100 CLEAR 10:SCREEN 0
  110 X=120:Y=X
  120 POKE 0,0,STRING$(512,X)
  130 P=PAD(0,1)
  140 IF P AND @PAD_UP THEN Y=Y-1
  150 IF P AND @PAD_DOWN THEN Y=Y+1
  160 IF P AND @PAD_LEFT THEN X=X-1
  170 IF P AND @PAD_RIGHT THEN X=X+1
  180 POKE 0,T,X:POKE 1,T,Y
  190 FOR I=0 TO 31:U=(I+T-31)AND 255
  200 PSET (PEEK(0,U),PEEK(1,U)),I
  210 NEXT
  220 T=(T+1)AND 255:VSYNC :GOTO 130