common/ppu.h

   1 ;
   2 ;    Copyright (C) 2004, 2005 Kent Hansen.
   3 ;
   4 ;    This file is part of Neotoxin.
   5 ;
   6 ;    Neotoxin is free software; you can redistribute it and/or modify
   7 ;    it under the terms of the GNU General Public License as published by
   8 ;    the Free Software Foundation; either version 2 of the License, or
   9 ;    (at your option) any later version.
  10 ;
  11 ;    Neotoxin is distributed in the hope that it will be useful,
  12 ;    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;    GNU General Public License for more details.
  15 ;
  16 ;    You should have received a copy of the GNU General Public License
  17 ;    along with this program; if not, write to the Free Software
  18 ;    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 ;
  20
  21 ; PPU defines.
  22
  23 .ifndef PPU_H
  24 .define PPU_H
  25
  26 ; Hardware regs.
  27 PPU_CTRL0_REG       .equ    $2000
  28 PPU_CTRL1_REG       .equ    $2001
  29 PPU_STATUS_REG      .equ    $2002
  30 PPU_SCROLL_REG      .equ    $2005
  31 PPU_ADDR_REG        .equ    $2006
  32 PPU_IO_REG          .equ    $2007
  33
  34 ; Records which describe PPU reg layouts.
  35 .record ppu_ctrl0 nmi_on_vblank:1, pad0:1, sprite_size:1, bg_table:1, sprite_table:1, ppu_addr_inc:1, name_table:2
  36 .record ppu_ctrl1 emph:3, sprite_on:1, bg_on:1, sprite_clip:1, bg_clip:1, mono:1
  37 .record ppu_status vblank:1, sprite0:1, sprite_overflow:1, pad0:5
  38
  39 ; Field masks.
  40 PPU_CTRL0_NMI               .equ    mask ppu_ctrl0::nmi_on_vblank
  41 PPU_CTRL0_SPRITE_SIZE       .equ    mask ppu_ctrl0::sprite_size
  42 PPU_CTRL0_BG_TABLE          .equ    mask ppu_ctrl0::bg_table
  43 PPU_CTRL0_SPRITE_TABLE      .equ    mask ppu_ctrl0::sprite_table
  44 PPU_CTRL0_PPU_ADDR_INC      .equ    mask ppu_ctrl0::ppu_addr_inc
  45 PPU_CTRL0_NAME_TABLE        .equ    mask ppu_ctrl0::name_table
  46
  47 PPU_CTRL1_EMPH              .equ    mask ppu_ctrl1::emph
  48 PPU_CTRL1_SPRITE_VISIBLE    .equ    mask ppu_ctrl1::sprite_on
  49 PPU_CTRL1_BG_VISIBLE        .equ    mask ppu_ctrl1::bg_on
  50 PPU_CTRL1_SPRITE_CLIP       .equ    mask ppu_ctrl1::sprite_clip
  51 PPU_CTRL1_BG_CLIP           .equ    mask ppu_ctrl1::bg_clip
  52 PPU_CTRL1_MONO              .equ    mask ppu_ctrl1::mono
  53
  54 PPU_STATUS_VBLANK           .equ    mask ppu_status::vblank
  55 PPU_STATUS_SPRITE0          .equ    mask ppu_status::sprite0
  56 PPU_STATUS_SPRITE_OVERFLOW  .equ    mask ppu_status::sprite_overflow
  57
  58 ; Bitmasks that can be OR'ed together to create PPU_CTRL0_REG-compatible value.
  59 PPU_CTRL0_NMI_ON            .equ    PPU_CTRL0_NMI
  60 PPU_CTRL0_NMI_OFF           .equ    0
  61 PPU_CTRL0_SPRITE_SIZE_8x8   .equ    0
  62 PPU_CTRL0_SPRITE_SIZE_8x16  .equ    PPU_CTRL0_SPRITE_SIZE
  63 PPU_CTRL0_BG_TABLE_0000     .equ    0
  64 PPU_CTRL0_BG_TABLE_1000     .equ    PPU_CTRL0_BG_TABLE
  65 PPU_CTRL0_SPRITE_TABLE_0000 .equ    0
  66 PPU_CTRL0_SPRITE_TABLE_1000 .equ    PPU_CTRL0_SPRITE_TABLE
  67 PPU_CTRL0_PPU_ADDR_INC_1    .equ    0
  68 PPU_CTRL0_PPU_ADDR_INC_32   .equ    PPU_CTRL0_PPU_ADDR_INC
  69
  70 ; Bitmasks that can be OR'ed together to create PPU_CTRL1_REG-compatible value.
  71 PPU_CTRL1_SPRITE_ON         .equ    PPU_CTRL1_SPRITE_VISIBLE
  72 PPU_CTRL1_SPRITE_OFF        .equ    0
  73 PPU_CTRL1_BG_ON             .equ    PPU_CTRL1_BG_VISIBLE
  74 PPU_CTRL1_BG_OFF            .equ    0
  75 PPU_CTRL1_SPRITE_CLIP_ON    .equ    PPU_CTRL1_SPRITE_CLIP
  76 PPU_CTRL1_SPRITE_CLIP_OFF   .equ    0
  77 PPU_CTRL1_BG_CLIP_ON        .equ    PPU_CTRL1_BG_CLIP
  78 PPU_CTRL1_BG_CLIP_OFF       .equ    0
  79
  80 ; PPU state.
  81 .struc ppu_state
  82 ctrl0       .ppu_ctrl0
  83 ctrl1       .ppu_ctrl1
  84 scroll_x    .byte
  85 scroll_y    .byte
  86 .ends
  87
  88 ; Exported symbols.
  89 .extrn reset_screen:proc
  90 .extrn screen_on:proc
  91 .extrn screen_off:proc
  92 .extrn nmi_on:proc
  93 .extrn nmi_off:proc
  94 .extrn fill_nametable:proc
  95 .extrn fill_nametable_0_0:proc
  96 .extrn fill_all_nametables:proc
  97 .extrn get_scroll_xy:proc
  98 .extrn set_scroll_xy:proc
  99 .extrn write_ppu_data_at:label
 100 .extrn copy_string_to_ppu_buffer:proc
 101 .extrn copy_bytes_to_ppu_buffer:proc
 102
 103 .extrn ppu:ppu_state
 104
 105 .endif  ; !PPU_H