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z80
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Replace tabs with spaces

This commit is contained in:
Pedro de Oliveira 2014-08-20 04:59:00 +01:00
parent e5a5eec99d
commit 161b0956e8
1 changed files with 31 additions and 31 deletions
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56
starfield/main.asm
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@ -9,9 +9,9 @@ clr_screen EQU $0daf ; ROM routine to clear the screen
; Screen is 256x192 ; Screen is 256x192
; Star Structure ; Star Structure
; X - 1 Byte $00 - $ff ; X 1 Byte $0 - $ff
; Y - 1 Byte $00 - $c0 ; Y 1 Byte $0 - $c0
; Speed - 1 Byte $1 - $3 ; Speed 1 Byte $1 - $3
MAX_STARS EQU 10 MAX_STARS EQU 10
start start
@ -229,33 +229,33 @@ PROC
; On Entry: D reg = X coord, E reg = Y coord ; On Entry: D reg = X coord, E reg = Y coord
; On Exit: HL = screen address, A = pixel postion ; On Exit: HL = screen address, A = pixel postion
get_screen_address get_screen_address
ld a,e ld a,e
and %00000111 and %00000111
ld h,a ld h,a
ld a,e ld a,e
rra rra
rra rra
rra rra
and %00011000 and %00011000
or h or h
or %01000000 or %01000000
ld h,a ld h,a
; Calculate the low byte of the screen address and store in L reg. ; Calculate the low byte of the screen address and store in L reg.
ld a,d ld a,d
rra rra
rra rra
rra rra
and %00011111 and %00011111
ld l,a ld l,a
ld a,e ld a,e
rla rla
rla rla
and %11100000 and %11100000
or l or l
ld l,a ld l,a
; Calculate pixel position and store in A reg. ; Calculate pixel position and store in A reg.
ld a,d ld a,d
and %00000111 and %00000111
ret ret
ENDP ENDP