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|
dc.l $0, start
dc.l empty_handler
dc.l empty_handler
;$10
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$20
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$30
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$40
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$50
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$60
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$70
dc.l int_4
dc.l empty_handler
dc.l int_6
dc.l empty_handler
;$80
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$90
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$A0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$B0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$C0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$D0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$E0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
;$F0
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.l empty_handler
dc.b "SEGA GENESIS "
dc.b "(c) 2015.JULY "
dc.b "Menu "
dc.b " "
dc.b " "
dc.b "Menu "
dc.b " "
dc.b " "
dc.b "MP BlstMenu-00", 0, 0
dc.b " "
dc.l $0, rom_end-1, $FF0000, $FFFFFF
dc.b " "
dc.b " "
dc.b " "
dc.b " "
dc.b "JUE "
;register addresses
VDP_DATA equ $C00000
VDP_CTRL equ $C00004
VDP_HV equ $C00008
Z80_RAM equ $A00000
IO_AREA equ $A10000
PAD1_DATA equ (IO_AREA + 3)
PAD2_DATA equ (IO_AREA + 5)
EXT_DATA equ (IO_AREA + 7)
PAD1_CTRL equ (IO_AREA + 9)
PAD2_CTRL equ (IO_AREA + 11)
EXT_CTRL equ (IO_AREA + 13)
MODE_1 equ 0
MODE_2 equ 1
SCROLL_A equ 2
WINDOW equ 3
SCROLL_B equ 4
SAT equ 5
BG_COLOR equ 7
HINT equ $A
MODE_3 equ $B
MODE_4 equ $C
HSCROLL equ $D
AUTOINC equ $F
SCROLL EQU $10
WINDOW_H equ $11
WINDOW_V equ $12
DMALEN_L equ $13
DMALEN_H equ $14
DMASRC_L equ $15
DMASRC_M equ $16
DMASRC_H equ $17
VDP_VRAM_WRITE equ $40000000
VDP_CRAM_WRITE equ $C0000000
VDP_VSRAM_WRITE equ $40000010
VDP_DMA_FLAG equ $80
vdpregset macro
move.w #(((\1) << 8) | $8000 | (\2)), (a1)
endm
vdpreg macro
dc.w (((\1) << 8) | $8000 | (\2))
endm
;Writes a normal VDP command to the control port
;\1 - VDP address
;\2 - Access type
vdpaccess macro
move.l #((\2) | (\1) << 16 & $3FFF0000 | (\1) >> 14 & 3), (a1)
endm
;Writes a DMA command to the control port
;\1 - Destination address
;\2 - Destination type
startdma macro
move.l #(\2 | VDP_DMA_FLAG | (\1 << 16) & $3FFF0000 | (\1 >> 14) & 3), (a1)
endm
DMA_SRC_68K equ 0
DMA_SRC_VRAM equ $C0
DMA_SRC_FILL equ $80
dmasrc macro
move.l #($95009600 + (\1) << 15 & $FF0000 + (\1) >> 9 & $FF), (a1)
move.w #($9700 + (\1) >> 17 & $7F | (\2)), (a1)
endm
dir_buffer equ $100000
menu_port equ $180000
MAX_DISPLAY equ 24
rsset $FFFF8000
x_pos rs.w 1
base_cmd rs.l 1
sprite_list rs.l 160
page_index rs.l MAX_DISPLAY+1
num_sprites rs.b 1
last_pad rs.b 1
selected rs.b 1
int_6:
dmasrc sprite_list, DMA_SRC_68K
;set DMA length
move.l #$94009300, d0
moveq #0, d1
move.b num_sprites.w, d1
add.w d1, d1
add.w d1, d1
move.b d1, d0
swap d0
lsr.w #8, d1
move.b d1, d0
move.l d0, (a1)
startdma $C000, VDP_VRAM_WRITE
;read gamepad in port 1
lea PAD1_DATA, a2
move.b #$40, (a2)
move.b (a2), d0
and.b #$3F, d0
move.b d0, (a2)
move.b (a2), d1
and.b #$30, d1
add.b d1, d1
add.b d1, d1
or.b d1, d0
not.b d0 ;button state is inveterted
move.b (last_pad).w, d1
eor.b d0, d1
and.b d0, d1
move.b d0, (last_pad).w
moveq #16, d2
;d0 = SACBRLUD
;d1 = newly pressed buttons
btst #1, d1
bne down
btst #0, d1
bne up
btst #7, d1
bne start_pressed
int_done:
rte
down:
;check if we are already at the bottom of the page
moveq #1, d0
add.b (selected).w, d0
move.w d0, d1
add.w d0, d0
add.w d0, d0
lea page_index.w, a2
tst.l (0, a2, d0.w)
beq int_done
move.b d1, (selected).w
add.w d2, (sprite_list).w
add.w d2, (sprite_list+8).w
rte
up:
;check if we are already at the top of the page
move.b (selected).w, d0
