ShuriZma
/
BizHawk
mirror of https://github.com/TASEmulators/BizHawk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Add files via upload

This commit is contained in:
alyosha-tas 2017-09-06 19:38:18 -04:00 committed by GitHub
parent f0306c10df
commit 465d1ea3a1
2 changed files with 185 additions and 80 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/MemoryMap.cs
View File

@ -49,15 +49,18 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
}
else if (addr < 0x9800)
{
return CHR_RAM[addr - 0x8000];
if (ppu.VRAM_access_read) { return CHR_RAM[addr - 0x8000]; }
else { return 0xFF; }
}
else if (addr < 0x9C00)
{
return BG_map_1[addr - 0x9800];
if (ppu.VRAM_access_read) { return BG_map_1[addr - 0x9800]; }
else { return 0xFF; }
}
else if (addr < 0xA000)
{
return BG_map_2[addr - 0x9C00];
if (ppu.VRAM_access_read) { return BG_map_2[addr - 0x9C00]; }
else { return 0xFF; }
}
else if (addr < 0xC000)
{
@ -71,9 +74,10 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
{
return RAM[addr - 0xE000];
}
else if (addr < 0xFEA0 && ppu.OAM_access)
else if (addr < 0xFEA0)
{
return OAM[addr - 0xFE00];
if (ppu.OAM_access_read) { return OAM[addr - 0xFE00]; }
else { return 0xFF; }
}
else if (addr < 0xFF00)
{
@ -117,15 +121,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
}
else if (addr < 0x9800)
{
CHR_RAM[addr - 0x8000] = value;
if (ppu.VRAM_access_write) { CHR_RAM[addr - 0x8000] = value; }
}
else if (addr < 0x9C00)
{
BG_map_1[addr - 0x9800] = value;
if (ppu.VRAM_access_write) { BG_map_1[addr - 0x9800] = value; }
}
else if (addr < 0xA000)
{
BG_map_2[addr - 0x9C00] = value;
if (ppu.VRAM_access_write) { BG_map_2[addr - 0x9C00] = value; }
}
else if (addr < 0xC000)
{
@ -139,9 +143,9 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
{
RAM[addr - 0xE000] = value;
}
else if (addr < 0xFEA0 && ppu.OAM_access)
else if (addr < 0xFEA0)
{
OAM[addr - 0xFE00] = value;
if (ppu.OAM_access_write) { OAM[addr - 0xFE00] = value; }
}
else if (addr < 0xFF00)
{

241
BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/PPU.cs
View File

@ -39,15 +39,18 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
public bool LCD_was_off;
public bool stat_line;
public bool stat_line_old;
public bool hbl_set_once;
public int hbl_countdown;
// OAM scan
public bool OAM_access;
public bool OAM_access_read;
public bool OAM_access_write;
public int OAM_scan_index;
public int SL_sprites_index;
public int[] SL_sprites = new int[40];
public int write_sprite;
public bool no_scan;
// render
public bool VRAM_access;
public bool VRAM_access_read;
public bool VRAM_access_write;
public int read_case;
public int internal_cycle;
public int y_tile;
@ -166,7 +169,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
{
if (DMA_clock >= 4)
{
OAM_access = false;
OAM_access_read = false;
if ((DMA_clock % 4) == 1)
{
// the cpu can't access memory during this time, but we still need the ppu to be able to.
