diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/APU.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/APU.cs
index d03264872f..3e00eec2cb 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/APU.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/APU.cs
@@ -660,7 +660,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
public DMCUnit(APU apu, bool pal)
{
this.apu = apu;
- this.nes = apu.nes;
+ nes = apu.nes;
out_silence = true;
DMC_RATE = pal ? DMC_RATE_PAL : DMC_RATE_NTSC;
timer_reload = DMC_RATE[0];
@@ -668,26 +668,28 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
sample_buffer_filled = false;
out_deltacounter = 64;
out_bits_remaining = 7; //confirmed in VisualNES
- user_address = 0x8000; // even though this can't be accessed by writing, it is indeed the power up address
+ user_address = 0xC000; // even though this can't be accessed by writing, it is indeed the power up address
+ sample_address = 0xC000;
user_length = 1;
}
private bool irq_enabled;
private bool loop_flag;
- private int timer_reload;
+ public int timer_reload;
// dmc delay per visual 2a03
- private int delay;
+ public int delay;
// this timer never stops, ever, so it is convenient to use for even/odd timing used elsewhere
public int timer;
private int user_address;
public uint user_length, sample_length;
- private int sample_address, sample_buffer;
+ public int sample_address, sample_buffer;
private bool sample_buffer_filled;
- private int out_shift, out_bits_remaining, out_deltacounter;
+ public int out_shift, out_bits_remaining, out_deltacounter;
private bool out_silence;
+ public bool fill_glitch;
public int sample => out_deltacounter /* - 64*/;
@@ -711,6 +713,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
ser.Sync(nameof(out_bits_remaining), ref out_bits_remaining);
ser.Sync(nameof(out_deltacounter), ref out_deltacounter);
ser.Sync(nameof(out_silence), ref out_silence);
+ ser.Sync(nameof(fill_glitch), ref fill_glitch);
ser.Sync(nameof(delay), ref delay);
@@ -729,15 +732,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
// Any time the sample buffer is in an empty state and bytes remaining is not zero, the following occur:
// also note that the halt for DMC DMA occurs on APU cycles only (hence the timer check)
- if (!sample_buffer_filled && sample_length > 0 && apu.dmc_dma_countdown == -1 && delay==0)
+ if (!sample_buffer_filled && sample_length > 0 && apu.dmc_dma_countdown == -1 && delay==0)
{
if (!apu.call_from_write)
{
// when called due to empty bueffer while DMC running, there is no delay
- delay = 0;
+ //delay = 1;
nes.cpu.RDY = false;
nes.dmc_dma_exec = true;
- apu.dmc_dma_countdown = 3; // 3 here but this actually stops 4 cpu cycles because it starts before the cpu is run
+ apu.dmc_dma_countdown = 3;
apu.DMC_RDY_check = 2;
}
else
@@ -750,7 +753,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
else
{
delay = 3;
- }
+ }
}
}
@@ -762,7 +765,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
delay--;
if (delay == 0)
{
- if (!apu.call_from_write)
+ if (fill_glitch)
+ {
+ //fill_glitch = false;
+ apu.dmc_dma_countdown = 1;
+ apu.DMC_RDY_check = -1;
+ }
+ else if (!apu.call_from_write)
{
apu.dmc_dma_countdown = 4;
apu.DMC_RDY_check = 2;
@@ -825,11 +834,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
public void set_lenctr_en(bool en)
{
- if (!en)
+ // should this be delayed by two/three cycles?
+
+ if(!en)
{
// If the DMC bit is clear, the DMC bytes remaining will be set to 0
// and the DMC will silence when it empties.
- sample_length = 0;
+ sample_length = 0;
}
else
{
@@ -892,6 +903,9 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
sample_buffer = apu.nes.ReadMemory((ushort)sample_address);
sample_buffer_filled = true;
sample_address = (ushort)(sample_address + 1);
+
+ //sample address wraps to 0xC000
+ if (sample_address == 0) { sample_address = 0xC000;}
// Console.WriteLine(sample_length);
// Console.WriteLine(user_length);
sample_length--;
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.Core.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.Core.cs
index c657f0e41d..769503c9d7 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.Core.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.Core.cs
@@ -442,7 +442,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
public bool dmc_realign;
public bool IRQ_delay;
public bool special_case_delay; // very ugly but the only option
- public bool do_the_reread;
+ public bool reread_trigger;
+ public int do_the_reread_2002, do_the_reread_2007, do_the_reread_cont_1, do_the_reread_cont_2;
public byte DB; //old data bus values from previous reads
internal void RunCpuOne()
@@ -489,7 +490,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
if (apu.dmc_dma_countdown > 0)
{
- if (apu.dmc_dma_countdown == 1)
+ if (apu.dmc_dma_countdown == 1 && !apu.dmc.fill_glitch)
{
dmc_realign = true;
}
@@ -507,14 +508,47 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
apu.dmc_dma_countdown--;
if (apu.dmc_dma_countdown == 0)
{
- apu.RunDMCFetch();
+ if (!apu.dmc.fill_glitch)
+ {
+ reread_trigger = true;
+ // if the DMA address has the same bits set as the re-read address, they don't occur
