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-rw-r--r--src/mame/audio/n8080.c605
1 files changed, 605 insertions, 0 deletions
diff --git a/src/mame/audio/n8080.c b/src/mame/audio/n8080.c
new file mode 100644
index 00000000000..b6a820904bc
--- /dev/null
+++ b/src/mame/audio/n8080.c
@@ -0,0 +1,605 @@
+/***************************************************************************
+
+ Nintendo 8080 sound emulation
+
+***************************************************************************/
+
+#include "driver.h"
+#include "cpu/i8039/i8039.h"
+#include "sound/sn76477.h"
+#include "sound/dac.h"
+#include "includes/n8080.h"
+#include <math.h>
+
+static int n8080_hardware;
+
+static emu_timer* sound_timer[3];
+
+static int helifire_dac_phase;
+
+static const double ATTACK_RATE = 10e-6 * 500;
+static const double DECAY_RATE = 10e-6 * 16000;
+
+static double helifire_dac_volume;
+static double helifire_dac_timing;
+
+static UINT16 prev_sound_pins;
+static UINT16 curr_sound_pins;
+
+static int mono_flop[3];
+
+
+
+struct SN76477interface sheriff_sn76477_interface =
+{
+ RES_K(36) , /* 04 */
+ RES_K(100) , /* 05 */
+ CAP_N(1) , /* 06 */
+ RES_K(620) , /* 07 */
+ CAP_U(1) , /* 08 */
+ RES_K(20) , /* 10 */
+ RES_K(150) , /* 11 */
+ RES_K(47) , /* 12 */
+ 0 , /* 16 */
+ CAP_N(1) , /* 17 */
+ RES_M(1.5) , /* 18 */
+ 0 , /* 19 */
+ RES_M(1.5) , /* 20 */
+ CAP_N(47) , /* 21 */
+ CAP_N(47) , /* 23 */
+ RES_K(560) , /* 24 */
+ 0, /* 22 vco */
+ 0, /* 26 mixer A */
+ 0, /* 25 mixer B */
+ 0, /* 27 mixer C */
+ 1, /* 1 envelope 1 */
+ 0, /* 28 envelope 2 */
+ 1 /* 9 enable */
+};
+
+
+struct SN76477interface spacefev_sn76477_interface =
+{
+ RES_K(36) , /* 04 */
+ RES_K(150) , /* 05 */
+ CAP_N(1) , /* 06 */
+ RES_M(1) , /* 07 */
+ CAP_U(1) , /* 08 */
+ RES_K(20) , /* 10 */
+ RES_K(150) , /* 11 */
+ RES_K(47) , /* 12 */
+ 0 , /* 16 */
+ CAP_N(1) , /* 17 */
+ RES_M(1.5) , /* 18 */
+ 0 , /* 19 */
+ RES_M(1) , /* 20 */
+ CAP_N(47) , /* 21 */
+ CAP_N(47) , /* 23 */
+ RES_K(820) , /* 24 */
+ 0, /* 22 vco */
+ 0, /* 26 mixer A */
+ 0, /* 25 mixer B */
+ 0, /* 27 mixer C */
+ 1, /* 1 envelope 1 */
+ 0, /* 28 envelope 2 */
+ 1 /* 9 enable */
+};
+
+
+static void spacefev_update_SN76477_status(void)
+{
+ double dblR0 = RES_M(1.0);
+ double dblR1 = RES_M(1.5);
+
+ if (!mono_flop[0])
+ {
+ dblR0 = 1 / (1 / RES_K(150) + 1 / dblR0); /* ? */
+ }
+ if (!mono_flop[1])
+ {
+ dblR1 = 1 / (1 / RES_K(620) + 1 / dblR1); /* ? */
+ }
+
+ SN76477_decay_res_w(0, dblR0);
+
+ SN76477_vco_res_w(0, dblR1);
+
+ SN76477_enable_w(0,
+ !mono_flop[0] &&
+ !mono_flop[1] &&
+ !mono_flop[2]);
+
+ SN76477_vco_w(0, mono_flop[1]);
+
+ SN76477_mixer_b_w(0, mono_flop[0]);
+}
+
+
+static void sheriff_update_SN76477_status(void)
+{
+ if (mono_flop[1])
+ {
+ SN76477_vco_voltage_w(0, 5);
+ }
+ else
+ {
+ SN76477_vco_voltage_w(0, 0);
+ }
+
+ SN76477_enable_w(0,
+ !mono_flop[0] &&
+ !mono_flop[1]);
+
+ SN76477_vco_w(0, mono_flop[0]);
+
+ SN76477_mixer_b_w(0, !mono_flop[0]);
+}
+
+
+static void update_SN76477_status(void)
+{
