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* [Qemu-devel] [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59
@ 2009-10-28 16:50 TAKEDA, toshiya
  2009-10-28 20:08 ` Stuart Brady
  0 siblings, 1 reply; 16+ messages in thread
From: TAKEDA, toshiya @ 2009-10-28 16:50 UTC (permalink / raw)
  To: qemu-devel

diff --git a/qemu/hw/ay8910.c b/qemu/hw/ay8910.c
new file mode 100644
index 0000000..d371023
--- /dev/null
+++ b/qemu/hw/ay8910.c
@@ -0,0 +1,733 @@
+/***************************************************************************
+
+  ay8910.c
+
+
+  Emulation of the AY-3-8910 / YM2149 sound chip.
+
+  Based on various code snippets by Ville Hallik, Michael Cuddy,
+  Tatsuyuki Satoh, Fabrice Frances, Nicola Salmoria.
+
+***************************************************************************/
+
+/* This version of ay8910.c is a fork of the MAME 0.59 one, relicensed under the LGPL.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include "ay8910.h"
+
+#define MAX_OUTPUT 0x7fff
+
+#define STEP 0x8000
+
+#define logerror(...)
+
+int ay8910_index_ym;
+static int num = 0, ym_num = 0;
+
+struct AY8910
+{
+	int SampleRate;
+	mem_read_handler PortAread;
+	mem_read_handler PortBread;
+	mem_write_handler PortAwrite;
+	mem_write_handler PortBwrite;
+	int register_latch;
+	unsigned char Regs[16];
+	int lastEnable;
+	unsigned int UpdateStep;
+	int PeriodA,PeriodB,PeriodC,PeriodN,PeriodE;
+	int CountA,CountB,CountC,CountN,CountE;
+	unsigned int VolA,VolB,VolC,VolE;
+	unsigned char EnvelopeA,EnvelopeB,EnvelopeC;
+	unsigned char OutputA,OutputB,OutputC,OutputN;
+	signed char CountEnv;
+	unsigned char Hold,Alternate,Attack,Holding;
+	int RNG;
+	unsigned int VolTable[32];
+};
+
+/* register id's */
+#define AY_AFINE	(0)
+#define AY_ACOARSE	(1)
+#define AY_BFINE	(2)
+#define AY_BCOARSE	(3)
+#define AY_CFINE	(4)
+#define AY_CCOARSE	(5)
+#define AY_NOISEPER	(6)
+#define AY_ENABLE	(7)
+#define AY_AVOL		(8)
+#define AY_BVOL		(9)
+#define AY_CVOL		(10)
+#define AY_EFINE	(11)
+#define AY_ECOARSE	(12)
+#define AY_ESHAPE	(13)
+
+#define AY_PORTA	(14)
+#define AY_PORTB	(15)
+
+
+static struct AY8910 AYPSG[MAX_8910];		/* array of PSG's */
+
+
+
+static void _AYWriteReg(int n, int r, int v)
+{
+	struct AY8910 *PSG = &AYPSG[n];
+	int old;
+
+
+	PSG->Regs[r] = v;
+
+	/* A note about the period of tones, noise and envelope: for speed reasons,*/
+	/* we count down from the period to 0, but careful studies of the chip     */
+	/* output prove that it instead counts up from 0 until the counter becomes */
+	/* greater or equal to the period. This is an important difference when the*/
+	/* program is rapidly changing the period to modulate the sound.           */
+	/* To compensate for the difference, when the period is changed we adjust  */
+	/* our internal counter.                                                   */
+	/* Also, note that period = 0 is the same as period = 1. This is mentioned */
+	/* in the YM2203 data sheets. However, this does NOT apply to the Envelope */
+	/* period. In that case, period = 0 is half as period = 1. */
+	switch( r )
+	{
+	case AY_AFINE:
+	case AY_ACOARSE:
+		PSG->Regs[AY_ACOARSE] &= 0x0f;
+		old = PSG->PeriodA;
