In my application, I want to easily change address of SFR include user's commands. Such as: sbit ram_en=P1^0; ...... /*In another place, I want to change ram_en to P1^2 dynamiclly.*/ I am try to do this(not definition field) in my code: ... sbit ram_en=P1^2; .... But it can not pass when compiling. So, how can I implement this function? Best regards!