Expanding the program | Siemens TOA portal module 040-020 instruction

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5.4Expanding the program

Next, we will check whether faulty information is contained in the input parameters of the

'calculate_tankcontent' block. Another value 'high_max' is also passed to the block. This indicates the height of the tank.

The block is now to analyze whether the fill-level of the tank is less than zero or greater than the specified tank height. It is also to be checked whether the diameter was specified as less than zero.

If there is an error, the Boolean output parameter 'er' should return TRUE and the value of the 'Content' parameter should be -1.

Expanding the assignment list / tag table:

Address	Symbol	Data type	Comment
%Q1.7	Error bit	BOOL	Error, unable to perform calculation

Expansion of the interface of the function FC140:				calculate_tankcontent
Type	Symbol	Data type	Comment
IN	high_max	REAL	in meters
OUT	er	REAL	er = 1, there is an error, content = -1

Function call: Representation in FBD

FC140

calculate_tankcontent

Fill level:

REAL

high_max: REAL

Diameter: REAL

BOOL :er

REAL :content

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