+		PSG->PeriodA = (PSG->Regs[AY_AFINE] + 256 * PSG->Regs[AY_ACOARSE]) * PSG->UpdateStep;
+		if (PSG->PeriodA == 0) PSG->PeriodA = PSG->UpdateStep;
+		PSG->CountA += PSG->PeriodA - old;
+		if (PSG->CountA <= 0) PSG->CountA = 1;
+		break;
+	case AY_BFINE:
+	case AY_BCOARSE:
+		PSG->Regs[AY_BCOARSE] &= 0x0f;
+		old = PSG->PeriodB;
+		PSG->PeriodB = (PSG->Regs[AY_BFINE] + 256 * PSG->Regs[AY_BCOARSE]) * PSG->UpdateStep;
+		if (PSG->PeriodB == 0) PSG->PeriodB = PSG->UpdateStep;
+		PSG->CountB += PSG->PeriodB - old;
+		if (PSG->CountB <= 0) PSG->CountB = 1;
+		break;
+	case AY_CFINE:
+	case AY_CCOARSE:
+		PSG->Regs[AY_CCOARSE] &= 0x0f;
+		old = PSG->PeriodC;
+		PSG->PeriodC = (PSG->Regs[AY_CFINE] + 256 * PSG->Regs[AY_CCOARSE]) * PSG->UpdateStep;
+		if (PSG->PeriodC == 0) PSG->PeriodC = PSG->UpdateStep;
+		PSG->CountC += PSG->PeriodC - old;
+		if (PSG->CountC <= 0) PSG->CountC = 1;
+		break;
+	case AY_NOISEPER:
+		PSG->Regs[AY_NOISEPER] &= 0x1f;
+		old = PSG->PeriodN;
+		PSG->PeriodN = PSG->Regs[AY_NOISEPER] * PSG->UpdateStep;
+		if (PSG->PeriodN == 0) PSG->PeriodN = PSG->UpdateStep;
+		PSG->CountN += PSG->PeriodN - old;
+		if (PSG->CountN <= 0) PSG->CountN = 1;
+		break;
+	case AY_ENABLE:
+		if ((PSG->lastEnable == -1) ||
+		    ((PSG->lastEnable & 0x40) != (PSG->Regs[AY_ENABLE] & 0x40)))
+		{
+			/* write out 0xff if port set to input */
+			if (PSG->PortAwrite)
+				(*PSG->PortAwrite)(0, (PSG->Regs[AY_ENABLE] & 0x40) ? PSG->Regs[AY_PORTA] : 0xff);
+		}
+
+		if ((PSG->lastEnable == -1) ||
+		    ((PSG->lastEnable & 0x80) != (PSG->Regs[AY_ENABLE] & 0x80)))
+		{
+			/* write out 0xff if port set to input */
+			if (PSG->PortBwrite)
+				(*PSG->PortBwrite)(0, (PSG->Regs[AY_ENABLE] & 0x80) ? PSG->Regs[AY_PORTB] : 0xff);
+		}
+
+		PSG->lastEnable = PSG->Regs[AY_ENABLE];
+		break;
+	case AY_AVOL:
+		PSG->Regs[AY_AVOL] &= 0x1f;
+		PSG->EnvelopeA = PSG->Regs[AY_AVOL] & 0x10;
+		PSG->VolA = PSG->EnvelopeA ? PSG->VolE : PSG->VolTable[PSG->Regs[AY_AVOL] ? PSG->Regs[AY_AVOL]*2+1 : 0];
+		break;
+	case AY_BVOL:
+		PSG->Regs[AY_BVOL] &= 0x1f;
+		PSG->EnvelopeB = PSG->Regs[AY_BVOL] & 0x10;
+		PSG->VolB = PSG->EnvelopeB ? PSG->VolE : PSG->VolTable[PSG->Regs[AY_BVOL] ? PSG->Regs[AY_BVOL]*2+1 : 0];
+		break;
+	case AY_CVOL:
+		PSG->Regs[AY_CVOL] &= 0x1f;
+		PSG->EnvelopeC = PSG->Regs[AY_CVOL] & 0x10;
+		PSG->VolC = PSG->EnvelopeC ? PSG->VolE : PSG->VolTable[PSG->Regs[AY_CVOL] ? PSG->Regs[AY_CVOL]*2+1 : 0];
+		break;
+	case AY_EFINE:
+	case AY_ECOARSE:
+		old = PSG->PeriodE;
+		PSG->PeriodE = ((PSG->Regs[AY_EFINE] + 256 * PSG->Regs[AY_ECOARSE])) * PSG->UpdateStep;
+		if (PSG->PeriodE == 0) PSG->PeriodE = PSG->UpdateStep / 2;
+		PSG->CountE += PSG->PeriodE - old;
+		if (PSG->CountE <= 0) PSG->CountE = 1;
+		break;
+	case AY_ESHAPE:
+		/* envelope shapes:
+		C AtAlH
+		0 0 x x  \___
+
+		0 1 x x  /___
+
+		1 0 0 0  \\\\
+
+		1 0 0 1  \___
+
+		1 0 1 0  \/\/
+		          ___
+		1 0 1 1  \
+
+		1 1 0 0  ////
+		          ___
+		1 1 0 1  /
+
+		1 1 1 0  /\/\
+
+		1 1 1 1  /___
+
+		The envelope counter on the AY-3-8910 has 16 steps. On the YM2149 it
+		has twice the steps, happening twice as fast. Since the end result is
+		just a smoother curve, we always use the YM2149 behaviour.
