [1..2,2..3,3..4] OF INT := 2(0),4(4),2,3;
(* short for 0,0,4,4,4,4,2,3 *)
Example of the initialization of an array of a structure:
TYPE STRUCT1
STRUCT
p1:int;
p2:int;
p3:dword;
END_STRUCT
ARRAY[1..3] OF STRUCT1:= (p1:=1,p2:=10,p3:=4723),(p1:=2,p2:=0,p3:=299),
(p1:=14,p2:=5,p3:=112);
Example of the partial initialization of an Array:
arr1 : ARRAY [1..10] OF INT := 1,2;
Elements to which no value is pre-assigned are initialized with the default initial value of the basic
type. In the example above, the elements anarray[6] to anarray[10] are therefore initialized with 0.
Array components are accessed in a two-dimensional array using the following syntax:
[Index1,Index2]
Example:
Card_game [9,2]
Note:
If you define a function in your project with the name CheckBounds, you can use it to check for
range overflows in your project (see chapter 'What is what in CoDeSys', 'Components of a project',
'Function')
Function Checkbounds
If you define a function in your project with the name CheckBounds, you can automatically check for
out-of-range errors in arrays. The name of the function is fixed and can only have this designation.
Example for the function CheckBounds:
CoDeSys V2.3 10-33