SA0148: Unusual bit access

Detects bit access that is not made to bitfield data types (‎BYTE‎, ‎WORD‎, ‎DWORD‎, and ‎LWORD‎). The IEC 61131-3 standard permits only bit access to bitfield data types. However, the CODESYS compiler also permits bit access to unsigned data types.

Example

PROGRAM PLC_PRG
VAR
	iTemp1 : INT;
	diTemp3 : DINT;
	uliTemp4 : ULINT;
	siTemp5 : SINT;
	usiTemp6 : USINT;
	byTemp2 : BYTE;
END_VAR

iTemp1.3 := TRUE;     // SA0148
diTemp3.4 := TRUE;    // SA0148
uliTemp4.18 := FALSE; // SA0148
siTemp5.2 := FALSE;   // SA0148
usiTemp6.3 := TRUE;   // SA0148
byTemp2.5 := FALSE;   // no error because BYTE is a bit field

--> SA0148: Unusual bit access - strict