Detects comparison operations on variables of type BOOL
Justification: CODESYS permits these kinds of comparison, but they are very unusual and can be confusing. The IEC 61131-3 standard does not provide for these comparisons. By avoiding them, you increase the portability of the code to other development systems.
Importance: Medium
Example
PROGRAM PLC_PRG VAR xBool1, xBool2 : BOOL; xResult : BOOL; END_VAR xResult := xBool1 > xBool2; // SA0051 xBool1 := NOT xBool1; // OK! xBool2 := xBool2 XOR xBool1; // OK! --> SA0051: Comparison operations on BOOL varables