+ if (n8080_hardware == 1)
+ {
+ spacefev_update_SN76477_status();
+ }
+ if (n8080_hardware == 2)
+ {
+ sheriff_update_SN76477_status();
+ }
+}
+
+
+static void start_mono_flop(int n, attotime expire)
+{
+ mono_flop[n] = 1;
+
+ update_SN76477_status();
+
+ timer_adjust(sound_timer[n], expire, n, attotime_zero);
+}
+
+
+static void stop_mono_flop(int n)
+{
+ mono_flop[n] = 0;
+
+ update_SN76477_status();
+
+ timer_adjust(sound_timer[n], attotime_never, n, attotime_never);
+}
+
+
+static TIMER_CALLBACK( stop_mono_flop_callback )
+{
+ stop_mono_flop(param);
+}
+
+
+static void spacefev_sound_pins_changed(void)
+{
+ UINT16 changes = ~curr_sound_pins & prev_sound_pins;
+
+ if (changes & (1 << 0x3))
+ {
+ stop_mono_flop(1);
+ }
+ if (changes & ((1 << 0x3) | (1 << 0x6)))
+ {
+ stop_mono_flop(2);
+ }
+ if (changes & (1 << 0x3))
+ {
+ start_mono_flop(0, ATTOTIME_IN_USEC(550 * 36 * 100));
+ }
+ if (changes & (1 << 0x6))
+ {
+ start_mono_flop(1, ATTOTIME_IN_USEC(550 * 22 * 33));
+ }
+ if (changes & (1 << 0x4))
+ {
+ start_mono_flop(2, ATTOTIME_IN_USEC(550 * 22 * 33));
+ }
+ if (changes & ((1 << 0x2) | (1 << 0x3) | (1 << 0x5)))
+ {
+ cpunum_set_input_line(1, 0, PULSE_LINE);
+ }
+}
+
+
+static void sheriff_sound_pins_changed(void)
+{
+ UINT16 changes = ~curr_sound_pins & prev_sound_pins;
+
+ if (changes & (1 << 0x6))
+ {
+ stop_mono_flop(1);
+ }
+ if (changes & (1 << 0x6))
+ {
+ start_mono_flop(0, ATTOTIME_IN_USEC(550 * 33 * 33));
+ }
+ if (changes & (1 << 0x4))
+ {
+ start_mono_flop(1, ATTOTIME_IN_USEC(550 * 33 * 33));
+ }
+ if (changes & ((1 << 0x2) | (1 << 0x3) | (1 << 0x5)))
+ {
+ cpunum_set_input_line(1, 0, PULSE_LINE);
+ }
+}
+
+
+static void helifire_sound_pins_changed(void)
+{
+ UINT16 changes = ~curr_sound_pins & prev_sound_pins;
+
+ /* ((curr_sound_pins >> 0xA) & 1) not emulated */
+ /* ((curr_sound_pins >> 0xB) & 1) not emulated */
+ /* ((curr_sound_pins >> 0xC) & 1) not emulated */
+
+ if (changes & (1 << 6))
+ {
+ cpunum_set_input_line(1, 0, PULSE_LINE);
+ }
+}
+
+
+static void sound_pins_changed(void)
+{
+ if (n8080_hardware == 1)
+ {
+ spacefev_sound_pins_changed();
+ }
+ if (n8080_hardware == 2)
+ {
+ sheriff_sound_pins_changed();
+ }
+ if (n8080_hardware == 3)
+ {
+ helifire_sound_pins_changed();
+ }
+
+ prev_sound_pins = curr_sound_pins;
+}
+
+
+static void delayed_sound_1(int data)
+{
+ static UINT8 prev_data = 0;
+
+ curr_sound_pins &= ~(
+ (1 << 0x7) |
+ (1 << 0x5) |
+ (1 << 0x6) |
+ (1 << 0x3) |
+ (1 << 0x4) |
+ (1 << 0x1));
+
+ if (~data & 0x01) curr_sound_pins |= 1 << 0x7;
+ if (~data & 0x02) curr_sound_pins |= 1 << 0x5; /* pulse */
+ if (~data & 0x04) curr_sound_pins |= 1 << 0x6; /* pulse */
+ if (~data & 0x08) curr_sound_pins |= 1 << 0x3; /* pulse (except in Helifire) */
+ if (~data & 0x10) curr_sound_pins |= 1 << 0x4; /* pulse (except in Helifire) */
+ if (~data & 0x20) curr_sound_pins |= 1 << 0x1;
+
+ if (n8080_hardware == 1)
+ {
+ if (data & ~prev_data & 0x10)
+ {
+ spacefev_start_red_cannon();
+ }
+
+ spacefev_red_screen = data & 0x08;
+ }
+