+		*/
+		PSG->Regs[AY_ESHAPE] &= 0x0f;
+		PSG->Attack = (PSG->Regs[AY_ESHAPE] & 0x04) ? 0x1f : 0x00;
+		if ((PSG->Regs[AY_ESHAPE] & 0x08) == 0)
+		{
+			/* if Continue = 0, map the shape to the equivalent one which has Continue = 1 */
+			PSG->Hold = 1;
+			PSG->Alternate = PSG->Attack;
+		}
+		else
+		{
+			PSG->Hold = PSG->Regs[AY_ESHAPE] & 0x01;
+			PSG->Alternate = PSG->Regs[AY_ESHAPE] & 0x02;
+		}
+		PSG->CountE = PSG->PeriodE;
+		PSG->CountEnv = 0x1f;
+		PSG->Holding = 0;
+		PSG->VolE = PSG->VolTable[PSG->CountEnv ^ PSG->Attack];
+		if (PSG->EnvelopeA) PSG->VolA = PSG->VolE;
+		if (PSG->EnvelopeB) PSG->VolB = PSG->VolE;
+		if (PSG->EnvelopeC) PSG->VolC = PSG->VolE;
+		break;
+	case AY_PORTA:
+		if (PSG->Regs[AY_ENABLE] & 0x40)
+		{
+			if (PSG->PortAwrite)
+				(*PSG->PortAwrite)(0, PSG->Regs[AY_PORTA]);
+			else
+				logerror("PC %04x: warning - write %02x to 8910 #%d Port A\n",activecpu_get_pc(),PSG->Regs[AY_PORTA],n);
+		}
+		else
+		{
+			logerror("warning: write to 8910 #%d Port A set as input - ignored\n",n);
+		}
+		break;
+	case AY_PORTB:
+		if (PSG->Regs[AY_ENABLE] & 0x80)
+		{
+			if (PSG->PortBwrite)
+				(*PSG->PortBwrite)(0, PSG->Regs[AY_PORTB]);
+			else
+				logerror("PC %04x: warning - write %02x to 8910 #%d Port B\n",activecpu_get_pc(),PSG->Regs[AY_PORTB],n);
+		}
+		else
+		{
+			logerror("warning: write to 8910 #%d Port B set as input - ignored\n",n);
+		}
+		break;
+	}
+}
+
+
+/* write a register on AY8910 chip number 'n' */
+static void AYWriteReg(int chip, int r, int v)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+
+
+	if (r > 15) return;
+	if (r < 14)
+	{
+		if (r == AY_ESHAPE || PSG->Regs[r] != v)
+		{
+			/* update the output buffer before changing the register */
+			YM2608UpdateRequest(chip);
+		}
+	}
+
+	_AYWriteReg(chip,r,v);
+}
+
+
+
+static unsigned char AYReadReg(int n, int r)
+{
+	struct AY8910 *PSG = &AYPSG[n];
+
+
+	if (r > 15) return 0;
+
+	switch (r)
+	{
+	case AY_PORTA:
+		if ((PSG->Regs[AY_ENABLE] & 0x40) != 0)
+			logerror("warning: read from 8910 #%d Port A set as output\n",n);
+		else if (PSG->PortAread) PSG->Regs[AY_PORTA] = (*PSG->PortAread)(0);
+		else logerror("PC %04x: warning - read 8910 #%d Port A\n",activecpu_get_pc(),n);
+		break;
+	case AY_PORTB:
+		if ((PSG->Regs[AY_ENABLE] & 0x80) != 0)
+			logerror("warning: read from 8910 #%d Port B set as output\n",n);
+		else if (PSG->PortBread) PSG->Regs[AY_PORTB] = (*PSG->PortBread)(0);
+		else logerror("PC %04x: warning - read 8910 #%d Port B\n",activecpu_get_pc(),n);
+		break;
+	}
+	return PSG->Regs[r];
+}
+
+
+void AY8910Write(int chip,int a,int data)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+
+	if (a & 1)
+	{	/* Data port */
+		AYWriteReg(chip,PSG->register_latch,data);
+	}
+	else
+	{	/* Register port */
+		PSG->register_latch = data & 0x0f;
+	}
+}
+
+int AY8910Read(int chip)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+
+	return AYReadReg(chip,PSG->register_latch);
+}
+
+
+/* AY8910 interface */
+
+void AY8910Update(int chip,INT16 **buffer,int length)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+	INT16 *buf1,*buf2,*buf3;
+	int outn;
+
+	buf1 = buffer[0];
+	buf2 = buffer[1];
+	buf3 = buffer[2];
