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

nes-fix #12 "Strange "White noise" sound during 1943 (USA) intro" as well as a boatload of aesthetic improvements to make the sound output not so embarassing. no speedups whatsoever though.

This commit is contained in:
zeromus 2012-07-15 00:09:34 +00:00
parent 1f588c451f
commit a47c70d0ef
1 changed files with 94 additions and 60 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

154
BizHawk.Emulation/Consoles/Nintendo/NES/APU.cs
View File

@ -1,4 +1,6 @@
using System;
//TODO - so many integers in the square wave output keep us from exactly unbiasing the waveform. also other waves probably
using System;
using System.IO;
using System.Collections.Generic;
@ -11,6 +13,7 @@ using BizHawk.Emulation.Sound;
//TODO - refactor length counter to be separate component
namespace BizHawk.Emulation.Consoles.Nintendo
{
@ -233,19 +236,21 @@ namespace BizHawk.Emulation.Consoles.Nintendo
//reload timer
timer_counter = timer_raw_reload_value;
}
if (duty_value) //we are outputting something
if (duty_value) //high state of duty cycle
{
sample = env_output;
if (swp_silence)
sample = 0;
sample = env_output / 2; //(a little biasing hack here)
if (len_cnt == 0) //length counter is 0
sample = 0; //silenced
sample = env_output / 2; //silenced (a little biasing hack here)
}
else
sample = 0; //duty cycle is 0, silenced.
sample = env_output / 2; //duty cycle is 0, silenced.
sample -= env_output / 2; //unbias
}
}
@ -383,9 +388,10 @@ namespace BizHawk.Emulation.Consoles.Nintendo
noise_bit = (shift_register & 1) != 0;
}
if (noise_bit || len_cnt == 0) sample = 0;
else
sample = env_output;
//unbiasing is rolled in here
if (len_cnt == 0) sample = 0;
else if (noise_bit) sample = -env_output;
else sample = env_output;
}
}
@ -476,10 +482,17 @@ namespace BizHawk.Emulation.Consoles.Nintendo
seq = (seq + 1) & 0x1F;
timer = timer_cnt_reload;
}
//if(CFG_DECLICK)
//sample = TRIANGLE_TABLE[(seq+8)&0x1F];
//else
sample = TRIANGLE_TABLE[seq];
if(CFG_DECLICK)
sample = TRIANGLE_TABLE[(seq+8)&0x1F];
else
sample = TRIANGLE_TABLE[seq];
//special hack: frequently, games will use the maximum frequency triangle in order to mute it
//apparently this results in the DAC for the triangle wave outputting a steady level at about 7.5
//so we'll emulate it at the digital level
if (timer_cnt_reload == 1) sample = 8;
sample -= 8; //unbias
}
}
@ -576,12 +589,21 @@ namespace BizHawk.Emulation.Consoles.Nintendo
timer = timer_reload;
Clock();
}
if (out_silence)
sample = 0;
else
{
sample = out_deltacounter;
sample -= 64; //unbias;
}
}
void SyncSample()
{
sample = (out_deltacounter - 64) / 4;
//sample = (out_deltacounter - 64) / 4;
//Console.WriteLine("dmc sample: {0}", sample);
//sample -= 64; //unbias
}
void Clock()
@ -844,54 +866,47 @@ namespace BizHawk.Emulation.Consoles.Nintendo
void _WriteReg(int addr, byte val)
{
//Console.WriteLine("{0:X4} = {1:X2}", addr, val);
switch (addr)
int index = addr - 0x4000;
int reg = index & 3;
int channel = index >> 2;
