.endm
-/* For indirect (variable) addresses.
- Destroys d6-d7. */
-.macro VRAM_ADDR_var reg adr
- move.l \adr,d6
+# make VDP word from address adr to d0
+# destroys d7
+.macro VRAM_ADDR_var adr
+ move.l \adr,d0
move.l \adr,d7
- and.w #0x3fff,d6
+ and.w #0x3fff,d0
lsr.w #7,d7
lsr.w #7,d7
- add.w #0x4000,d6
- lsl.l #7,d6
- lsl.l #7,d6
- lsl.l #2,d6
- or.l d7,d6
- move.l d6,\reg
+ add.w #0x4000,d0
+ lsl.l #7,d0
+ lsl.l #7,d0
+ lsl.l #2,d0
+ or.l d7,d0
.endm
#################################################
colors:
- dc.w 0x0040,0x0080,0x000e,0x00e0,0x0e00,0x00ee
-pattern:
- dc.l 0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,0x00000000,0x00000000
- dc.l 0x22334455,0x22334455,0x22334455,0x22334455,0x22334455,0x22334455,0x22334455,0x22334455
- /* shadow sprite */
- dc.l 0x00000fff
- dc.l 0x0000ffff
- dc.l 0x00ffffff
- dc.l 0x00ffffff
- dc.l 0x0fffffff
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0xffffffff
- /* */
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0x0fffffff
- dc.l 0x00ffffff
- dc.l 0x00ffffff
- dc.l 0x0000ffff
- dc.l 0x00000fff
- /* */
- dc.l 0xfff00000
- dc.l 0xffff0000
- dc.l 0xffffff00
- dc.l 0xffffff00
- dc.l 0xfffffff0
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0xffffffff
- /* */
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0xffffffff
- dc.l 0xfffffff0
- dc.l 0xffffff00
- dc.l 0xffffff00
- dc.l 0xffff0000
- dc.l 0xfff00000
- /* hilight sprite */
- dc.l 0x00000eee
- dc.l 0x0000eeee
- dc.l 0x00eeeeee
- dc.l 0x00eeeeee
- dc.l 0x0eeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- /* */
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0x0eeeeeee
- dc.l 0x00eeeeee
- dc.l 0x00eeeeee
- dc.l 0x0000eeee
- dc.l 0x00000eee
- /* */
- dc.l 0xeee00000
- dc.l 0xeeee0000
- dc.l 0xeeeeee00
- dc.l 0xeeeeee00
- dc.l 0xeeeeeee0
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- /* */
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeeee
- dc.l 0xeeeeeee0
- dc.l 0xeeeeee00
- dc.l 0xeeeeee00
- dc.l 0xeeee0000
- dc.l 0xeee00000
+ dc.w 0x0000,0x0eee
+colors_end:
+
+# pattern:
sprite_data:
/* Y size link attr X */
- dc.w 10+128; dc.b 0x05; dc.b 1; dc.w 0x6002; dc.w 0
- dc.w 30+128; dc.b 0x05; dc.b 2; dc.w 0x6006; dc.w 0
- dc.w 60+128; dc.b 0x05; dc.b 3; dc.w 0xe002; dc.w 0
- dc.w 80+128; dc.b 0x05; dc.b 4; dc.w 0xe006; dc.w 0
- dc.w 120+128; dc.b 0x05; dc.b 5; dc.w 0x6002; dc.w 0
- dc.w 140+128; dc.b 0x05; dc.b 6; dc.w 0x6006; dc.w 0
- dc.w 170+128; dc.b 0x05; dc.b 7; dc.w 0xe002; dc.w 0
- dc.w 190+128; dc.b 0x05; dc.b 0; dc.w 0xe006; dc.w 0
+ dc.w 0; dc.b 0x05; dc.b 0; dc.w 0x6002; dc.w 0
sprite_data_end:
+hello:
+ .ascii "hello world"
##################################################
# #
# #
##################################################
+.align 2
+
main:
/* Initialize VDP */
jsr init_gfx
/* Load color data */
movea.l #0,a3
- move.l #colors,a4
- moveq.l #6,d4
+ movea.l #colors,a4
+ moveq.l #(colors_end-colors)/2,d4
jsr load_colors
/* load patterns */
movea.l #0,a3
- movea.l #pattern,a4
- move.l #10,d4
+ movea.l #font,a4
+ move.l #128,d4
jsr load_tiles
/* generate A layer map */
- movea.l #0xe000+10*2,a6
+ movea.l #0xe000,a6
move.l #28-1,d4
lmaploop0:
movea.l a6,a3
jsr load_prepare
- moveq.l #6-1,d3
-0: move.l #0x00010001,(a3)
- dbra d3,0b
-
- moveq.l #9-1,d3
-0: move.l #0x80018001,(a3)
+ move.l #64/2-1,d3
+0: move.l #0x00000000,(a3)
dbra d3,0b
add.l #64*2,a6
dbra d4,lmaploop0
/* generate B layer map */
- movea.l #0xc000+64*14*2,a3
+ movea.l #0xc000,a3
