请问51单片机中AR0-AR7是什么，和R0-R7区别，内部物理空间是否是同一空间

请问51单片机中AR0-AR7是什么，和R0-R7区别，内部物理空间是否是同一空间

R0 – R7：The eight 8-bit general purpose 8051 registers in the currently active register
bank. A Maximum of four register banks are available.
AR0 – AR7：Represent the absolute data addresses of R0 through R7 in the current register
bank. The absolute address for these registers will change depending on the
register bank that is currently selected. These symbols are only available when
the USING directive is given. Refer to the USING directive for more information
on selecting the register bank. These representations are suppressed by the
NOAREGS directive. Refer to the NOAREGS directive for more information.

这里已经写得很清楚了。R0~R7表示当前选中的寄存器组的寄存器0~7，而AR0~AR7表示当前选中的寄存器组的寄存器绝对地址。ARx需结合USING汇编指示共同使用，以计算出相应的绝对地址。例如若当前选中RegBank2，则R0~R7实际对应于内部空间的10H~17H单元。