@ -194,13 +197,51 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
if (DMA_clock==648)
{
DMA_start = false;
OAM_access = true;
OAM_access_read = true;
}
}
// the ppu only does anything if it is turned on via bit 7 of LCDC
if (LCDC.Bit(7))
{
// start the next scanline
if (cycle == 456)
{
cycle = 0;
LY += LY_inc;
no_scan = false;
// here is where LY = LYC gets cleared (but only if LY isnt 0 as that's a special case
if (LY_inc == 1)
{
LYC_INT = false;
STAT &= 0xFB;
}
if (LY == 0 && LY_inc == 0)
{
LY_inc = 1;
Core.in_vblank = false;
VBL_INT = false;
// special note here, the y coordiate of the window is kept if the window is deactivated
// meaning it will pick up where it left off if re-enabled later
// so we don't reset it in the scanline loop
window_y_tile = 0;
window_y_tile_inc = 0;
window_started = false;
}
Core.cpu.LY = LY;
if (LY == 144)
{
Core.in_vblank = true;
}
}
// exit vblank if LCD went from off to on
if (LCD_was_off)
{
@ -211,6 +252,12 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
// we exit vblank into mode 0 for 4 cycles
// but no hblank interrupt, presumably this only happens transitioning from mode 3 to 0
STAT &= 0xFC;
// also the LCD doesn't turn on right away
// also, the LCD does not enter mode 2 on scanline 0 when first turned on
no_scan = true;
cycle = 8;
}
// the VBL stat is continuously asserted
@ -256,26 +303,88 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
if (!Core.in_vblank)
{
if (cycle == 4)
if (no_scan)
{
// here mode 2 will be set to true and interrupts fired if enabled
STAT &= 0xFC;
STAT |= 0x2;
if (STAT.Bit(5)) { OAM_INT = true; }
HBL_INT = false;
}
// timings are slightly different if we just turned on the LCD
// there is no mode 2 (presumably it missed the trigger)
// mode 3 is very short, probably in some self test mode before turning on?
if (cycle >= 4 && cycle < 84)
{
// here OAM scanning is performed
OAM_scan(cycle - 4);
if (cycle == 12)
{
LYC_INT = false;
STAT &= 0xFB;
if (LY == LYC)
{
// set STAT coincidence FLAG and interrupt flag if it is enabled
STAT |= 0x04;
if (STAT.Bit(6)) { LYC_INT = true; }
}
}
if (cycle == 84)
{
STAT &= 0xFC;
STAT |= 0x03;
OAM_INT = false;
OAM_access_read = false;
OAM_access_write = false;
VRAM_access_read = false;
VRAM_access_write = false;
}
if (cycle == 256)
{
STAT &= 0xFC;
OAM_INT = false;
if (STAT.Bit(3)) { HBL_INT = true; }
OAM_access_read = true;
OAM_access_write = true;
VRAM_access_read = true;
VRAM_access_write = true;
}
}
else if (cycle >= 84 && LY < 144)
else
{
// render the screen and handle hblank
render(cycle - 84);
if (cycle < 80)
{
if (cycle == 4)
{
// apparently, writes can make it to OAm one cycle longer then reads
OAM_access_write = false;
// here mode 2 will be set to true and interrupts fired if enabled
STAT &= 0xFC;
STAT |= 0x2;
if (STAT.Bit(5)) { OAM_INT = true; }
HBL_INT = false;
}
// here OAM scanning is performed
OAM_scan(cycle);
}
else if (cycle >= 80 && LY < 144)
{
if (cycle == 84)
{
STAT &= 0xFC;
STAT |= 0x03;
OAM_INT = false;
OAM_access_write = false;
VRAM_access_write = false;
}
// render the screen and handle hblank
render(cycle - 80);
}
}
}
@ -316,34 +425,6 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
}
cycle++;
if (cycle==456)
{
cycle = 0;
LY+=LY_inc;
if (LY==0 && LY_inc == 0)
{
LY_inc = 1;
Core.in_vblank = false;
VBL_INT = false;
// special note here, the y coordiate of the window is kept if the window is deactivated
// meaning it will pick up where it left off if re-enabled later
// so we don't reset it in the scanline loop
window_y_tile = 0;
window_y_tile_inc = 0;
window_started = false;
}
Core.cpu.LY = LY;
if (LY==144)
{
Core.in_vblank = true;
}
}
}
else
{
@ -391,7 +472,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
// TODO: maybe stat mode 2 flags are set at cycle 0 on visible scanlines?