+
+
+	/* The 8910 has three outputs, each output is the mix of one of the three */
+	/* tone generators and of the (single) noise generator. The two are mixed */
+	/* BEFORE going into the DAC. The formula to mix each channel is: */
+	/* (ToneOn | ToneDisable) & (NoiseOn | NoiseDisable). */
+	/* Note that this means that if both tone and noise are disabled, the output */
+	/* is 1, not 0, and can be modulated changing the volume. */
+
+
+	/* If the channels are disabled, set their output to 1, and increase the */
+	/* counter, if necessary, so they will not be inverted during this update. */
+	/* Setting the output to 1 is necessary because a disabled channel is locked */
+	/* into the ON state (see above); and it has no effect if the volume is 0. */
+	/* If the volume is 0, increase the counter, but don't touch the output. */
+	if (PSG->Regs[AY_ENABLE] & 0x01)
+	{
+		if (PSG->CountA <= length*STEP) PSG->CountA += length*STEP;
+		PSG->OutputA = 1;
+	}
+	else if (PSG->Regs[AY_AVOL] == 0)
+	{
+		/* note that I do count += length, NOT count = length + 1. You might think */
+		/* it's the same since the volume is 0, but doing the latter could cause */
+		/* interferencies when the program is rapidly modulating the volume. */
+		if (PSG->CountA <= length*STEP) PSG->CountA += length*STEP;
+	}
+	if (PSG->Regs[AY_ENABLE] & 0x02)
+	{
+		if (PSG->CountB <= length*STEP) PSG->CountB += length*STEP;
+		PSG->OutputB = 1;
+	}
+	else if (PSG->Regs[AY_BVOL] == 0)
+	{
+		if (PSG->CountB <= length*STEP) PSG->CountB += length*STEP;
+	}
+	if (PSG->Regs[AY_ENABLE] & 0x04)
+	{
+		if (PSG->CountC <= length*STEP) PSG->CountC += length*STEP;
+		PSG->OutputC = 1;
+	}
+	else if (PSG->Regs[AY_CVOL] == 0)
+	{
+		if (PSG->CountC <= length*STEP) PSG->CountC += length*STEP;
+	}
+
+	/* for the noise channel we must not touch OutputN - it's also not necessary */
+	/* since we use outn. */
+	if ((PSG->Regs[AY_ENABLE] & 0x38) == 0x38)	/* all off */
+		if (PSG->CountN <= length*STEP) PSG->CountN += length*STEP;
+
+	outn = (PSG->OutputN | PSG->Regs[AY_ENABLE]);
+
+
+	/* buffering loop */
+	while (length)
+	{
+		int vola,volb,volc;
+		int left;
+
+
+		/* vola, volb and volc keep track of how long each square wave stays */
+		/* in the 1 position during the sample period. */
+		vola = volb = volc = 0;
+
+		left = STEP;
+		do
+		{
+			int nextevent;
+
+
+			if (PSG->CountN < left) nextevent = PSG->CountN;
+			else nextevent = left;
+
+			if (outn & 0x08)
+			{
+				if (PSG->OutputA) vola += PSG->CountA;
+				PSG->CountA -= nextevent;
+				/* PeriodA is the half period of the square wave. Here, in each */
+				/* loop I add PeriodA twice, so that at the end of the loop the */
+				/* square wave is in the same status (0 or 1) it was at the start. */
+				/* vola is also incremented by PeriodA, since the wave has been 1 */
+				/* exactly half of the time, regardless of the initial position. */
+				/* If we exit the loop in the middle, OutputA has to be inverted */
+				/* and vola incremented only if the exit status of the square */
+				/* wave is 1. */
+				while (PSG->CountA <= 0)
+				{
+					PSG->CountA += PSG->PeriodA;
+					if (PSG->CountA > 0)
+					{
