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author Wilbert Pol <wilbert@jdg.info>2012-10-16 21:18:06 +0000
committer Wilbert Pol <wilbert@jdg.info>2012-10-16 21:18:06 +0000
commit065c06201b36f9fdd0ee7b5b1862cc8a5507b02c (patch)
treeeb8611ed78dcd7a261cce3f032fbc77ceff20b2e /src/emu/sound/t6w28.c
parent3fcea59977c82a7be8eec192c49e5dc524eb285d (diff)
t6w28.c: Converted to C++. [Wilbert Pol]
Diffstat (limited to 'src/emu/sound/t6w28.c')
-rw-r--r--src/emu/sound/t6w28.c291
1 files changed, 113 insertions, 178 deletions
diff --git a/src/emu/sound/t6w28.c b/src/emu/sound/t6w28.c
index ad83a948593..e42899dbae1 100644
--- a/src/emu/sound/t6w28.c
+++ b/src/emu/sound/t6w28.c
@@ -37,53 +37,25 @@ Offset 0:
#define STEP 0x10000
-struct t6w28_state
+WRITE8_MEMBER( t6w28_device::write )
{
- sound_stream * Channel;
- int SampleRate;
- int VolTable[16]; /* volume table */
- INT32 Register[16]; /* registers */
- INT32 LastRegister[2]; /* last register written */
- INT32 Volume[8]; /* volume of voice 0-2 and noise */
- UINT32 RNG[2]; /* noise generator */
- INT32 NoiseMode[2]; /* active noise mode */
- INT32 FeedbackMask; /* mask for feedback */
- INT32 WhitenoiseTaps; /* mask for white noise taps */
- INT32 WhitenoiseInvert; /* white noise invert flag */
- INT32 Period[8];
- INT32 Count[8];
- INT32 Output[8];
-};
-
-
-INLINE t6w28_state *get_safe_token(device_t *device)
-{
- assert(device != NULL);
- assert(device->type() == T6W28);
- return (t6w28_state *)downcast<t6w28_device *>(device)->token();
-}
-
-
-WRITE8_DEVICE_HANDLER( t6w28_w )
-{
- t6w28_state *R = get_safe_token(device);
int n, r, c;
/* update the output buffer before changing the registers */
- R->Channel->update();
+ m_channel->update();
offset &= 1;
if (data & 0x80)
{
r = (data & 0x70) >> 4;
- R->LastRegister[offset] = r;
- R->Register[offset * 8 + r] = (R->Register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
+ m_last_register[offset] = r;
+ m_register[offset * 8 + r] = (m_register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
}
else
{
- r = R->LastRegister[offset];
+ r = m_last_register[offset];
}
c = r/2;
switch (r)
@@ -91,34 +63,34 @@ WRITE8_DEVICE_HANDLER( t6w28_w )
case 0: /* tone 0 : frequency */
case 2: /* tone 1 : frequency */
case 4: /* tone 2 : frequency */
- if ((data & 0x80) == 0) R->Register[offset * 8 + r] = (R->Register[offset * 8 + r] & 0x0f) | ((data & 0x3f) << 4);
- R->Period[offset * 4 + c] = STEP * R->Register[offset * 8 + r];
- if (R->Period[offset * 4 + c] == 0) R->Period[offset * 4 + c] = STEP;
+ if ((data & 0x80) == 0) m_register[offset * 8 + r] = (m_register[offset * 8 + r] & 0x0f) | ((data & 0x3f) << 4);
+ m_period[offset * 4 + c] = STEP * m_register[offset * 8 + r];
+ if (m_period[offset * 4 + c] == 0) m_period[offset * 4 + c] = STEP;
if (r == 4)
{
/* update noise shift frequency */
- if ((R->Register[offset * 8 + 6] & 0x03) == 0x03)
- R->Period[offset * 4 + 3] = 2 * R->Period[offset * 4 + 2];
+ if ((m_register[offset * 8 + 6] & 0x03) == 0x03)
+ m_period[offset * 4 + 3] = 2 * m_period[offset * 4 + 2];
}
break;
case 1: /* tone 0 : volume */
case 3: /* tone 1 : volume */
case 5: /* tone 2 : volume */
case 7: /* noise : volume */
- R->Volume[offset * 4 + c] = R->VolTable[data & 0x0f];
- if ((data & 0x80) == 0) R->Register[offset * 8 + r] = (R->Register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
+ m_volume[offset * 4 + c] = m_vol_table[data & 0x0f];
+ if ((data & 0x80) == 0) m_register[offset * 8 + r] = (m_register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
break;
case 6: /* noise : frequency, mode */
{
- if ((data & 0x80) == 0) R->Register[offset * 8 + r] = (R->Register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
