//header for nesasm
asm
.inesprg 1 ;//one PRG bank
.ineschr 1 ;//one CHR bank
.inesmir 0 ;//mirroring type 0
.inesmap 0 ;//memory mapper 0 (none)
.org $8000
.bank 0
endasm
///////////////////////////////////////
// This demo ROM allows the player to move Sack of Flour around the screen,
// as a demonstration of sprite drawing. Pressing the select button will
// toggle displaying him behind or in front of the background layer.
// The start button will toggle very simple physics.
array absolute $200 spritemem 256
//the program starts here on NES boot (see footer)
start:
// some init code based on Duck Hunt
// turn off the PPU
gosub vwait_start
asm
cld
sei
endasm
//now turn on the PPU
set $2000 %00100000
set $2001 %00011100 //sprites and bg visible, no sprite clipping
gosub clear_background
gosub vwait
gosub load_palette
gosub load_background
gosub init_vars
//the main program loop
mainloop:
gosub vwait_start
gosub draw_sack
gosub vwait_end
gosub joy_handler
goto mainloop
//set default sprite location
init_vars:
// We need to know where on the screen SOF is. These coordinates
// define the top left corner of the sprite set. This is 32
// pixels above his left foot, even though he is only 22 tall
set sack_x 120 //top left corner of SOF (left foot)
set sack_y 110 //top left corner of SOF (32 pixels above feet)
// We need to know which direction to draw him. The attrbute
//bytes also change, based on whether he is behind the background
set sack_facing 1 //right
set sack_r_attrib 0 //attribute byte when facing right
set sack_l_attrib %01000000 //attribute byte when facing left
// Status telling whether the select button has been released, so
// that we don't constantly turn the feature on and off every frame
set select_still_down 0
set start_still_down 0
set behind_bg 0
set use_physics 0
set ground_height 135 //for physics (based on his head, not his feet)
set gravity_dir 0 //downward
set gravity_index 0
return
//routine to draw a sprite
draw_sack:
if sack_facing = 1 goto draw_sack_right
goto draw_sack_left
//move sprite based on joystick input
joy_handler:
gosub joystick1
if joy1select = 0 set select_still_down 0
if joy1select <> 0 if select_still_down = 0 then
if behind_bg = 0 then
set sack_r_attrib %00100000
set sack_l_attrib %01100000
set behind_bg 1
goto joy_handler_1
endif
//else behind_bg = 1
set sack_r_attrib 0
set sack_l_attrib %01000000
set behind_bg 0
endif
joy_handler_1:
set select_still_down joy1select
if joy1start = 0 set start_still_down 0
if joy1start <> 0 if start_still_down = 0
set use_physics & + use_physics 1 1
joy_handler_2:
if use_physics = 1 goto joy_handler_physics
goto joy_handler_no_physics
joy_handler_no_physics:
set sack_x + sack_x joy1right
set sack_x - sack_x joy1left
set sack_y + sack_y joy1down
set sack_y - sack_y joy1up
if joy1right <> 0 set sack_facing 1
if joy1left <> 0 set sack_facing 0
return
joy_handler_physics:
// We don't bother with horizontal collision
set sack_x + sack_x joy1right
set sack_x - sack_x joy1left
if joy1right <> 0 set sack_facing 1
if joy1left <> 0 set sack_facing 0
// Handle parabolic jumping
if joy1a <> 0 if sack_y = ground_height then
set gravity_dir 1
set gravity_index 26
endif
// Handle rising (falling up)
if gravity_dir = 1 then
if gravity_index > 0 dec gravity_index
set sack_y - sack_y [gravity gravity_index]
if gravity_index = 0 set gravity_dir 0 //now go down
endif
// Handle falling down
if gravity_dir = 0 then
if gravity_index < 25 inc gravity_index
set sack_y + sack_y [gravity gravity_index]
endif
// Ground Collision
if sack_y > ground_height then
set sack_y ground_height
set gravity_index 0
endif
return
// Draw SOF facing to the right
// We have 4 sprites for him. up-left, down-left,
// up-right, and down-right. They are all 8x16
draw_sack_right:
set $2003 0
set $2004 sack_y
set $2004 32