+						PSG->OutputA ^= 1;
+						if (PSG->OutputA) vola += PSG->PeriodA;
+						break;
+					}
+					PSG->CountA += PSG->PeriodA;
+					vola += PSG->PeriodA;
+				}
+				if (PSG->OutputA) vola -= PSG->CountA;
+			}
+			else
+			{
+				PSG->CountA -= nextevent;
+				while (PSG->CountA <= 0)
+				{
+					PSG->CountA += PSG->PeriodA;
+					if (PSG->CountA > 0)
+					{
+						PSG->OutputA ^= 1;
+						break;
+					}
+					PSG->CountA += PSG->PeriodA;
+				}
+			}
+
+			if (outn & 0x10)
+			{
+				if (PSG->OutputB) volb += PSG->CountB;
+				PSG->CountB -= nextevent;
+				while (PSG->CountB <= 0)
+				{
+					PSG->CountB += PSG->PeriodB;
+					if (PSG->CountB > 0)
+					{
+						PSG->OutputB ^= 1;
+						if (PSG->OutputB) volb += PSG->PeriodB;
+						break;
+					}
+					PSG->CountB += PSG->PeriodB;
+					volb += PSG->PeriodB;
+				}
+				if (PSG->OutputB) volb -= PSG->CountB;
+			}
+			else
+			{
+				PSG->CountB -= nextevent;
+				while (PSG->CountB <= 0)
+				{
+					PSG->CountB += PSG->PeriodB;
+					if (PSG->CountB > 0)
+					{
+						PSG->OutputB ^= 1;
+						break;
+					}
+					PSG->CountB += PSG->PeriodB;
+				}
+			}
+
+			if (outn & 0x20)
+			{
+				if (PSG->OutputC) volc += PSG->CountC;
+				PSG->CountC -= nextevent;
+				while (PSG->CountC <= 0)
+				{
+					PSG->CountC += PSG->PeriodC;
+					if (PSG->CountC > 0)
+					{
+						PSG->OutputC ^= 1;
+						if (PSG->OutputC) volc += PSG->PeriodC;
+						break;
+					}
+					PSG->CountC += PSG->PeriodC;
+					volc += PSG->PeriodC;
+				}
+				if (PSG->OutputC) volc -= PSG->CountC;
+			}
+			else
+			{
+				PSG->CountC -= nextevent;
+				while (PSG->CountC <= 0)
+				{
+					PSG->CountC += PSG->PeriodC;
+					if (PSG->CountC > 0)
+					{
+						PSG->OutputC ^= 1;
+						break;
+					}
+					PSG->CountC += PSG->PeriodC;
+				}
+			}
+
+			PSG->CountN -= nextevent;
+			if (PSG->CountN <= 0)
+			{
+				/* Is noise output going to change? */
+				if ((PSG->RNG + 1) & 2)	/* (bit0^bit1)? */
+				{
+					PSG->OutputN = ~PSG->OutputN;
+					outn = (PSG->OutputN | PSG->Regs[AY_ENABLE]);
+				}
+
+				/* The Random Number Generator of the 8910 is a 17-bit shift */
+				/* register. The input to the shift register is bit0 XOR bit2 */
+				/* (bit0 is the output). */
+
+				/* The following is a fast way to compute bit 17 = bit0^bit2. */
+				/* Instead of doing all the logic operations, we only check */
+				/* bit 0, relying on the fact that after two shifts of the */
+				/* register, what now is bit 2 will become bit 0, and will */
+				/* invert, if necessary, bit 16, which previously was bit 18. */
+				if (PSG->RNG & 1) PSG->RNG ^= 0x28000;
+				PSG->RNG >>= 1;
+				PSG->CountN += PSG->PeriodN;
+			}
+
+			left -= nextevent;
+		} while (left > 0);
+
+		/* update envelope */
+		if (PSG->Holding == 0)
+		{
+			PSG->CountE -= STEP;
+			if (PSG->CountE <= 0)
+			{
+				do
+				{
+					PSG->CountEnv--;
+					PSG->CountE += PSG->PeriodE;
+				} while (PSG->CountE <= 0);
+
+				/* check envelope current position */
+				if (PSG->CountEnv < 0)
+				{
+					if (PSG->Hold)
+					{
+						if (PSG->Alternate)
+							PSG->Attack ^= 0x1f;
+						PSG->Holding = 1;
+						PSG->CountEnv = 0;
