Routines
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6800: Blit 8x8 character bitmap at DF offset.
Used by the routines at StrPrint, Screen_DrawColAndScroll, Score_UpdateOnScreen, Sprite_EraseAll and Items_Draw.
Input
A Character to blit
HL Position, offset from DF
CharBlit 6800 PUSH HL
6801 CP $80
6803 JR C,CharBlit_0
6805 LD DE,($5C7B) Point to UDG address.
6809 SUB $90
680B JR CharBlit_1
CharBlit_0 680D LD DE,($5C36) Point to chars.
6811 INC D
6812 SUB $20
CharBlit_1 6814 LD H,$00 Calculate bitmp address of char(A)
6816 LD L,A
6817 ADD HL,HL
6818 ADD HL,HL
6819 ADD HL,HL
681A ADD HL,DE
681B POP DE
681C PUSH HL
681D LD HL,$4000 Calculate screen address using offset.
6820 DEC DE
6821 ADD HL,DE
6822 LD A,D
6823 CP $00
6825 JR Z,CharBlit_2
6827 LD BC,$0700
682A ADD HL,BC
682B AND $FE
682D JR Z,CharBlit_2
682F ADD HL,BC
CharBlit_2 6830 POP DE
6831 LD B,$08
CharBlit_3 6833 LD A,(DE) Blit 8 lines of bitmap
6834 LD (HL),A
6835 INC DE
6836 INC H
6837 DJNZ CharBlit_3
6839 RET
683A NOP
683B NOP
683C NOP
683D NOP
683E NOP
683F NOP
Up: Map Next: 6840