set $2004 sack_r_attrib
set $2004 sack_x
set $2004 + sack_y 16
set $2004 34
set $2004 sack_r_attrib
set $2004 sack_x
set $2004 sack_y
set $2004 36
set $2004 sack_r_attrib
set $2004 + sack_x 8
set $2004 + sack_y 16
set $2004 38
set $2004 sack_r_attrib
set $2004 + sack_x 8
return
// Draw SOF facing left
// Note that, since he is made of 4 sprites, we have
// to flip the horizontal drawing order, in addition
// to flipping the sprites themselves
draw_sack_left:
set $2003 0
set $2004 sack_y
set $2004 36
set $2004 sack_l_attrib
set $2004 sack_x
set $2004 + sack_y 16
set $2004 38
set $2004 sack_l_attrib
set $2004 sack_x
set $2004 sack_y
set $2004 32
set $2004 sack_l_attrib
set $2004 + sack_x 8
set $2004 + sack_y 16
set $2004 34
set $2004 sack_l_attrib
set $2004 + sack_x 8
return
//load the colors
load_palette:
//set the PPU start address (background color 0)
set $2006 $3f
set $2006 0
set $2007 $31 //sky blue
set $2007 $1a //dark green
set $2007 $29 //light green
set $2007 $28 //tan
//set the PPU start address (foreground color 0)
set $2006 $3f
set $2006 $10
set $2007 $31 //mirror sky blue
set $2007 $0e //black
set $2007 $30 //white
set $2007 $10 //grey
return
// draw the simple background
load_background:
gosub vwait
gosub load_grass_top
gosub vwait
gosub load_grass_bottom
gosub vwait
gosub load_bottom_bricks
return
load_grass_top:
set $2006 $22
set $2006 $65
set y 0
load_grass_top_1:
set $2007 2
set $2007 3
set $2007 0
set $2007 0
set $2007 0
set $2007 0
set $2007 0
inc y
if y <> 4 goto load_grass_top_1
return
load_grass_bottom:
set $2006 $22
set $2006 $80
set y 0
load_grass_bottom_1:
set $2007 22
set $2007 23
set $2007 24
set $2007 25
set $2007 22
set $2007 18
set $2007 19
inc y
if y <> 5 goto load_grass_bottom_1
return
load_bottom_bricks:
set $2006 $22
set $2006 $a0
set y 0
load_bottom_bricks_1:
set $2007 4
set $2007 5
inc y
if y <> 16 goto load_bottom_bricks_1
set y 0
load_bottom_bricks_2:
set $2007 20
set $2007 21
inc y
if y <> 16 goto load_bottom_bricks_2
return
gravity: //32 bytes
data 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1
data 2, 1, 2, 1, 2, 2, 2, 3, 2, 2, 3, 3, 3, 3, 3, 3
///////////////////////////////////////////////
//update joystick button status
joystick1:
set $4016 1 //first strobe byte
set $4016 0 //second strobe byte
set joy1a & [$4016] 1
set joy1b & [$4016] 1
set joy1select & [$4016] 1
set joy1start & [$4016] 1
set joy1up & [$4016] 1
set joy1down & [$4016] 1
set joy1left & [$4016] 1
set joy1right & [$4016] 1
return
//wait for the start of the vertical blanking interval
vwait_start:
asm
bit $2002
bpl vwait_start
endasm
return
//wait for the end of the vertical blanking interval
vwait_end:
asm
bit $2002
bmi vwait_end
endasm
set a 0
set $2005 a
set $2005 a
set $2006 a
set $2006 a
return
//wait until screen refresh
vwait:
gosub vwait_start
gosub vwait_end
return
//clear the first background buffer (0)
clear_background:
gosub vwait
gosub clear_background_one
gosub vwait
gosub clear_background_two
return
clear_background_one:
set clear_background_temp $20
gosub clear_background_helper
set clear_background_temp $21
gosub clear_background_helper
set clear_background_temp $22
gosub clear_background_helper
set clear_background_temp $23
gosub clear_background_helper
gosub vwait
return
clear_background_two:
set clear_background_temp $24
gosub clear_background_helper
set clear_background_temp $25
gosub clear_background_helper
set clear_background_temp $26
gosub clear_background_helper
s
Nbasic编译为Nes
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2009-06-29
17:53:18
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收藏 464KB RAR 举报 
Nbasic to Nes.rar （9个子文件） 
Nbasic to Nes 
bg1.bat 44B
test.txt 9KB cygwin1.dll 949KB bgdemo.chr 4KB test.asm 9KB test.nes 24KB Read Me.txt 2KB
nbasic.exe 81KB nesasm.exe 137KB资源评论
Disn253472013-02-06可以用的。不过要仔细琢磨。