- n = R->Register[offset * 8 + 6];
- R->NoiseMode[offset] = (n & 4) ? 1 : 0;
+ if ((data & 0x80) == 0) m_register[offset * 8 + r] = (m_register[offset * 8 + r] & 0x3f0) | (data & 0x0f);
+ n = m_register[offset * 8 + 6];
+ m_noise_mode[offset] = (n & 4) ? 1 : 0;
/* N/512,N/1024,N/2048,Tone #3 output */
- R->Period[offset * 4 + 3] = ((n&3) == 3) ? 2 * R->Period[offset * 4 + 2] : (STEP << (5+(n&3)));
+ m_period[offset * 4 + 3] = ((n&3) == 3) ? 2 * m_period[offset * 4 + 2] : (STEP << (5+(n&3)));
/* Reset noise shifter */
- R->RNG[offset] = R->FeedbackMask; /* this is correct according to the smspower document */
- //R->RNG = 0xF35; /* this is not, but sounds better in do run run */
- R->Output[offset * 4 + 3] = R->RNG[offset] & 1;
+ m_rng[offset] = m_feedback_mask; /* this is correct according to the smspower document */
+ //m_rng = 0xF35; /* this is not, but sounds better in do run run */
+ m_output[offset * 4 + 3] = m_rng[offset] & 1;
}
break;
}
@@ -126,10 +98,13 @@ WRITE8_DEVICE_HANDLER( t6w28_w )
-static STREAM_UPDATE( t6w28_update )
+//-------------------------------------------------
+// sound_stream_update - handle a stream update
+//-------------------------------------------------
+
+void t6w28_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples)
{
int i;
- t6w28_state *R = (t6w28_state *)param;
stream_sample_t *buffer0 = outputs[0];
stream_sample_t *buffer1 = outputs[1];
@@ -137,12 +112,12 @@ static STREAM_UPDATE( t6w28_update )
/* If the volume is 0, increase the counter */
for (i = 0;i < 8;i++)
{
- if (R->Volume[i] == 0)
+ if (m_volume[i] == 0)
{
/* note that I do count += samples, NOT count = samples + 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 (R->Count[i] <= samples*STEP) R->Count[i] += samples*STEP;
+ if (m_count[i] <= samples*STEP) m_count[i] += samples*STEP;
}
}
@@ -159,56 +134,56 @@ static STREAM_UPDATE( t6w28_update )
for (i = 2;i < 3;i++)
{
- if (R->Output[i]) vol[i] += R->Count[i];
- R->Count[i] -= STEP;
- /* Period[i] is the half period of the square wave. Here, in each */
- /* loop I add Period[i] twice, so that at the end of the loop the */
+ if (m_output[i]) vol[i] += m_count[i];
+ m_count[i] -= STEP;
+ /* m_period[i] is the half period of the square wave. Here, in each */
+ /* loop I add m_period[i] 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. */
- /* vol[i] is also incremented by Period[i], since the wave has been 1 */
+ /* vol[i] is also incremented by m_period[i], since the wave has been 1 */
/* exactly half of the time, regardless of the initial position. */
- /* If we exit the loop in the middle, Output[i] has to be inverted */
+ /* If we exit the loop in the middle, m_output[i] has to be inverted */
/* and vol[i] incremented only if the exit status of the square */
/* wave is 1. */
- while (R->Count[i] <= 0)
+ while (m_count[i] <= 0)
{
- R->Count[i] += R->Period[i];
- if (R->Count[i] > 0)
+ m_count[i] += m_period[i];
+ if (m_count[i] > 0)
{
- R->Output[i] ^= 1;
- if (R->Output[i]) vol[i] += R->Period[i];
+ m_output[i] ^= 1;
+ if (m_output[i]) vol[i] += m_period[i];
break;
}
- R->Count[i] += R->Period[i];
- vol[i] += R->Period[i];
+ m_count[i] += m_period[i];
+ vol[i] += m_period[i];
}
- if (R->Output[i]) vol[i] -= R->Count[i];
+ if (m_output[i]) vol[i] -= m_count[i];
}
for (i = 4;i < 7;i++)
{
- if (R->Output[i]) vol[i] += R->Count[i];
- R->Count[i] -= STEP;
- /* Period[i] is the half period of the square wave. Here, in each */
- /* loop I add Period[i] twice, so that at the end of the loop the */
+ if (m_output[i]) vol[i] += m_count[i];
+ m_count[i] -= STEP;
+ /* m_period[i] is the half period of the square wave. Here, in each */
+ /* loop I add m_period[i] 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. */
