Type checking

At compile time, the PE Scheduler checks type compatibility as far as is possible. This process catches some errors, such as trying to add a number to a character string.

However, not all type compatibility errors can be detected at compile time. The expression

'sinusoid' / 2.0

works well if sinusoid has a numeric value. However, if sinusoid is equal to the digital state Shutdown the expression returns an error (Calc Failed).

Note: Comparisons (expressions using relational operators) are an exception to this rule. Every comparison is valid, regardless of its operand types.