
1. CPU REGISTERS


Withing the CPU are the registers necessary for the execution of
the various commands. These are an A register (note : functions
as an 8-bit accumulator). X register, Y register (8-bit universal
register which can also be used as index register). PSW ( program
status ward). SP (stack pointer), etc. These are all 8-bit 
registersm but the PC (program counter) is made up of 16 bits.


------------------------------
            P|C               |   Program Counter      (16 bits)
------------------------------
              ----------------
             |        A       |   A Register           (8  bits)
              ----------------
------------------------------
      Y      |        A       |   (Y,A Paired 16-bit Acumulator)
------------------------------                         (16 bits)
              ----------------
             |        X       |   X Register           (8  bits)
              ----------------
              ----------------
             |        Y       |   Y Register           (8  bits)
              ----------------
              ----------------
             |       SP       |   Stack Pointer        (8  bits)
              ----------------
              ----------------
             |       PSW      |   Program Status Ward  (8  bits)
              ----------------
            /              /
           ---------------
          |N|V|P|-|H|-|Z|C|
           ---------------

           N = Negative Flag
           V = Overflow Flag
           P = Direct Page Flag
           H = Half Carry Flag
           Z = Zero Flag
           C = Carry Flag (Bit Accumulator)


