using Codice.CM.Client.Differences; using System; namespace VirtualNes.Core { public class APU_MMC5 : APU_INTERFACE { public const int RECTANGLE_VOL_SHIFT = 8; public const int DAOUT_VOL_SHIFT = 6; SYNCRECTANGLE sch0 = new SYNCRECTANGLE(); SYNCRECTANGLE sch1 = new SYNCRECTANGLE(); RECTANGLE ch0 = new RECTANGLE(); RECTANGLE ch1 = new RECTANGLE(); byte reg5010; byte reg5011; byte reg5015; byte sync_reg5015; int FrameCycle; float cpu_clock; int cycle_rate; // Tables static int[] vbl_length = new int[32]; static int[] duty_lut = new int[4]; static int[] decay_lut = new int[16]; static int[] vbl_lut = new int[32]; public APU_MMC5() { // 仮設定 Reset(APU_INTERFACE.APU_CLOCK, 22050); } public override void Reset(float fClock, int nRate) { sch0.ZeroMemory(); sch1.ZeroMemory(); reg5010 = reg5011 = reg5015 = 0; sync_reg5015 = 0; FrameCycle = 0; Setup(fClock, nRate); for (ushort addr = 0x5000; addr <= 0x5015; addr++) { Write(addr, 0); } } public override void Setup(float fClock, int nRate) { cpu_clock = fClock; cycle_rate = (int)(fClock * 65536.0f / nRate); // Create Tables int i; int samples = (int)(nRate / 60.0f); for (i = 0; i < 16; i++) decay_lut[i] = (i + 1) * samples * 5; for (i = 0; i < 32; i++) vbl_lut[i] = vbl_length[i] * samples * 5; } public override void Write(ushort addr, byte data) { switch (addr) { // MMC5 CH0 rectangle case 0x5000: ch0.reg[0] = data; ch0.volume = (byte)(data & 0x0F); ch0.holdnote = (byte)(data & 0x20); ch0.fixed_envelope = (byte)(data & 0x10); ch0.env_decay = decay_lut[data & 0x0F]; ch0.duty_flip = duty_lut[data >> 6]; break; case 0x5001: ch0.reg[1] = data; break; case 0x5002: ch0.reg[2] = data; ch0.freq = INT2FIX(((ch0.reg[3] & 0x07) << 8) + data + 1); break; case 0x5003: ch0.reg[3] = data; ch0.vbl_length = vbl_lut[data >> 3]; ch0.env_vol = 0; ch0.freq = INT2FIX(((data & 0x07) << 8) + ch0.reg[2] + 1); if ((reg5015 & 0x01) != 0) ch0.enable = 0xFF; break; // MMC5 CH1 rectangle case 0x5004: ch1.reg[0] = data; ch1.volume = (byte)(data & 0x0F); ch1.holdnote = (byte)(data & 0x20); ch1.fixed_envelope = (byte)(data & 0x10); ch1.env_decay = decay_lut[data & 0x0F]; ch1.duty_flip = duty_lut[data >> 6]; break; case 0x5005: ch1.reg[1] = data; break; case 0x5006: ch1.reg[2] = data; ch1.freq = INT2FIX(((ch1.reg[3] & 0x07) << 8) + data + 1); break; case 0x5007: ch1.reg[3] = data; ch1.vbl_length = vbl_lut[data >> 3]; ch1.env_vol = 0; ch1.freq = INT2FIX(((data & 0x07) << 8) + ch1.reg[2] + 1); if ((reg5015 & 0x02) != 0) ch1.enable = 0xFF; break; case 0x5010: reg5010 = data; break; case 0x5011: reg5011 = data; break; case 0x5012: case 0x5013: case 0x5014: break; case 0x5015: reg5015 = data; if ((reg5015 & 0x01) != 0) { ch0.enable = 0xFF; } else { ch0.enable = 0; ch0.vbl_length = 0; } if ((reg5015 & 0x02) != 0) { ch1.enable = 0xFF; } else { ch1.enable = 0; ch1.vbl_length = 0; } break; } } internal void SyncWrite(ushort addr, byte data) { switch (addr) { // MMC5 CH0 rectangle case 0x5000: sch0.reg[0] = data; sch0.holdnote = (byte)(data & 0x20); break; case 0x5001: case 0x5002: sch0.reg[addr & 3] = data; break; case 0x5003: sch0.reg[3] = data; sch0.vbl_length = vbl_length[data >> 3]; if ((sync_reg5015 & 0x01) != 0) sch0.enable = 0xFF; break; // MMC5 CH1 rectangle case 0x5004: sch1.reg[0] = data; sch1.holdnote = (byte)(data & 0x20); break; case 0x5005: case 0x5006: sch1.reg[addr & 3] = data; break; case 0x5007: sch1.reg[3] = data; sch1.vbl_length = vbl_length[data >> 3]; if ((sync_reg5015 & 0x02) != 0) sch1.enable = 0xFF; break; case 0x5010: case 0x5011: case 0x5012: case 0x5013: case 0x5014: break; case 0x5015: sync_reg5015 = data; if ((sync_reg5015 & 0x01) != 0) { sch0.enable = 0xFF; } else { sch0.enable = 0; sch0.vbl_length = 0; } if ((sync_reg5015 & 0x02) != 0) { sch1.enable = 0xFF; } else { sch1.enable = 0; sch1.vbl_length = 0; } break; } } internal byte SyncRead(ushort addr) { byte data = 0; if (addr == 0x5015) { if ((sch0.enable != 0) && sch0.vbl_length > 0) data |= (1 << 0); if ((sch1.enable != 0) && sch1.vbl_length > 0) data |= (1 << 1); } return data; } public override bool Sync(int cycles) { FrameCycle += cycles; if (FrameCycle >= 7457 * 5 / 2) { FrameCycle -= 7457 * 5 / 2; if (sch0.enable != 0 && sch0.holdnote == 0) { if ((sch0.vbl_length) != 0) { sch0.vbl_length--; } } if (sch1.enable != 0 && sch1.holdnote == 0) { if ((sch1.vbl_length) != 0) { sch1.vbl_length--; } } } return false; } public override int Process(int channel) { switch (channel) { case 0: return RectangleRender(ch0); case 1: return RectangleRender(ch1); case 2: return reg5011 << DAOUT_VOL_SHIFT; } return 0; } public override int GetFreq(int channel) { if (channel == 0 || channel == 1) { RECTANGLE ch = null; if (channel == 0) ch = ch0; else ch = ch1; if (ch.enable == 0 || ch.vbl_length <= 0) return 0; if (ch.freq < INT2FIX(8)) return 0; if (ch.fixed_envelope != 0) { if (ch.volume == 0) return 0; } else { if ((0x0F - ch.env_vol) == 0) return 0; } return (int)(256.0f * cpu_clock / (FIX2INT(ch.freq) * 16.0f)); } return 0; } private int RectangleRender(RECTANGLE ch) { if (ch.enable == 0 || ch.vbl_length <= 0) return 0; // vbl length counter if (ch.holdnote == 0) ch.vbl_length -= 5; // envelope unit ch.env_phase -= 5 * 4; while (ch.env_phase < 0) { ch.env_phase += ch.env_decay; if ((ch.holdnote) != 0) ch.env_vol = (byte)((ch.env_vol + 1) & 0x0F); else if (ch.env_vol < 0x0F) ch.env_vol++; } if (ch.freq < INT2FIX(8)) return 0; int volume; if ((ch.fixed_envelope) != 0) volume = ch.volume; else volume = (0x0F - ch.env_vol); int output = volume << RECTANGLE_VOL_SHIFT; ch.phaseacc -= cycle_rate; if (ch.phaseacc >= 0) { if (ch.adder < ch.duty_flip) ch.output_vol = output; else ch.output_vol = -output; return ch.output_vol; } if (ch.freq > cycle_rate) { ch.phaseacc += ch.freq; ch.adder = (ch.adder + 1) & 0x0F; if (ch.adder < ch.duty_flip) ch.output_vol = output; else ch.output_vol = -output; } else { // 加重平均 int num_times, total; num_times = total = 0; while (ch.phaseacc < 0) { ch.phaseacc += ch.freq; ch.adder = (ch.adder + 1) & 0x0F; if (ch.adder < ch.duty_flip) total += output; else total -= output; num_times++; } ch.output_vol = total / num_times; } return ch.output_vol; } public class SYNCRECTANGLE { // For sync public byte[] reg = new byte[4]; public byte enable; public byte holdnote; public byte[] dummy = new byte[2]; public int vbl_length; public void ZeroMemory() { Array.Clear(reg, 0, reg.Length); enable = 0; holdnote = 0; Array.Clear(dummy, 0, dummy.Length); vbl_length = 0; } } public class RECTANGLE { public byte[] reg = new byte[4]; public byte enable; public int vbl_length; public int phaseacc; public int freq; public int output_vol; public byte fixed_envelope; public byte holdnote; public byte volume; public byte env_vol; public int env_phase; public int env_decay; public int adder; public int duty_flip; } } }