WH Tan wrote:
> 1) Is PCL post increased by PIC after execution of instruction, or is
> it increased before execution of instruction?

During the execution of an instruction, the PC contains the address of that
instruction + 1.

> 2) Is the following set of codes have the same effect on program flow?
>
> A1 MOVLW 0x00
>    ADDWF PCL,f
>
> A2 GOTO A2
>
>
> B1 MOVLW 0xFF
>    ....
>    ADDWF PCL,f
>
> B2 GOTO $-1

I'm not sure what you are asking, but GOTO $-1 will go to the previous
instruction whereas A2 GOTO A2 will go to itself.  The assembler "$" symbol
refers to the address of the current instruction.


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