+					}
+					else
+					{
+						/* if CountEnv has looped an odd number of times (usually 1), */
+						/* invert the output. */
+						if (PSG->Alternate && (PSG->CountEnv & 0x20))
+ 							PSG->Attack ^= 0x1f;
+
+						PSG->CountEnv &= 0x1f;
+					}
+				}
+
+				PSG->VolE = PSG->VolTable[PSG->CountEnv ^ PSG->Attack];
+				/* reload volume */
+				if (PSG->EnvelopeA) PSG->VolA = PSG->VolE;
+				if (PSG->EnvelopeB) PSG->VolB = PSG->VolE;
+				if (PSG->EnvelopeC) PSG->VolC = PSG->VolE;
+			}
+		}
+
+		*(buf1++) = (vola * PSG->VolA) / STEP;
+		*(buf2++) = (volb * PSG->VolB) / STEP;
+		*(buf3++) = (volc * PSG->VolC) / STEP;
+
+		length--;
+	}
+}
+
+
+void AY8910_set_clock(int chip,int clock)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+
+	/* the step clock for the tone and noise generators is the chip clock    */
+	/* divided by 8; for the envelope generator of the AY-3-8910, it is half */
+	/* that much (clock/16), but the envelope of the YM2149 goes twice as    */
+	/* fast, therefore again clock/8.                                        */
+	/* Here we calculate the number of steps which happen during one sample  */
+	/* at the given sample rate. No. of events = sample rate / (clock/8).    */
+	/* STEP is a multiplier used to turn the fraction into a fixed point     */
+	/* number.                                                               */
+	PSG->UpdateStep = ((double)STEP * PSG->SampleRate * 8) / clock;
+}
+
+
+static void build_mixer_table(int chip)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+	int i;
+	double out;
+
+
+	/* calculate the volume->voltage conversion table */
+	/* The AY-3-8910 has 16 levels, in a logarithmic scale (3dB per step) */
+	/* The YM2149 still has 16 levels for the tone generators, but 32 for */
+	/* the envelope generator (1.5dB per step). */
+	out = MAX_OUTPUT;
+	for (i = 31;i > 0;i--)
+	{
+		PSG->VolTable[i] = out + 0.5;	/* round to nearest */
+
+		out /= 1.188502227;	/* = 10 ^ (1.5/20) = 1.5dB */
+	}
+	PSG->VolTable[0] = 0;
+}
+
+
+
+void AY8910_reset(int chip)
+{
+	int i;
+	struct AY8910 *PSG = &AYPSG[chip];
+
+	PSG->register_latch = 0;
+	PSG->RNG = 1;
+	PSG->OutputA = 0;
+	PSG->OutputB = 0;
+	PSG->OutputC = 0;
+	PSG->OutputN = 0xff;
+	PSG->lastEnable = -1;	/* force a write */
+	for (i = 0;i < AY_PORTA;i++)
+		_AYWriteReg(chip,i,0);	/* AYWriteReg() uses the timer system; we cannot */
+								/* call it at this time because the timer system */
+								/* has not been initialized. */
+}
+
+void AY8910_sh_reset(void)
+{
+	int i;
+
+	for (i = 0;i < num + ym_num;i++)
+		AY8910_reset(i);
+}
+
+static int AY8910_init(int chip,
+		int clock,int sample_rate,
+		mem_read_handler portAread,mem_read_handler portBread,
+		mem_write_handler portAwrite,mem_write_handler portBwrite)
+{
+	struct AY8910 *PSG = &AYPSG[chip];
+
+	memset(PSG,0,sizeof(struct AY8910));
+	PSG->SampleRate = sample_rate;
+	PSG->PortAread = portAread;
+	PSG->PortBread = portBread;
+	PSG->PortAwrite = portAwrite;
+	PSG->PortBwrite = portBwrite;
+
+	AY8910_set_clock(chip,clock);
+
+	return 0;
+}
+
+
+int AY8910_sh_start(const struct MachineSound *msound, int sample_rate)
+{
+	int chip;