+ if ((apu.dmc.sample_address & 0x2007) != 0x2002)
+ {
+ do_the_reread_2002++;
+ }
+
+ if ((apu.dmc.sample_address & 0x2007) != 0x2007)
+ {
+ do_the_reread_2007++;
+ }
+
+ if ((apu.dmc.sample_address & 0x401F) != 0x4016)
+ {
+ do_the_reread_cont_1++;
+ }
+
+ if ((apu.dmc.sample_address & 0x401F) != 0x4017)
+ {
+ do_the_reread_cont_2++;
+ }
+
+ apu.RunDMCFetch();
+ }
+
dmc_dma_exec = false;
apu.dmc_dma_countdown = -1;
- do_the_reread = true;
-
- //Console.WriteLine("dmc RDY false " + cpu.TotalExecutedCycles + " " + (apu.dmc.timer & 1));
- }
- //Console.WriteLine("dmc RDY false " + cpu.TotalExecutedCycles + " " + cpu.opcode + " " + cpu.mi + " " + apu.dmc_dma_countdown);
+ apu.dmc.fill_glitch = false;
+ /*
+ //if (apu.dmc.timer == (apu.dmc.timer_reload-0) && apu.dmc.out_bits_remaining == 7)
+ //if (apu.dmc.timer == 2 && apu.dmc.out_bits_remaining == 0)
+ {
+ Console.WriteLine("close " + cpu.TotalExecutedCycles + " " + apu.dmc.timer + " " + apu.dmc.sample_length);
+ apu.dmc.fill_glitch = true;
+ apu.dmc.delay = 3;
+ }
+ */
+ //Console.WriteLine("dmc RDY false " + cpu.TotalExecutedCycles + " " + cpu.opcode + " " + cpu.mi + " " + apu.dmc.timer);
+ }
}
/////////////////////////////
@@ -528,7 +562,9 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
}
else if (special_case_delay || apu.dmc_dma_countdown == 3)
{
+
cpu.IRQ = _irq_apu || Board.IrqSignal;
+ //if (cpu.IRQ) { Console.WriteLine("something IRQ"); }
special_case_delay = false;
}
@@ -546,8 +582,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
apu.RunOneLast();
- if (do_the_reread && cpu.RDY)
- do_the_reread = false;
+ if (reread_trigger && cpu.RDY)
+ {
+ do_the_reread_2002 = 0;
+ do_the_reread_2007 = 0;
+ do_the_reread_cont_1 = 0;
+ do_the_reread_cont_2 = 0;
+ reread_trigger = false;
+ }
+
IRQ_delay = false;
@@ -602,11 +645,14 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
// special hardware glitch case
ret_spec = read_joyport(addr);
- if (do_the_reread && ppu.region==PPU.Region.NTSC)
+ //if (reread_trigger && (do_the_reread_cont_1 == 0)) { Console.WriteLine("same 1 " + (apu.dmc.sample_address - 1)); }
+
+ if ((do_the_reread_cont_1 > 0) && ppu.region==PPU.Region.NTSC)
{
ret_spec = read_joyport(addr);
- do_the_reread = false;
- Console.WriteLine("DMC glitch player 1 ");
+ do_the_reread_cont_1--;
+ if (do_the_reread_cont_1 > 0) { ret_spec = read_joyport(addr); }
+ //Console.WriteLine("DMC glitch player 1 " + cpu.TotalExecutedCycles + " addr " + (apu.dmc.sample_address - 1));
}
return ret_spec;
@@ -626,12 +672,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
{
// special hardware glitch case
ret_spec = read_joyport(addr);
- if (do_the_reread && ppu.region == PPU.Region.NTSC)
+
+ //if (reread_trigger && (do_the_reread_cont_2 == 0)) { Console.WriteLine("same 2 " + (apu.dmc.sample_address - 1)); }
+
+ if ((do_the_reread_cont_2 > 0) && ppu.region == PPU.Region.NTSC)
{
ret_spec = read_joyport(addr);
- do_the_reread = false;
- Console.WriteLine("DMC glitch player 2");
+ do_the_reread_cont_2--;
+ if (do_the_reread_cont_2 > 0) { ret_spec = read_joyport(addr); }
+ //Console.WriteLine("DMC glitch player 2 " + cpu.TotalExecutedCycles + " addr " + (apu.dmc.sample_address - 1));
}
+
return ret_spec;
}
default:
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IStatable.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IStatable.cs
index f3c0d2f973..ff198a874c 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IStatable.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IStatable.cs
@@ -31,7 +31,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
ser.Sync(nameof(dmc_realign), ref dmc_realign);
ser.Sync(nameof(IRQ_delay), ref IRQ_delay);
ser.Sync(nameof(special_case_delay), ref special_case_delay);
- ser.Sync(nameof(do_the_reread), ref do_the_reread);
+ ser.Sync(nameof(reread_trigger), ref reread_trigger);
+ ser.Sync(nameof(do_the_reread_2002), ref do_the_reread_2002);
+ ser.Sync(nameof(do_the_reread_2007), ref do_the_reread_2007);
+ ser.Sync(nameof(do_the_reread_cont_1), ref do_the_reread_cont_1);
+ ser.Sync(nameof(do_the_reread_cont_2), ref do_the_reread_cont_2);
// VS related
ser.Sync("VS", ref _isVS);
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/PPU.regs.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/PPU.regs.cs
index b0489acbff..27be45d8ce 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/PPU.regs.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/PPU.regs.cs
@@ -345,12 +345,24 @@ 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;
Reg2002_vblank_active = 0;
Reg2002_vblank_active_pending = false;
+ if (nes.do_the_reread_2002 > 0)
+ {
+ ret = peek_2002();
+ // could be another reread, but no other side effects, so don't bother
+ }
+
// update the open bus here
ppu_open_bus = ret;
PpuOpenBusDecay(DecayType.High);
@@ -679,11 +691,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
double_2007_read = nes.cpu.TotalExecutedCycles + 1;
}
- if (nes.do_the_reread)
+ if (nes.do_the_reread_2007 > 0)
{
ret_spec = read_2007();
ret_spec = read_2007();
- nes.do_the_reread = false;
+ // always 2?
}
return ret_spec;
}