switch (channel)
{
case 0x4000:
case 0x4001:
case 0x4002:
case 0x4003:
pulse[0].WriteReg(addr - 0x4000, val);
case 0:
pulse[0].WriteReg(reg, val);
break;
case 0x4004:
case 0x4005:
case 0x4006:
case 0x4007:
pulse[1].WriteReg(addr - 0x4004, val);
case 1:
pulse[1].WriteReg(reg, val);
break;
case 0x4008:
case 0x4009:
case 0x400A:
case 0x400B:
triangle.WriteReg(addr - 0x4008, val);
case 2:
triangle.WriteReg(reg, val);
break;
case 0x400C:
case 0x400D:
case 0x400E:
case 0x400F:
noise.WriteReg(addr - 0x400C, val);
case 3:
noise.WriteReg(reg, val);
break;
case 0x4010:
case 0x4011:
case 0x4012:
case 0x4013:
dmc.WriteReg(addr - 0x4010, val);
case 4:
dmc.WriteReg(reg, val);
break;
case 0x4015:
pulse[0].set_lenctr_en(val & 1);
pulse[1].set_lenctr_en((val >> 1) & 1);
triangle.set_lenctr_en((val >> 2) & 1);
noise.set_lenctr_en((val >> 3) & 1);
dmc.set_lenctr_en(val.Bit(4));
break;
case 0x4017:
//Console.WriteLine("apu 4017 = {0:X2}", val);
sequencer_mode = (val >> 7) & 1;
sequencer_irq_inhibit = (val >> 6) & 1;
if (sequencer_irq_inhibit == 1)
case 5:
if (addr == 0x4015)
{
sequencer_irq_clear_pending = true;
pulse[0].set_lenctr_en(val & 1);
pulse[1].set_lenctr_en((val >> 1) & 1);
triangle.set_lenctr_en((val >> 2) & 1);
noise.set_lenctr_en((val >> 3) & 1);
dmc.set_lenctr_en(val.Bit(4));
}
else if (addr == 0x4017)
{
//Console.WriteLine("apu 4017 = {0:X2}", val);
sequencer_mode = (val >> 7) & 1;
sequencer_irq_inhibit = (val >> 6) & 1;
if (sequencer_irq_inhibit == 1)
{
sequencer_irq_clear_pending = true;
}
sequence_reset_pending = true;
break;
}
sequence_reset_pending = true;
break;
}
}
@ -935,12 +950,31 @@ namespace BizHawk.Emulation.Consoles.Nintendo
noise.Run();
dmc.Run();
int mix = 0;
if (EnableSquare1) mix += pulse[0].sample;
if (EnableSquare2) mix += pulse[1].sample;
if (EnableTriangle) mix += triangle.sample;
if (EnableNoise) mix += noise.sample >> 1;
if (EnableDMC) mix += dmc.sample;
int s_pulse0 = pulse[0].sample;
int s_pulse1 = pulse[1].sample;
int s_tri = triangle.sample;
int s_noise = noise.sample;
int s_dmc = dmc.sample;
//int s_ext = 0; //gamepak
if (!EnableSquare1) s_pulse0 = 0;
if (!EnableSquare2) s_pulse1 = 0;
if (!EnableTriangle) s_tri = 0;
if (!EnableNoise) s_noise = 0;
if (!EnableDMC) s_dmc = 0;
//s_pulse0 = 0;
//s_pulse1 = 0;
//s_tri = 0;
//s_noise = 0;
//s_dmc = 0;
const float NOISEADJUST = 0.5f;
float pulse_out = 0.00752f * (s_pulse0 + s_pulse1);
float tnd_out = 0.00851f * s_tri + 0.00494f * NOISEADJUST * s_noise + 0.00335f * s_dmc;
float output = pulse_out + tnd_out;
int mix = (int)(50000 * output);
EmitSample(mix);
@ -1011,7 +1045,7 @@ namespace BizHawk.Emulation.Consoles.Nintendo
double factional_remainder = (this_samp - last_hwsamp) * (1 - ratio);
accumulate += fractional;
accumulate *= 436; //32768/(15*4) -- adjust later for other sound channels
//accumulate *= 436; //32768/(15*4) -- adjust later for other sound channels
int outsamp = (int)(accumulate / kInvMixRate);
if (CFG_USE_METASPU)
metaspu.buffer.enqueue_sample((short)outsamp, (short)outsamp);