Lenze PLC Designer PLC Designer (R3-1) - Manual (Page 985)

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Programming Reference
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DMS 4.1 EN 03/2011 TD29 983
16.1.23 Extensible Functions - PARAMS
(not yet implemented)
As an extension to the IEC 61131-3 standard it is possible to declare functions or
methods with a variable number of input parameters of the same type.
Syntax:
<extensible_declaration> : = <function name> : PARAMS OF <data type>
Example:
FUNCTION funHelp : INT
VAR_INPUT
pint : PARAMS OF <base data type>;
END_VAR
Implicitly pint points to a structure containing the components Count of type INT and
Params of type POINTER TO <base data type>.
When calling funHelp it is either possible to pass an array of arbitrary length of type
<base data type>, or a variable number of <base data type>-expressions, or mix both.
Example:
x := funHelp(1, 2, 3);
y := funHelp(intArray);
z := funHelp(1, intArray, 2);
A function may only contain one PARAMS-input, and this input must be the last input
of the function. There is no syntax for explicitly assigning an PARAMS-input within the
function call.
16.1.24 FB_init, FB_reinit Methods
FB_init
The method "FB_init" replaces the INI operator used in »PLC Designer« V2.3. It is a
special method for a function block which can be declared explicitly but also and in any
case is available implicitly. Thus in any case it can be accessed for each function block.
The init method contains initialization code for the function block as declared in the
declaration part of the function block. If the init method is declared explicitly, the
implicit initialization code will be inserted into this method. The programmer can add
further initialization code.
Note: When execution reaches the user defined initialization code, the function
block is already fully initialized via the implicit initialization code.
The init method is called after download all for each declared instance. Attention: In
online change the previous values will overwrite the initialization values!