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author Olivier Galibert <galibert@pobox.com>2020-08-21 22:08:57 +0200
committer Olivier Galibert <galibert@pobox.com>2020-08-23 13:35:05 +0200
commite59030aa3d35ef42e240344b77a1505b14ac64b7 (patch)
tree8d7abbe42113f07ffe7af696c06984438b53b25c
parentf4a95041816adcfba90e0a3448dadfe7d363c1a0 (diff)
sc01: Fix pitch and closure [O. Galibert]
wow, gorf: Fix sc01 hookup [O. Galibert, Frank Palazzolo, plgDavid] Note that the dynamic clock changes will sound bad until Aaron's sound stream fixes are in.
-rw-r--r--src/devices/sound/flt_rc.cpp12
-rw-r--r--src/devices/sound/flt_rc.h25
-rw-r--r--src/devices/sound/votrax.cpp17
-rw-r--r--src/mame/drivers/astrocde.cpp19
4 files changed, 58 insertions, 15 deletions
diff --git a/src/devices/sound/flt_rc.cpp b/src/devices/sound/flt_rc.cpp
index 9a81d14aaa1..88fb3c7624f 100644
--- a/src/devices/sound/flt_rc.cpp
+++ b/src/devices/sound/flt_rc.cpp
@@ -63,6 +63,7 @@ void filter_rc_device::sound_stream_update(sound_stream &stream, stream_sample_t
switch (m_type)
{
case LOWPASS:
+ case LOWPASS_2C:
while (samples--)
{
memory += ((*src++ - memory) * m_k) / 0x10000;
@@ -93,10 +94,21 @@ void filter_rc_device::recalc()
{
/* filter disabled */
m_k = 0x10000;
+ m_memory = 0x0;
return;
}
Req = (m_R1 * (m_R2 + m_R3)) / (m_R1 + m_R2 + m_R3);
break;
+ case LOWPASS_2C:
+ if (m_C == 0.0)
+ {
+ /* filter disabled */
+ m_k = 0x10000;
+ m_memory = 0x0;
+ return;
+ }
+ Req = m_R1;
+ break;
case HIGHPASS:
case AC:
if (m_C == 0.0)
diff --git a/src/devices/sound/flt_rc.h b/src/devices/sound/flt_rc.h
index 8e6057ceed0..cbf5772607e 100644
--- a/src/devices/sound/flt_rc.h
+++ b/src/devices/sound/flt_rc.h
@@ -18,6 +18,16 @@
*
* Set C=0 to disable filter
*
+ * FLT_RC_LOWPASS_@C:
+ *
+ * signal >--R1--+----> amp
+ * |
+ * C
+ * |
+ * GND
+ *
+ * Set C=0 to disable filter
+ *
* FLT_RC_HIGHPASS:
*
* signal >--C---+----> amp
@@ -53,8 +63,9 @@ public:
enum
{
LOWPASS = 0,
- HIGHPASS = 1,
- AC = 2
+ LOWPASS_2C = 2,
+ HIGHPASS = 3,
+ AC = 4
};
filter_rc_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock = 0);
@@ -70,6 +81,16 @@ public:
return *this;
}
+ filter_rc_device &set_lowpass(double R, double C)
+ {
+ m_type = LOWPASS_2C;
+ m_R1 = R;
+ m_R2 = 0;
+ m_R3 = 0;
+ m_C = C;
+ return *this;
+ }
+
filter_rc_device &filter_rc_set_RC(int type, double R1, double R2, double R3, double C)
{
m_stream->update();
diff --git a/src/devices/sound/votrax.cpp b/src/devices/sound/votrax.cpp
index 720df7d2ca9..8b416da6188 100644
--- a/src/devices/sound/votrax.cpp
+++ b/src/devices/sound/votrax.cpp
@@ -470,14 +470,17 @@ void votrax_sc01_device::chip_update()
// Pitch counter. Equality comparison, so it's possible to make
// it miss by manipulating the inflection inputs, but it'll wrap.
- // There's a delay, hence the +1.
- m_pitch = (m_pitch + 1) & 0x7f;
- if(m_pitch == (0x7f ^ (m_inflection << 4) ^ m_filt_f1) + 1)
+ // There's a delay, hence the +2.
+
+ // Intrinsically pre-divides by two, so we added one bit on the 7
+
+ m_pitch = (m_pitch + 1) & 0xff;
+ if(m_pitch == (0xe0 ^ (m_inflection << 5) ^ (m_filt_f1 << 1)) + 2)
m_pitch = 0;
// Filters are updated in index 1 of the pitch wave, which does
// indeed mean four times in a row.
