10 A=0
20 HPIB 0
30 DISP A
40 A=A+1
50 IF A MOD 2=0 THEN 100
60 SETLED 1,40,0,0 @ SETLED 2,0,0,40
70 GOTO 20
100 SETLED 1,0,0,40 @ SETLED 2,40,0,0
110 GOTO 20
9999 END