if (OAM_cycle == 0)
{
OAM_access = false;
OAM_access_read = false;
OAM_scan_index = 0;
SL_sprites_index = 0;
write_sprite = 0;
@ -458,12 +540,10 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
// i.e. just keeping track of the lowest x-value sprite
if (render_cycle == 0)
{
STAT &= 0xFC;
STAT |= 0x03;
OAM_INT = false;
OAM_access_read = false;
OAM_access_write = true;
VRAM_access_read = false;
OAM_access = false;
VRAM_access = false;
OAM_scan_index = 0;
read_case = 0;
internal_cycle = 0;
@ -526,6 +606,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
}
window_x_tile = (int)Math.Floor((float)(pixel_counter - (window_x - 7)) / 8);
window_tile_inc = 0;
window_started = true;
}
@ -576,7 +657,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
int t_index = pixel_counter - (SL_sprites_ordered[i * 4] - 8);
t_index = 7 - t_index;
sprite_data[0] = (byte)((SL_sprites_ordered[i * 4 + 1] >> t_index) & 1);
sprite_data[1] = (byte)(((SL_sprites_ordered[i * 4 + 2] >> t_index) & 1) << 1);
@ -633,7 +714,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
if (pixel_counter == 160)
{
read_case = 8;
hbl_set_once = true;
hbl_countdown = 4;
}
}
render_counter++;
@ -772,7 +853,9 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
{
temp_fetch = window_y_tile * 32 + (window_x_tile + window_tile_inc) % 32;
tile_byte = LCDC.Bit(6) ? Core.BG_map_2[temp_fetch] : Core.BG_map_1[temp_fetch];
}
else
{
@ -859,19 +942,28 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
break;
case 8: // done reading, we are now in phase 0
OAM_access = true;
VRAM_access = true;
STAT &= 0xFC;
STAT |= 0x00;
pre_render = true;
if (hbl_set_once)
// the other interrupts appear to be delayed by 1 CPU cycle, so do the same here
if (hbl_countdown > 0)
{
if (STAT.Bit(3)) { HBL_INT = true; }
hbl_set_once = false;
hbl_countdown--;
if (hbl_countdown == 0)
{
STAT &= 0xFC;
STAT |= 0x00;
if (STAT.Bit(3)) { HBL_INT = true; }
OAM_access_read = true;
OAM_access_write = true;
VRAM_access_read = true;
VRAM_access_write = true;
}
}
break;
}
@ -942,6 +1034,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
window_y = 0;
window_x = 0;
LY_inc = 1;
no_scan = false;
OAM_access_read = true;
VRAM_access_read = true;
OAM_access_write = true;
VRAM_access_write = true;
cycle = 0;
LYC_INT = false;
@ -1043,15 +1140,19 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
ser.Sync("OAM_INT", ref OAM_INT);
ser.Sync("stat_line", ref stat_line);
ser.Sync("stat_line_old", ref stat_line_old);
ser.Sync("hbl_set_once", ref hbl_set_once);
ser.Sync("LCD_was_off", ref LCD_was_off);
ser.Sync("OAM_access", ref OAM_access);
ser.Sync("hbl_countdown", ref hbl_countdown);
ser.Sync("LCD_was_off", ref LCD_was_off);
ser.Sync("OAM_scan_index", ref OAM_scan_index);
ser.Sync("SL_sprites_index", ref SL_sprites_index);
ser.Sync("SL_sprites", ref SL_sprites, false);
ser.Sync("write_sprite", ref write_sprite);
ser.Sync("no_scan", ref no_scan);
ser.Sync("OAM_access_read", ref OAM_access_read);
ser.Sync("OAM_access_write", ref OAM_access_write);
ser.Sync("VRAM_access_read", ref VRAM_access_read);
ser.Sync("VRAM_access_write", ref VRAM_access_write);
ser.Sync("VRAM_access", ref VRAM_access);
ser.Sync("read_case", ref read_case);
ser.Sync("internal_cycle", ref internal_cycle);
ser.Sync("y_tile", ref y_tile);