+	const struct AY8910interface *intf = msound->sound_interface;
+
+	num = intf->num;
+
+	for (chip = 0;chip < num;chip++)
+	{
+		if (AY8910_init(chip+ym_num,intf->baseclock,
+				sample_rate,
+				intf->portAread[chip],intf->portBread[chip],
+				intf->portAwrite[chip],intf->portBwrite[chip]) != 0)
+			return 1;
+		build_mixer_table(chip+ym_num);
+	}
+	return 0;
+}
+
+void AY8910_sh_stop(void)
+{
+	num = 0;
+}
+
+int AY8910_sh_start_ym(const struct MachineSound *msound, int sample_rate)
+{
+	int chip;
+	const struct AY8910interface *intf = msound->sound_interface;
+
+	ym_num = intf->num;
+	ay8910_index_ym = num;
+
+	for (chip = 0;chip < ym_num;chip++)
+	{
+		if (AY8910_init(chip+num,intf->baseclock,
+				sample_rate,
+				intf->portAread[chip],intf->portBread[chip],
+				intf->portAwrite[chip],intf->portBwrite[chip]) != 0)
+			return 1;
+		build_mixer_table(chip+num);
+	}
+	return 0;
+}
+
+void AY8910_sh_stop_ym(void)
+{
+	ym_num = 0;
+}
+
diff --git a/qemu/hw/ay8910.h b/qemu/hw/ay8910.h
new file mode 100644
index 0000000..4e96b34
--- /dev/null
+++ b/qemu/hw/ay8910.h
@@ -0,0 +1,41 @@
+#ifndef AY8910_H
+#define AY8910_H
+
+#include "fm_def.h"
+
+#define MAX_8910 5
+#define ALL_8910_CHANNELS -1
+
+struct AY8910interface
+{
+	int num;	/* total number of 8910 in the machine */
+	int baseclock;
+	mem_read_handler portAread[MAX_8910];
+	mem_read_handler portBread[MAX_8910];
+	mem_write_handler portAwrite[MAX_8910];
+	mem_write_handler portBwrite[MAX_8910];
+	void (*handler[MAX_8910])(int irq);	/* IRQ handler for the YM2203 */
+};
+
+void AY8910_reset(int chip);
+
+void AY8910Update(int chip,INT16 **buffer,int length);
+void AY8910_set_clock(int chip,int _clock);
+
+void AY8910Write(int chip,int a,int data);
+int AY8910Read(int chip);
+
+int AY8910_sh_start(const struct MachineSound *msound, int sample_rate);
+void AY8910_sh_stop(void);
+void AY8910_sh_reset(void);
+
+/*********** An interface for SSG of YM2203 ***********/
+
+/* When both of AY8910 and YM2203 or YM2608 or YM2610 are used.      */
+/* It must be called AY8910_sh_start () before AY8910_sh_start_ym()  */
+
+extern int ay8910_index_ym;
+
+void AY8910_sh_stop_ym(void);
+int AY8910_sh_start_ym(const struct MachineSound *msound, int sample_rate);
+#endif

^ permalink raw reply related	[flat|nested] 16+ messages in thread

end of thread, other threads:[~2009-10-29 13:34 UTC | newest]

Thread overview: 16+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2009-10-28 16:50 [Qemu-devel] [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59 TAKEDA, toshiya
2009-10-28 20:08 ` Stuart Brady
2009-10-28 21:55   ` [Qemu-devel] " Paolo Bonzini
2009-10-29  0:35     ` Roy Tam
2009-10-29  3:05       ` Natalia Portillo
2009-10-29  3:55         ` Roy Tam
2009-10-29  8:52           ` Paolo Bonzini
2009-10-29  7:52     ` Stuart Brady
2009-10-29  8:03       ` Roy Tam
2009-10-29  8:14         ` malc
2009-10-29  9:30           ` Laurent Desnogues
2009-10-29  9:44             ` malc
2009-10-29  9:45               ` Laurent Desnogues
2009-10-29 10:05                 ` malc
2009-10-29 13:33             ` TAKEDA, toshiya
2009-10-29  9:55           ` Roy Tam

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