- /* vol[i] is also incremented by Period[i], since the wave has been 1 */
+ /* vol[i] is also incremented by m_period[i], since the wave has been 1 */
/* exactly half of the time, regardless of the initial position. */
- /* If we exit the loop in the middle, Output[i] has to be inverted */
+ /* If we exit the loop in the middle, m_output[i] has to be inverted */
/* and vol[i] incremented only if the exit status of the square */
/* wave is 1. */
- while (R->Count[i] <= 0)
+ while (m_count[i] <= 0)
{
- R->Count[i] += R->Period[i];
- if (R->Count[i] > 0)
+ m_count[i] += m_period[i];
+ if (m_count[i] > 0)
{
- R->Output[i] ^= 1;
- if (R->Output[i]) vol[i] += R->Period[i];
+ m_output[i] ^= 1;
+ if (m_output[i]) vol[i] += m_period[i];
break;
}
- R->Count[i] += R->Period[i];
- vol[i] += R->Period[i];
+ m_count[i] += m_period[i];
+ vol[i] += m_period[i];
}
- if (R->Output[i]) vol[i] -= R->Count[i];
+ if (m_output[i]) vol[i] -= m_count[i];
}
left = STEP;
@@ -217,52 +192,52 @@ static STREAM_UPDATE( t6w28_update )
int nextevent;
- if (R->Count[3] < left) nextevent = R->Count[3];
+ if (m_count[3] < left) nextevent = m_count[3];
else nextevent = left;
- if (R->Output[3]) vol[3] += R->Count[3];
- R->Count[3] -= nextevent;
- if (R->Count[3] <= 0)
+ if (m_output[3]) vol[3] += m_count[3];
+ m_count[3] -= nextevent;
+ if (m_count[3] <= 0)
{
- if (R->NoiseMode[0] == 1) /* White Noise Mode */
+ if (m_noise_mode[0] == 1) /* White Noise Mode */
{
- if (((R->RNG[0] & R->WhitenoiseTaps) != R->WhitenoiseTaps) && ((R->RNG[0] & R->WhitenoiseTaps) != 0)) /* crappy xor! */
+ if (((m_rng[0] & m_whitenoise_taps) != m_whitenoise_taps) && ((m_rng[0] & m_whitenoise_taps) != 0)) /* crappy xor! */
{
- R->RNG[0] >>= 1;
- R->RNG[0] |= R->FeedbackMask;
+ m_rng[0] >>= 1;
+ m_rng[0] |= m_feedback_mask;
}
else
{
- R->RNG[0] >>= 1;
+ m_rng[0] >>= 1;
}
- R->Output[3] = R->WhitenoiseInvert ? !(R->RNG[0] & 1) : R->RNG[0] & 1;
+ m_output[3] = m_whitenoise_invert ? !(m_rng[0] & 1) : m_rng[0] & 1;
}
else /* Periodic noise mode */
{
- if (R->RNG[0] & 1)
+ if (m_rng[0] & 1)
{
- R->RNG[0] >>= 1;
- R->RNG[0] |= R->FeedbackMask;
+ m_rng[0] >>= 1;
+ m_rng[0] |= m_feedback_mask;
}
else
{
- R->RNG[0] >>= 1;
+ m_rng[0] >>= 1;
}
- R->Output[3] = R->RNG[0] & 1;
+ m_output[3] = m_rng[0] & 1;
}
- R->Count[3] += R->Period[3];
- if (R->Output[3]) vol[3] += R->Period[3];
+ m_count[3] += m_period[3];
+ if (m_output[3]) vol[3] += m_period[3];
}
- if (R->Output[3]) vol[3] -= R->Count[3];
+ if (m_output[3]) vol[3] -= m_count[3];
left -= nextevent;
} while (left > 0);
- out0 = vol[4] * R->Volume[4] + vol[5] * R->Volume[5] +
- vol[6] * R->Volume[6] + vol[3] * R->Volume[7];
+ out0 = vol[4] * m_volume[4] + vol[5] * m_volume[5] +
+ vol[6] * m_volume[6] + vol[3] * m_volume[7];
- out1 = vol[4] * R->Volume[0] + vol[5] * R->Volume[1] +
- vol[6] * R->Volume[2] + vol[3] * R->Volume[3];
+ out1 = vol[4] * m_volume[0] + vol[5] * m_volume[1] +
+ vol[6] * m_volume[2] + vol[3] * m_volume[3];
if (out0 > MAX_OUTPUT * STEP) out0 = MAX_OUTPUT * STEP;
if (out1 > MAX_OUTPUT * STEP) out1 = MAX_OUTPUT * STEP;
@@ -276,12 +251,11 @@ static STREAM_UPDATE( t6w28_update )
-static void t6w28_set_gain(t6w28_state *R,int gain)
+void t6w28_device::set_gain(int gain)
{
int i;
double out;
-
gain &= 0xff;
/* increase max output basing on gain (0.2 dB per step) */
@@ -293,75 +267,67 @@ static void t6w28_set_gain(t6w28_state *R,int gain)
for (i = 0;i < 15;i++)
{
/* limit volume to avoid clipping */
- if (out > MAX_OUTPUT / 3) R->VolTable[i] = MAX_OUTPUT / 3;
- else R->VolTable[i] = out;
+ if (out > MAX_OUTPUT / 3) m_vol_table[i] = MAX_OUTPUT / 3;
+ else m_vol_table[i] = out;
out /= 1.258925412; /* = 10 ^ (2/20) = 2dB */
