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!
In other words, how can I redefine sfr's in program field,such as: main() { .... sbit ram_en=P1^2; .... }
NO, you cannot do this. The 8051 instruction set has no way to indirectly address SFRs. This is part of the processor architecture - nothing to do with any particular toolset. You will have to do something like:
sbit ram_en0=P1^0; sbit ram_en1=P1^2; : if( whatever ) { // use ram_en0 } else { // use ram_en1 }