stl question siemens s7-400

      M001: NOP   0

      L     #PUNTATORE 
      L     16
      *D    
      LAR1  //calculate address offset

      OPN   "ISTROGRAMMA"

      L     DBW [AR1,P#0.0] //load word from block ISTROGRAMMA with previuosly calculated offset
      T     DBW [AR1,P#2.0]

      L     DBW [AR1,P#100.0]// same as above just add 100.0 offset to calculated
      T     DBW [AR1,P#102.0]

      L     #PUNTATORE
      L     1
      -D    
      T     #PUNTATORE //subtract 1 from var PUNTATORE  
      L     0
      >=D   
      JC    M001 //jump to M001 if PUNATORE > or = 0