jsr load_prepare
- move.l #64*14/2-1,d3
-0: move.l #0x80008000,(a3)
+ move.l #64*28/2-1,d3
+0: move.l #0x00000000,(a3)
dbra d3,0b
/* upload sprite data */
jsr wait_vsync
+ movea.l #hello,a0
+ moveq.l #1,d0
+ moveq.l #1,d1
+ jsr print
+
##################################################
# #
# MAIN LOOP #
##################################################
forever:
- movea.l #vtimer,a0
- move.l (a0),d4
- and.w #0x1ff,d4
- movea.l #0xfc06,a6
- moveq.l #8-1,d5
-0:
- movea.l a6,a3
- jsr load_prepare
- move.w d4,(a3)
- addq.w #8,a6
- dbra d5,0b
jsr wait_vsync
bra forever
init_gfx:
move.l #GFXCNTL,a3
- write_vdp_reg 0,(VDP0_E_DISPLAY + VDP0_PLTT_FULL)
- write_vdp_reg 1,(VDP1_E_VBI + VDP1_E_DISPLAY + VDP1_E_DMA + VDP1_RESERVED)
+ write_vdp_reg 0,(VDP0_E_DISPLAY | VDP0_PLTT_FULL)
+ write_vdp_reg 1,(VDP1_E_VBI | VDP1_E_DISPLAY | VDP1_E_DMA | VDP1_RESERVED)
write_vdp_reg 2,(0xe000 >> 10) /* Screen map a adress */
write_vdp_reg 3,(0xe000 >> 10) /* Window address */
write_vdp_reg 4,(0xc000 >> 13) /* Screen map b address */
write_vdp_reg 5,(0xfc00 >> 9) /* Sprite address */
write_vdp_reg 6,0
- write_vdp_reg 7,1 /* Border color */
+ write_vdp_reg 7,0 /* Backdrop color */
write_vdp_reg 10,1 /* Lines per hblank interrupt */
write_vdp_reg 11,0 /* 2-cell vertical scrolling */
- write_vdp_reg 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320 | VDP12_SPR_SHADOWS)
- write_vdp_reg 13,(0x6000 >> 10) /* Horizontal scroll address */
+ write_vdp_reg 12,(VDP12_SCREEN_V224 | VDP12_SCREEN_H320)
+ write_vdp_reg 13,(0x8000 >> 10) /* Horizontal scroll address */
write_vdp_reg 15,2
- write_vdp_reg 16,(VDP16_MAP_V32 + VDP16_MAP_H64)
+ write_vdp_reg 16,(VDP16_MAP_V32 | VDP16_MAP_H64) /* layer size */
write_vdp_reg 17,0
write_vdp_reg 18,0xff
rts
# a3: VRAM base #
# a4: pattern address #
# d4: number of tiles to load #
-# Destroys a2,d0,d6-d7... #
+# Destroys a2,d0,d7... #
# #
#################################################
load_tiles:
move.l #GFXCNTL,a2
- VRAM_ADDR_var d0,a3
+ VRAM_ADDR_var a3
move.l d0,(a2)
lsl #3,d4
rts
+# Prepare to write to VDP RAM @a3
+# a3: VRAM base
+# a3 set to VDP data port for convenience
+# destroys a2,d0,d7
+
load_prepare:
move.l #GFXCNTL,a2
- VRAM_ADDR_var d0,a3
+ VRAM_ADDR_var a3
move.l d0,(a2)
move.l #GFXDATA,a3
rts
-#################################################
-# #
-# Clear one of the screen maps #
-# #
-# Parameters: #
-# a0: Map address #
-# d0: Data to write to each map entry #
-# #
-#################################################
-
-clear_map:
- move.l #GFXCNTL,a4
- VRAM_ADDR_var d1,a0
- move.l d1,(a4)
- move.l #GFXDATA,a3
- move.w #1023,d1 /* Loop counter */
-_clear_map_loop:
- move.w d0,(a3)
- move.w d0,(a3)
- dbra d1,_clear_map_loop
- rts
-
-
#################################################
# #
# Load color data from ROM #
rts
+#################################################
+##
+## print
+# a0 - string
+# d0 - x
+# d1 - y
+
+print:
+ lsl.w #6,d1
+ add.w d1,d0
+ movea.l #0xe000,a6
+ lsl.w #1,d0
+ add.w d0,a6
+ moveq.l #0,d1
+
+_print_loop:
+ move.b (a0)+,d1
+ beq _print_end
+
+ move.l a6,a3
+ jsr load_prepare
+ move.w d1,(a3)
+ addq.l #2,a6
+ jmp _print_loop
+
+_print_end:
+ rts
+
#################################################
# #
#################################################
.bss
+
+# used by sega_gcc.s
.globl htimer
.globl vtimer
.globl rand_num
htimer: .long 0
vtimer: .long 0
rand_num: .long 0
-scrollx: .long 0
+
+#
.end
notaz.gp2x.de / megadrive.git / commitdiff