beq int_done
subq #1, d0
move.b d0, (selected).w
sub.w d2, (sprite_list).w
sub.w d2, (sprite_list+8).w
rte
start_pressed:
moveq #0, d0
move.b (selected).w, d0
add.w d0, d0
add.w d0, d0
lea page_index.w, a2
move.l (0, a2, d0.w), a2
tst.b (-1, a2)
bne enter_dir
;regular file
rte
enter_dir:
lea menu_port+4, a3
move.l a2, (a3)
.wait_complete
tst.w (a3)
bne .wait_complete
addq #6, a7
bra menu_start
int_4:
empty_handler:
rte
initial_regs:
vdpreg MODE_2, $4 ;Mode 5, everything turned off
vdpreg MODE_1, $4
vdpreg SCROLL_A, $20 ;Scroll a table $8000
vdpreg SCROLL_B, $05 ;Scroll b table $A000
vdpreg SAT, $60 ;SAT table $C000
vdpreg BG_COLOR, 0
vdpreg HINT, $FF
vdpreg MODE_3, 0 ;full screen scroll
vdpreg MODE_4, $87 ;40 cell mode, double-res interlace
vdpreg HSCROLL, 0
vdpreg AUTOINC, 2
vdpreg SCROLL, 1 ;64x32 scroll size
end_initial_regs
start:
lea $C00000, a0
lea $C00004, a1
moveq #(end_initial_regs-initial_regs-1), d0
lea initial_regs.w, a2
.regloop
move.w (a2)+, (a1)
dbra d0, .regloop
vdpaccess $0, VDP_CRAM_WRITE
move.w #$020, (a0)
move.w #$EEE, (a0)
move.w #$222, (a0)
;init scroll table
vdpaccess $0, VDP_VRAM_WRITE
move.w #0, (a0)
move.w #4, (a0)
;load tiles
vdpaccess $800, VDP_VRAM_WRITE
lea font(pc), a2
move.w #((arrowend-font)/4 - 1), d0
tloop:
move.l (a2)+, (a0)
dbra d0, tloop
;setup SAT
;;vdpaccess $C000, VDP_VRAM_WRITE
lea sprite_list.w, a2
;left arrow
move.l #$01080501, (a2)+
move.l #$807F0086, (a2)+
;right arrow
move.l #$01080500, (a2)+
move.l #$887F01AA, (a2)+
move.b #2, num_sprites.w
menu_start:
;clear name tables
vdpaccess $8000, VDP_VRAM_WRITE
moveq #32, d0
swap d0
move.b #32, d0
move.w #(64*64-1), d1
ploop:
move.l d0, (a0)
dbra d1, ploop
move.l #$40860002, d3
move.l d3, (a1)
move.l d3, base_cmd.w
lea dir_buffer, a6
lea menu_port, a2
move.l a6, (a2)
wait_complete:
tst.w (a2)
bne wait_complete
lea page_index.w, a3
moveq #MAX_DISPLAY-1, d7
file_loop:
tst.b (a6)+
beq done_files
addq #1, a6 ;TODO: Do something with directory flag
;skip over entries starting with a dot except ..
cmp.b #$2E, (a6)
bne normal
cmp.b #$2E, (1, a6)
beq normal
addq #1, a6
.skip_loop:
tst.b (a6)+
bne .skip_loop
addq #1, d7
move.l a6, d6
bra skip
normal:
;save entry pointer to page index
move.l a6, (a3)+
;print name on screen
moveq #0, d0
bsr print_string
move.l a6, d6
lea Newline(pc), a6
bsr print_string
skip:
;word align pointer
addq #1, d6
and.w #$FFFE, d6
move.l d6, a6
dbra d7, file_loop
done_files:
;null terminate page_index
moveq #0, d0
move.l d0, (a3)
;setup gamepad in port 1
move.b #$40, PAD1_CTRL
move.w #$8174, (a1) ;enable display, vertical interrupts, DMA
wait_forever
stop #2500
bra wait_forever
Newline:
dc.b $A, 0
align 1
;Prints a null terminated string
;a6 - pointer to string
;a0 - VDP data port
;d0 - base tile attribute
;
;Clobbers: d1.w, d2.w, d3.l
print_string:
lea widths(pc), a5
move.w x_pos.w, d2
move.l base_cmd.w, d3
.loop
moveq #0, d1
move.b (a6)+, d1
beq .end
cmp.b #$A, d1
beq .newline
tst.b (-32, a5, d1.w)
beq .narrow
add.w d0, d1
move.w d1, (a0)
addq #2, d2
bra .loop
.narrow
add.w d0, d1
move.w d1, (a0)
addq #1, d2
move.l d2, d1
;switch to other plane
and.w #$FFFE, d1
swap d1
eor.l #$20000000, d3
add.l d3, d1
move.l d1, (a1)
bra .loop
.newline
moveq #0, d2
;switch back to plane A
and.l #$DFFFFFFF, d3
;skip to next row
add.l #$00800000, d3
move.l d3, (a1)
bra .loop
.end
move.w d2, x_pos.w
move.l d3, base_cmd.w
rts
align 1
font:
incbin font_interlace_variable.tiles
fontend
arrow:
incbin arrow.tiles
arrowend:
widths:
dc.b 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1
dc.b 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0
dc.b 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1
dc.b 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
dc.b 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1
rom_end:
|
