10 rem submarine tracking system (mega65 high res) 20 speed 3 : graphic clr : screen 640,400,4 30 box 0,0,639,388 40 char 14,380,2,2,2,"{CTRL+B} submarine tracking system ",$29000 50 xr=10 : pen 2 60 do 70 circle 320,190,xr 80 xr=xr+20 90 loop until xr=190 : speed 40 : sleep 2 100 do 110 xr=10 120 do 130 pen 1:circle 320,190+xr,4,1 : sleep 1 140 pen 0:circle 320,190+xr,4,1 : sleep 2 150 sound 1,16000,15 160 pen 0:circle 320,190,xr 170 pen 2:circle 320,190,xr 180 xr=xr+20 190 loop until xr=190 200 loop