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NESHawk: clean up and implement DMC glitch

This commit is contained in:
alyosha-tas 2021-12-26 19:37:20 -05:00
parent d21f099567
commit 638c759aa0
3 changed files with 25 additions and 18 deletions
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4
src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/APU.cs
View File

@ -751,7 +751,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
if (fill_glitch_2)
{
// this will only run for one cycle and not actually run a DMA
Console.WriteLine("fill glitch 2");
//Console.WriteLine("fill glitch 2");
apu.dmc_dma_countdown = 4;
apu.DMC_RDY_check = -1;
}
@ -777,7 +777,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
else
{
// if refill and empty happen simultaneously, do not do another refill and act as though the sample buffer was filled
Console.WriteLine("fill glitch");
//Console.WriteLine("fill glitch");
sample_buffer_filled = true;
fill_glitch = false;
}

36
src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.Core.cs
View File

@ -522,7 +522,14 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
if (apu.dmc_dma_countdown == 0)
{
reread_trigger = true;
do_the_reread_2002++;
do_the_reread_2007++;
// if the DMA address has the same bits set as the re-read address, they don't occur
// TODO: need to check if also true for ppu regs
/*
if ((apu.dmc.sample_address & 0x2007) != 0x2002)
{
do_the_reread_2002++;
@ -532,7 +539,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
{
do_the_reread_2007++;
}
*/
if ((apu.dmc.sample_address & 0x401F) != 0x4016)
{
do_the_reread_cont_1++;
@ -567,22 +574,12 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
}
}
/*
if ((apu.dmc.timer == 3) && (apu.dmc.out_bits_remaining == 0) && (apu.dmc.sample_length == 0))
if ((apu.dmc.timer == 4) && (apu.dmc.out_bits_remaining == 0) && (apu.dmc.sample_length == 0))
{
//Console.WriteLine("close 2 " + cpu.TotalExecutedCycles + " " + apu.dmc.timer + " " + apu.dmc.sample_length + " " + cpu.opcode + " " + cpu.mi);
//apu.dmc.fill_glitch_2 = true;
apu.dmc.fill_glitch_2 = true;
}
*/
}
/*
if (apu.dmc.fill_glitch_2 && (apu.dmc_dma_countdown == 3))
{
apu.dmc_dma_countdown = -1;
dmc_dma_exec = false;
apu.dmc.fill_glitch_2 = false;
}
*/
}
/////////////////////////////
@ -611,6 +608,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
OAM_just_started = false;
DMC_just_started = false;
// DMC was started in the APU, but in this case it only lasts 1 cycle and is then aborted, so put this here
// TODO: should this clock controllers?
if (apu.dmc.fill_glitch_2)
{
apu.dmc_dma_countdown = -1;
dmc_dma_exec = false;
apu.dmc.fill_glitch_2 = false;
}
}
cpu.ExecuteOne();
@ -691,7 +697,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
// special hardware glitch case
ret_spec = read_joyport(addr);
if (reread_trigger && (do_the_reread_cont_1 == 0)) { Console.WriteLine("same 1 " + (apu.dmc.sample_address - 1)); }
//if (reread_trigger && (do_the_reread_cont_1 == 0)) { Console.WriteLine("same 1 " + (apu.dmc.sample_address - 1)); }
if ((reread_opp_4017 > 0) && ppu.region == PPU.Region.NTSC)
{
@ -725,7 +731,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
// special hardware glitch case
ret_spec = read_joyport(addr);
if (reread_trigger && (do_the_reread_cont_2 == 0)) { Console.WriteLine("same 2 " + (apu.dmc.sample_address - 1)); }
//if (reread_trigger && (do_the_reread_cont_2 == 0)) { Console.WriteLine("same 2 " + (apu.dmc.sample_address - 1)); }
if ((reread_opp_4016 > 0) && ppu.region == PPU.Region.NTSC)
{

3
src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/PPU.regs.cs
View File

@ -345,12 +345,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
private byte read_2002()
{
byte ret = peek_2002();
/*
if (nes.do_the_reread_2002 > 0)
{
if (Reg2002_vblank_active || Reg2002_vblank_active_pending)
Console.WriteLine("reread 2002");
}
*/
// reading from $2002 resets the destination for $2005 and $2006 writes
vtoggle = false;