Unconditional Call Instruction

CALL ( Unconditional Call) Instructions :This  instruction calls the subroutine program stored at memory  location specified  in the  instruction. The specified  memory  address will  be copied  into the  program  counter register. But before  coping  the new  address  the previous  contents  of the  program  counter  are stored  into the  stack. The instruction format is.

                                      CALL 16 bit  memory  address

Hence it  possible  to come back to the original position after completing  the subroutine  program from where  it is  called.