设计的CPU字长为16位，可以实现子程序调用，分支，循环及各种算术逻辑运算等功能。 访存的指令采用寄存器间址寻址(R)或是基址寻址X(R)实现， -Design CPU 16 word length can be achieved subroutine calls, branches, loops, and various arithmetic and logical operations and other functions. Between instruction fetch re