code: def instruction_ADD16(self, opcode, m, register):
          
          assert register.WIDTH == 16
          old = register.value
          r = old + m
          register.set(r)
  #        log.debug("$%x %02x %02x ADD16 %s: $%02x + $%02x = $%02x" % (
  #            self.program_counter, opcode, m,
  #            register.name,
  #            old, m, r
  #        ))
          self.clear_NZVC()
          self.update_NZVC_16(old, m, r)
docs: Adds the 16-bit memory value into the 16-bit accumulator
  
          source code forms: ADDD P
  
          CC bits "HNZVC": -aaaa