10 'Шахматная доска
20 COLOR 15,1,1:CLS:SCREEN 3
50 FOR I=0 TO 7 STEP 2
60    VPOKE I,&HF1:VPOKE I+1,&H1F
70 NEXT
80  FOR I=BASE(5*3+0) TO I+767
90     VPOKE I,0
100 NEXT
110 GOTO 110