- if((m_pitch >> 2) == 1)
+ if((m_pitch & 0xf9) == 0x08)
filters_commit(false);
// Noise shift register. 15 bits, with a nxor on the last two
@@ -486,7 +489,7 @@ void votrax_sc01_device::chip_update()
m_noise = ((m_noise << 1) & 0x7ffe) | inp;
m_cur_noise = !(((m_noise >> 14) ^ (m_noise >> 13)) & 1);
- // logerror("tick %02x.%03x 625=%d 208=%d pitch=%02x.%x ns=%04x ni=%d noise=%d cl=%x.%x clf=%d/%d\n", m_ticks, m_phonetick, tick_625, tick_208, m_pitch >> 2, m_pitch & 3, m_noise, inp, m_cur_noise, m_closure >> 2, m_closure & 3, m_rom_closure, m_cur_closure);
+ // logerror("%s tick %02x.%03x 625=%d 208=%d pitch=%02x.%x ns=%04x ni=%d noise=%d cl=%x.%x clf=%d/%d\n", machine().time().to_string(), m_ticks, m_phonetick, tick_625, tick_208, m_pitch >> 3, m_pitch & 7, m_noise, inp, m_cur_noise, m_closure >> 2, m_closure & 3, m_rom_closure, m_cur_closure);
}
void votrax_sc01_device::filters_commit(bool force)
@@ -570,7 +573,7 @@ stream_sample_t votrax_sc01_device::analog_calc()
// Voice-only path.
// 1. Pick up the pitch wave
- double v = m_pitch >= (9 << 2) ? 0 : s_glottal_wave[m_pitch >> 2];
+ double v = m_pitch >= (9 << 3) ? 0 : s_glottal_wave[m_pitch >> 3];
// 2. Multiply by the initial amplifier. It's linear on the die,
// even if it's not in the patent.
@@ -622,7 +625,7 @@ stream_sample_t votrax_sc01_device::analog_calc()
shift_hist(vn, m_vn_4);
// 13. Apply the glottal closure amplitude, also linear
- vn = vn * (7 ^ (m_cur_closure >> 2)) / 7.0;
+ vn = vn * (7 ^ (m_closure >> 2)) / 7.0;
shift_hist(vn, m_vn_5);
// 13. Apply the final fixed filter
diff --git a/src/mame/drivers/astrocde.cpp b/src/mame/drivers/astrocde.cpp
index cb8c2cb98ae..eda7f8b7c81 100644
--- a/src/mame/drivers/astrocde.cpp
+++ b/src/mame/drivers/astrocde.cpp
@@ -124,6 +124,7 @@
#include "machine/watchdog.h"
#include "sound/ay8910.h"
#include "sound/votrax.h"
+#include "sound/flt_rc.h"
#include "speaker.h"
@@ -397,10 +398,11 @@ void tenpindx_state::lights_w(uint8_t data)
void astrocde_state::votrax_speech_w(uint8_t data)
{
- m_votrax->inflection_w(data >> 6);
+ // Note that the frequency change is smooth, but we just can't
+ // handle that.
+ m_votrax->set_clock(data & 0x40 ? 782000 : 756000);
+ m_votrax->inflection_w(data & 0x80 ? 0 : 2);
m_votrax->write(data & 0x3f);
-
- /* Note : We should really also use volume in this as well as frequency */
}
@@ -1355,8 +1357,13 @@ void astrocde_state::wow(machine_config &config)
m_astrocade_sound1->so_cb<5>().set("outlatch", FUNC(cd4099_device::write_nibble_d0));
m_astrocade_sound1->so_cb<7>().set(FUNC(astrocde_state::votrax_speech_w));
- VOTRAX_SC01(config, m_votrax, 720000);
- m_votrax->add_route(ALL_OUTPUTS, "center", 0.85);
+ VOTRAX_SC01(config, m_votrax, 756000);
+
+ m_votrax->add_route(0, "f1", 0.85);
+ FILTER_RC(config, "f1").set_lowpass(110e3, 560e-12).add_route(0, "f2", 1.00);
+ FILTER_RC(config, "f2").set_lowpass(110e3, 560e-12).add_route(0, "f3", 1.00);
+ FILTER_RC(config, "f3").set_lowpass(110e3, 560e-12).add_route(0, "f4", 1.00);
+ FILTER_RC(config, "f4").set_lowpass(110e3, 560e-12).add_route(0, "center", 1.00);
}
void astrocde_state::gorf(machine_config &config)
@@ -1406,7 +1413,7 @@ void astrocde_state::gorf(machine_config &config)
ASTROCADE_IO(config, "astrocade2", ASTROCADE_CLOCK/4).add_route(ALL_OUTPUTS, "lower", 1.0);
- VOTRAX_SC01(config, m_votrax, 720000);
+ VOTRAX_SC01(config, m_votrax, 756000);
m_votrax->add_route(ALL_OUTPUTS, "upper", 0.85);
}