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Addressing Modes

The following addressing modes have been implemented:

Register  : Data is contained in given register
            example: mov a, b      ; a=b

Immediate : Data if given in the word following the op. cod (operand).
            example: mvi  a, data  ;a=data

Direct    : Data is in the memory location which address is given in the word following the op. cod. (operand)
            example: ld a, addr    ; a=[addr]

Indirect  : Data is in the memory location which address is contained in a register used as a memory pointer
            example: ldx a, d      ; a=[d]

Relative  : (Branch only). Jump to OFF_SET relative to current instruction address. The OFF_SET if given as an operand.
            example: jnzr OFF_SET  ; pc=pc+OFF_SET

Relative Indirect: (Branch only). The OFF_SET is the content of given register.
           example: jnzrx  d      ; pc=pc+d

Stack     : Data comes from the Stack which is always pointed by register SP
            example:  pop a          ; sp=sp+1, a=[sp]