2023-05-05 17:12:43 -04:00

304 lines
4.7 KiB
ArmAsm

; Double Hi-res / Double lo-res mode switch fun
; by Vince `deater` Weaver
.include "zp.inc"
.include "hardware.inc"
double:
;================================
; detect model
;================================
jsr detect_appleii_model
;===================
; machine workarounds
;===================
; mostly IIgs
;===================
; thanks to 4am who provided this code from Total Replay
lda ROM_MACHINEID
cmp #$06
bne not_a_iigs
sec
jsr $FE1F ; check for IIgs
bcs not_a_iigs
; gr/text page2 handling broken on early IIgs models
; this enables the workaround
jsr ROM_TEXT2COPY ; set alternate display mode on IIgs
cli ; enable VBL interrupts
; also set background color to black instead of blue
lda NEWVIDEO
and #%00011111 ; bit 7 = 0 -> IIgs Apple II-compat video modes
; bit 6 = 0 -> IIgs 128K memory map same as IIe
; bit 5 = 0 -> IIgs DHGR is color, not mono
; bits 0-4 unchanged
sta NEWVIDEO
lda #$F0
sta TBCOLOR ; white text on black background
lda #$00
sta CLOCKCTL ; black border
sta CLOCKCTL ; set twice for VidHD
not_a_iigs:
;================================
; Clear screen and setup graphics
;================================
jsr SETGR ; set lo-res 40x40 mode
; set 80-store mode
sta EIGHTYSTOREON ; PAGE2 selects AUX memory
bit PAGE1
;===================
; draw lo-res lines
ldx #39
draw_lores_lines:
txa
tay
jsr SETCOL
lda #47
sta V2
lda #0
jsr VLINE ; VLINE A,$2D at Y
dex
bpl draw_lores_lines
; copy to 800 temporarily
; yes this is a bit of a hack
ldy #0
cp_loop:
lda $400,Y
sta $800,Y
lda $500,Y
sta $900,Y
lda $600,Y
sta $A00,Y
lda $700,Y
sta $B00,Y
iny
bne cp_loop
bit PAGE1
; copy to $400 in AUX
bit PAGE2 ; $400 now maps to AUX:$400
ldy #0
cp2_loop:
lda $800,Y
eor #$FF
sta $400,Y
lda $900,Y
eor #$FF
sta $500,Y
lda $A00,Y
eor #$FF
sta $600,Y
lda $B00,Y
eor #$FF
sta $700,Y
iny
bne cp2_loop
bit PAGE1
;=======================================
; load double hi-res image to MAIN:PAGE1
;=======================================
lda #<image_dhgr_bin
sta ZX0_src
lda #>image_dhgr_bin
sta ZX0_src+1
lda #$20
jsr full_decomp
;=======================================
; load double hi-res image to AUX:PAGE1
;=======================================
bit PAGE2 ; map in AUX (80store)
lda #<image_dhgr_aux
sta ZX0_src
lda #>image_dhgr_aux
sta ZX0_src+1
lda #$20
jsr full_decomp
;=================================
; load hi-res image to MAIN:PAGE2
;=================================
; turn off eightystore
sta EIGHTYSTOREOFF
lda #<image_hgr
sta ZX0_src
lda #>image_hgr
sta ZX0_src+1
lda #$40
jsr full_decomp
sta FULLGR
; wait for vblank on IIe
; positive? during vblank
wait_vblank_iie:
lda VBLANK
bmi wait_vblank_iie ; wait for positive (in vblank)
wait_vblank_done_iie:
lda VBLANK ; wait for negative (vlank done)
bpl wait_vblank_done_iie
;
double_loop:
;===========================
; text mode first 6*4 (24) lines
; each line 65 cycles (25 hblank+40 bytes)
; 3 LINES 80-COL AN3
sta SET80COL ; 4
bit SET_TEXT ; 4
; wait 6*4=24 lines
; (24*65)-8 = 1560-8 = 1552
jsr delay_1552
; 3 LINES 40-COL AN3
sta CLR80COL ; 4
bit SET_TEXT ; 4
jsr delay_1552
; 3 LINES 40-col LORES AN3
lda LORES ; 4
bit SET_GR ; 4
jsr delay_1552
; 3 LINES 80-col DLORES AN3
sta SET80COL ; 4
sta CLRAN3 ; 4
jsr delay_1552
; 3 lines 40-col LORES
sta CLR80COL ; 4
sta SETAN3 ; 4 ; doublehiresoff
jsr delay_1552
; 3 lines HIRES PAGE2
sta HIRES ; 4
sta PAGE2 ; 4
jsr delay_1552
; 3 lines Double-hires
sta SET80COL ; 4 ; set 80 column mode
sta CLRAN3 ; 4 ; doublehireson
jsr delay_1552
; 3 line Double-HIRES
; sta PAGE1 ; 4
sta SET_GR ; 4
sta SET_GR ; 4
jsr delay_1552
;==================================
; vblank = 4550 cycles
; Try X=226 Y=4 cycles=4545
skip_vblank:
nop
ldy #4 ; 2
loop3: ldx #226 ; 2
loop4: dex ; 2
bne loop4 ; 2nt/3
dey ; 2
bne loop3 ; 2nt/3
jmp double_loop ; 3
;=======================================================
; need to align because if we straddle a page boundary
; the time counts end up off
.align $100
; actually want 1552-12 (6 each for jsr/rts)
; 1540
; Try X=15 Y=19 cycles=1540
delay_1552:
ldy #19 ; 2
loop5: ldx #15 ; 2
loop6: dex ; 2
bne loop6 ; 2nt/3
dey ; 2
bne loop5 ; 2nt/3
rts
.include "pt3_lib_detect_model.s"
; .include "pt3_lib_mockingboard_setup.s"
; .include "pt3_lib_mockingboard_detect.s"
.include "zx02_optim.s"
image_hgr:
.incbin "graphics/sworg_hgr.hgr.zx02"
image_dhgr_aux:
.incbin "graphics/sworg_dhgr.aux.zx02"
image_dhgr_bin:
.incbin "graphics/sworg_dhgr.bin.zx02"