mirror of
https://github.com/cc65/cc65.git
synced 2024-06-19 14:29:40 +00:00
88 lines
2.1 KiB
ArmAsm
88 lines
2.1 KiB
ArmAsm
.constructor initconio, 24
|
|
|
|
.import vdc_init
|
|
.import psg_init
|
|
.import colors
|
|
.import _pce_font
|
|
.importzp ptr1, tmp1
|
|
|
|
.include "pce.inc"
|
|
.include "extzp.inc"
|
|
|
|
.segment "ONCE"
|
|
initconio:
|
|
jsr vdc_init
|
|
jsr psg_init
|
|
jsr load_font
|
|
|
|
set_palette:
|
|
stz VCE_ADDR_LO
|
|
stz VCE_ADDR_HI
|
|
|
|
clx
|
|
@lp: ldy #16 ; size of a palette
|
|
|
|
@lp1: lda colors,x
|
|
sta VCE_DATA_LO
|
|
lda colors+1,x
|
|
sta VCE_DATA_HI
|
|
dey
|
|
bne @lp1
|
|
|
|
inx
|
|
inx
|
|
cpx #16 * 2 ; 16 palettes
|
|
bne @lp
|
|
|
|
sty BGCOLOR ; white on black
|
|
iny
|
|
sty CHARCOLOR
|
|
|
|
VREG VDC_CR, $0088 ; enable background and vertical-blank interrupt
|
|
rts
|
|
|
|
; Load the conio font into the VDC.
|
|
load_font:
|
|
VREG VDC_MAWR, $2000
|
|
st0 #VDC_VWR
|
|
|
|
stz tmp1 ; #%00000000
|
|
bsr copy ; make normal characters
|
|
|
|
dec tmp1 ; #%11111111
|
|
; bsr copy ; make reversed characters
|
|
; rts ; (fall through)
|
|
|
|
; Point to the font data.
|
|
copy: lda #<_pce_font
|
|
ldx #>_pce_font
|
|
sta ptr1
|
|
stx ptr1+1
|
|
|
|
ldy #$80 ; 128 chars
|
|
charloop:
|
|
ldx #$08 ; 8 bytes/char
|
|
lineloop:
|
|
lda (ptr1)
|
|
eor tmp1
|
|
sta VDC_DATA_LO ; bitplane 0
|
|
st2 #>$0000 ; bitplane 1
|
|
|
|
inc ptr1 ; increment font pointer
|
|
bne @noC
|
|
inc ptr1+1
|
|
@noC: dex
|
|
bne lineloop ; next bitplane-0 byte
|
|
|
|
ldx #$08 ; fill bitplanes 2 and 3 with 0
|
|
fillloop:
|
|
st1 #<$0000
|
|
st2 #>$0000
|
|
dex
|
|
bne fillloop ; next byte
|
|
|
|
dey
|
|
bne charloop ; next character
|
|
|
|
rts
|