If you wish to link a variable directly to a definite address, then you must declare the variable with the keyword AT. The advantage of such a procedure is that you can assign a meaningful name to an address, and that any necessary changes of an incoming or outgoing signal will only have to be made in one place (e.g., in the declaration).

Notice that variables requiring an input cannot be accessed by writing.

xCounterHeat7 AT %QX0.0: BOOL;
wLightcabinetimpulse AT %IW2: WORD;
xDownload AT %MX2.2: BOOL;