}
- R->VolTable[15] = 0;
+ m_vol_table[15] = 0;
}
-static int t6w28_init(device_t *device, t6w28_state *R)
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void t6w28_device::device_start()
{
- int sample_rate = device->clock()/16;
int i;
- R->Channel = device->machine().sound().stream_alloc(*device,0,2,sample_rate,R,t6w28_update);
-
- R->SampleRate = sample_rate;
+ m_sample_rate = clock() / 16;
+ m_channel = machine().sound().stream_alloc(*this, 0, 2, m_sample_rate, this);
- for (i = 0;i < 8;i++) R->Volume[i] = 0;
+ for (i = 0;i < 8;i++) m_volume[i] = 0;
- R->LastRegister[0] = 0;
- R->LastRegister[1] = 0;
+ m_last_register[0] = 0;
+ m_last_register[1] = 0;
for (i = 0;i < 8;i+=2)
{
- R->Register[i] = 0;
- R->Register[i + 1] = 0x0f; /* volume = 0 */
+ m_register[i] = 0;
+ m_register[i + 1] = 0x0f; /* volume = 0 */
}
for (i = 0;i < 8;i++)
{
- R->Output[i] = 0;
- R->Period[i] = R->Count[i] = STEP;
+ m_output[i] = 0;
+ m_period[i] = m_count[i] = STEP;
}
/* Default is SN76489 non-A */
- R->FeedbackMask = 0x4000; /* mask for feedback */
- R->WhitenoiseTaps = 0x03; /* mask for white noise taps */
- R->WhitenoiseInvert = 1; /* white noise invert flag */
+ m_feedback_mask = 0x4000; /* mask for feedback */
+ m_whitenoise_taps = 0x03; /* mask for white noise taps */
+ m_whitenoise_invert = 1; /* white noise invert flag */
- R->RNG[0] = R->FeedbackMask;
- R->RNG[1] = R->FeedbackMask;
- R->Output[3] = R->RNG[0] & 1;
+ m_rng[0] = m_feedback_mask;
+ m_rng[1] = m_feedback_mask;
+ m_output[3] = m_rng[0] & 1;
- return 0;
-}
-
-
-static DEVICE_START( t6w28 )
-{
- t6w28_state *chip = get_safe_token(device);
-
- if (t6w28_init(device,chip) != 0)
- fatalerror("Error creating t6w28 chip\n");
- t6w28_set_gain(chip, 0);
+ set_gain(0);
/* values from sn76489a */
- chip->FeedbackMask = 0x8000;
- chip->WhitenoiseTaps = 0x06;
- chip->WhitenoiseInvert = FALSE;
-
- device->save_item(NAME(chip->Register));
- device->save_item(NAME(chip->LastRegister));
- device->save_item(NAME(chip->Volume));
- device->save_item(NAME(chip->RNG));
- device->save_item(NAME(chip->NoiseMode));
- device->save_item(NAME(chip->Period));
- device->save_item(NAME(chip->Count));
- device->save_item(NAME(chip->Output));
+ m_feedback_mask = 0x8000;
+ m_whitenoise_taps = 0x06;
+ m_whitenoise_invert = FALSE;
+
+ save_item(NAME(m_register));
+ save_item(NAME(m_last_register));
+ save_item(NAME(m_volume));
+ save_item(NAME(m_rng));
+ save_item(NAME(m_noise_mode));
+ save_item(NAME(m_period));
+ save_item(NAME(m_count));
+ save_item(NAME(m_output));
}
const device_type T6W28 = &device_creator<t6w28_device>;
@@ -370,36 +336,5 @@ t6w28_device::t6w28_device(const machine_config &mconfig, const char *tag, devic
: device_t(mconfig, T6W28, "T6W28", tag, owner, clock),
device_sound_interface(mconfig, *this)
{
- m_token = global_alloc_clear(t6w28_state);
}
-//-------------------------------------------------
-// device_config_complete - perform any
-// operations now that the configuration is
-// complete
-//-------------------------------------------------
-
-void t6w28_device::device_config_complete()
-{
-}
-
-//-------------------------------------------------
-// device_start - device-specific startup
-//-------------------------------------------------
-
-void t6w28_device::device_start()
-{
- DEVICE_START_NAME( t6w28 )(this);
-}
-
-//-------------------------------------------------
-// sound_stream_update - handle a stream update
-//-------------------------------------------------
-
-void t6w28_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples)
-{
- // should never get here
- fatalerror("sound_stream_update called; not applicable to legacy sound devices\n");
-}
-
-