SCREEN4 vertical scroll

gistfile1.txt

10 SCREEN 4: COLOR 15,1,4:C%=0

20 REM Ajusta tabelas de VRAM
21 VDP(2)=&H10
22 VDP(3)=&HFF
23 VDP(11)=&H0
24 VDP(4)=&H3
25 VDP(5)=&H8F
26 VDP(12)=&H0
27 VDP(6)=&H9
28 DEFUSR=&H41:X=USR(0)

30 REM Limpa regiao de memoria escondida
31 FOR I%=&H1800 TO &H1FFF: VPOKE I%,0:COLOR,,RND(1)*15:NEXT
32 FOR I%=&H3800 TO &H3FFF:VPOKE I%,1:COLOR,,RND(1)*15:NEXT
33 FOR I%=0 TO 255:VPOKE &H4300+I%,I%:COLOR,,RND(1)*15:NEXT

40 REM Preenchendo tabela de cores
41 FOR J%=0 TO 3
42 FOR I%=0 to 255
43 FOR K%=0 to 7
44 VPOKE &H2000+J%*2048+K%*256+I%,&HF2+K%+J%:COLOR,,RND(1)*15
45 NEXT:NEXT:NEXT

50 OPEN"GRP:"FOROUTPUTAS#1
51 FOR K%=0 TO 191 STEP 64
52 FOR J%=0 TO 63 STEP 8
53 FOR I%=0 TO 31
54 A$="BM"+STR$(I%*8)+","+STR$(K%+J%):DRAW A$
55 IF J%=0 THEN GOSUB 60 ELSE GOSUB 61
56 COLOR,,RND(1)*15:NEXT:NEXT:NEXT
57 FOR I%=0 TO 2048:A=VPEEK(I%):VPOKE &H1800+I%,A:NEXT

58 DEFUSR=&H44:X=USR(0)
59 FOR I=0 TO 255 STEP .125: VDP(24)=I:NEXT:GOTO 59

60 PRINT #1,CHR$(1)+CHR$(65+I%): RETURN
61 PRINT #1,CHR$(J%*4+I%): RETURN