+ sound_pins_changed();
+
+ prev_data = data;
+}
+
+
+static TIMER_CALLBACK( delayed_sound_1_callback )
+{
+ delayed_sound_1(param);
+}
+
+
+static void delayed_sound_2(int data)
+{
+ curr_sound_pins &= ~(
+ (1 << 0x8) |
+ (1 << 0x9) |
+ (1 << 0xA) |
+ (1 << 0xB) |
+ (1 << 0x2) |
+ (1 << 0xC));
+
+ if (~data & 0x01) curr_sound_pins |= 1 << 0x8;
+ if (~data & 0x02) curr_sound_pins |= 1 << 0x9;
+ if (~data & 0x04) curr_sound_pins |= 1 << 0xA;
+ if (~data & 0x08) curr_sound_pins |= 1 << 0xB;
+ if (~data & 0x10) curr_sound_pins |= 1 << 0x2; /* pulse */
+ if (~data & 0x20) curr_sound_pins |= 1 << 0xC;
+
+ if (n8080_hardware == 1)
+ {
+ flip_screen = data & 0x20;
+ }
+ if (n8080_hardware == 3)
+ {
+ helifire_flash = data & 0x20;
+ }
+
+ sound_pins_changed();
+}
+
+
+static TIMER_CALLBACK( delayed_sound_2_callback )
+{
+ delayed_sound_2(param);
+}
+
+
+WRITE8_HANDLER( n8080_sound_1_w )
+{
+ timer_call_after_resynch(data, delayed_sound_1_callback); /* force CPUs to sync */
+}
+WRITE8_HANDLER( n8080_sound_2_w )
+{
+ timer_call_after_resynch(data, delayed_sound_2_callback); /* force CPUs to sync */
+}
+
+
+static READ8_HANDLER( n8080_8035_p1_r )
+{
+ UINT8 val = 0;
+
+ if ((curr_sound_pins >> 0xB) & 1) val |= 0x01;
+ if ((curr_sound_pins >> 0xA) & 1) val |= 0x02;
+ if ((curr_sound_pins >> 0x9) & 1) val |= 0x04;
+ if ((curr_sound_pins >> 0x8) & 1) val |= 0x08;
+ if ((curr_sound_pins >> 0x5) & 1) val |= 0x10;
+ if ((curr_sound_pins >> 0x3) & 1) val |= 0x20;
+ if ((curr_sound_pins >> 0x2) & 1) val |= 0x40;
+ if ((curr_sound_pins >> 0x1) & 1) val |= 0x80;
+
+ return val;
+}
+
+
+static READ8_HANDLER( n8080_8035_t0_r )
+{
+ return (curr_sound_pins >> 0x7) & 1;
+}
+static READ8_HANDLER( n8080_8035_t1_r )
+{
+ return (curr_sound_pins >> 0xC) & 1;
+}
+
+
+static READ8_HANDLER( helifire_8035_t0_r )
+{
+ return (curr_sound_pins >> 0x3) & 1;
+}
+static READ8_HANDLER( helifire_8035_t1_r )
+{
+ return (curr_sound_pins >> 0x4) & 1;
+}
+
+
+static READ8_HANDLER( helifire_8035_external_ram_r )
+{
+ UINT8 val = 0;
+
+ if ((curr_sound_pins >> 0x7) & 1) val |= 0x01;
+ if ((curr_sound_pins >> 0x8) & 1) val |= 0x02;
+ if ((curr_sound_pins >> 0x9) & 1) val |= 0x04;
+ if ((curr_sound_pins >> 0x1) & 1) val |= 0x08;
+
+ return val;
+}
+
+
+static READ8_HANDLER( helifire_8035_p2_r )
+{
+ return ((curr_sound_pins >> 0xC) & 1) ? 0x10 : 0x00; /* not used */
+}
+
+
+static WRITE8_HANDLER( n8080_dac_w )
+{
+ DAC_data_w(0, data & 0x80);
+}
+
+
+static WRITE8_HANDLER( helifire_dac_w )
+{
+ DAC_data_w(0, data * helifire_dac_volume);
+}
+
+
+static WRITE8_HANDLER( helifire_sound_ctrl_w )
+{
+ helifire_dac_phase = data & 0x80;
+
+ /* data & 0x40 not emulated */
+ /* data & 0x20 not emulated */
+
+ if (helifire_dac_phase)
+ {
+ helifire_dac_timing = ATTACK_RATE * log(1 - helifire_dac_volume);
+ }
+ else
+ {
+ helifire_dac_timing = DECAY_RATE * log(helifire_dac_volume);
+ }
+
+ helifire_dac_timing += attotime_to_double(timer_get_time());
+}
+
+
+static TIMER_CALLBACK( spacefev_vco_voltage_timer )
+{
+ double voltage = 0;
