[SAMPLE19_0] SAMPLE
10 REM SAMPLE19_0
12 rem This is scroll of graphic_display”
20 CLS 3
30 XD=40:YD=20
40 'BYTE=( (XD+7) \8) * YD *3 +4
50 BYTE=(XD +1) * YD *3 +4
60 FACT= BYTE\2+1
70 DIM G%(FACT)
80 LINE (0,0)-STEP(XD-1,YD-1),1,B
90 CIRCLE (XD/2 , YD/2 ), YD/2,2
100 GET (0,0)-STEP(XD-1,YD-1),G%
110 FOR X=0 TO 500 STEP 100
120 PUT (x,100), G%
130 NEXT
200 FOR X=0 TO 500 STEP 100
210 PUT (X,200), G%, PRESET
220 NEXT
300 FOR Y=0 TO 479
310@ROLL 1
320 NEXT Y
900 END