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+---- Thread: CLS/Fade out ASM Sub-routine (/showthread.php?tid=2641)
CLS/Fade out ASM Sub-routine - tubz74 - 2025-10-05
This is a small clear screen, that sort of fades out the screen pixel by pixel to the background colour. I took it from one of the Melbourne house books, can't remember which one though.
No idea if it breaks anything else, but I've not had any issues.
Code:
SUB CLSFadeOut()
' Fade out Screen Clearing
ASM
LD DE,08feh
NXTFADE:
LD A,E
RLCA
RLCA
RLCA
LD E,A
LD HL,4000H
LD BC,0018H
NXT:
LD A, (HL)
AND E
LD (HL),A
INC HL
DJNZ NXT
DEC C
JR NZ,NXT
DEC D
JR NZ,NXTFADE
LD A,(5C8DH)
LD (HL),A
LD D,H
LD E,L
INC DE
LD BC,02C0H
LDIR
LD A,(5C48H)
LD (HL),A
LD C,3FH
LDIR
END ASM
END SUBRE: CLS/Fade out ASM Sub-routine - boriel - 2025-10-05
Good one!
No, it won't break anything (only IX should be preserved (push/pop) before the function returns).
Also, it's recommended to make your labels private. To do so:
Wrap your ASM routine between
Code:
PROC
...
ENDPDeclare your labels locals after PROC, with:
LOCAL NXTFADE, NXT
:-)
If your code is BSD / MIT / Apache I can put it in the standard library for other people to use it.
RE: CLS/Fade out ASM Sub-routine - tubz74 - 2025-10-05
Happy for it to be used however by whoever - which ever licence doesn't require anything from me or from the user.