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[Qemu-devel] [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59
|
From: |
TAKEDA, toshiya |
|
Subject: |
[Qemu-devel] [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59 |
|
Date: |
Thu, 29 Oct 2009 01:50:11 +0900 |
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
- [Qemu-devel] [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59,
TAKEDA, toshiya <=
- [Qemu-devel] Re: [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59, Stuart Brady, 2009/10/29
- Re: [Qemu-devel] Re: [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59, Roy Tam, 2009/10/29
- Re: [Qemu-devel] Re: [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59, malc, 2009/10/29
- Re: [Qemu-devel] Re: [PATCH v3 22/25] ay8910: YM2608 core forked from MAME 0.59, Laurent Desnogues, 2009/10/29