+
+ if (mono_flop[2])
+ {
+ voltage = 5 * (1 - exp(- attotime_to_double(timer_timeelapsed(sound_timer[2])) / 0.22));
+ }
+
+ SN76477_vco_voltage_w(0, voltage);
+}
+
+
+static TIMER_CALLBACK( helifire_dac_volume_timer )
+{
+ double t = helifire_dac_timing - attotime_to_double(timer_get_time());
+
+ if (helifire_dac_phase)
+ {
+ helifire_dac_volume = 1 - exp(t / ATTACK_RATE);
+ }
+ else
+ {
+ helifire_dac_volume = exp(t / DECAY_RATE);
+ }
+}
+
+
+static MACHINE_RESET( spacefev_sound )
+{
+ n8080_hardware = 1;
+
+ timer_pulse(ATTOTIME_IN_HZ(1000), 0, spacefev_vco_voltage_timer);
+
+ sound_timer[0] = timer_alloc(stop_mono_flop_callback);
+ sound_timer[1] = timer_alloc(stop_mono_flop_callback);
+ sound_timer[2] = timer_alloc(stop_mono_flop_callback);
+
+ mono_flop[0] = 0;
+ mono_flop[1] = 0;
+ mono_flop[2] = 0;
+
+ delayed_sound_1(0);
+ delayed_sound_2(0);
+}
+
+
+static MACHINE_RESET( sheriff_sound )
+{
+ n8080_hardware = 2;
+
+ sound_timer[0] = timer_alloc(stop_mono_flop_callback);
+ sound_timer[1] = timer_alloc(stop_mono_flop_callback);
+
+ mono_flop[0] = 0;
+ mono_flop[1] = 0;
+
+ delayed_sound_1(0);
+ delayed_sound_2(0);
+}
+
+
+static MACHINE_RESET( helifire_sound )
+{
+ n8080_hardware = 3;
+
+ timer_pulse(ATTOTIME_IN_HZ(1000), 0, helifire_dac_volume_timer);
+
+ helifire_dac_volume = 1;
+ helifire_dac_timing = 0;
+
+ delayed_sound_1(0);
+ delayed_sound_2(0);
+
+ helifire_dac_phase = 0;
+}
+
+
+static ADDRESS_MAP_START( n8080_sound_cpu_map, ADDRESS_SPACE_PROGRAM, 8 )
+ ADDRESS_MAP_FLAGS( AMEF_ABITS(10) )
+ AM_RANGE(0x0000, 0x03ff) AM_ROM
+ADDRESS_MAP_END
+
+
+static ADDRESS_MAP_START( n8080_sound_io_map, ADDRESS_SPACE_IO, 8 )
+ AM_RANGE(I8039_t0, I8039_t0) AM_READ(n8080_8035_t0_r)
+ AM_RANGE(I8039_t1, I8039_t1) AM_READ(n8080_8035_t1_r)
+ AM_RANGE(I8039_p1, I8039_p1) AM_READ(n8080_8035_p1_r)
+
+ AM_RANGE(I8039_p2, I8039_p2) AM_WRITE(n8080_dac_w)
+ADDRESS_MAP_END
+
+
+static ADDRESS_MAP_START( helifire_sound_io_map, ADDRESS_SPACE_IO, 8 )
+ AM_RANGE(I8039_t0, I8039_t0) AM_READ(helifire_8035_t0_r)
+ AM_RANGE(I8039_t1, I8039_t1) AM_READ(helifire_8035_t1_r)
+ AM_RANGE(I8039_p2, I8039_p2) AM_READ(helifire_8035_p2_r)
+
+ AM_RANGE(0x00, 0x7f) AM_READ(helifire_8035_external_ram_r)
+
+ AM_RANGE(I8039_p1, I8039_p1) AM_WRITE(helifire_dac_w)
+ AM_RANGE(I8039_p2, I8039_p2) AM_WRITE(helifire_sound_ctrl_w)
+ADDRESS_MAP_END
+
+
+MACHINE_DRIVER_START( spacefev_sound )
+
+ /* basic machine hardware */
+ MDRV_CPU_ADD(I8035, 6000000 / I8039_CLOCK_DIVIDER)
+ /* audio CPU */
+ MDRV_CPU_PROGRAM_MAP(n8080_sound_cpu_map, 0)
+ MDRV_CPU_IO_MAP(n8080_sound_io_map, 0)
+
+ MDRV_MACHINE_RESET(spacefev_sound)
+
+ /* sound hardware */
+ MDRV_SPEAKER_STANDARD_MONO("mono")
+
+ MDRV_SOUND_ADD(DAC, 0)
+ MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.30)
+
+ MDRV_SOUND_ADD(SN76477, 0)
+ MDRV_SOUND_CONFIG(spacefev_sn76477_interface)
+ MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.35)
+MACHINE_DRIVER_END
+
+
+MACHINE_DRIVER_START( sheriff_sound )
+
+ /* basic machine hardware */
+ MDRV_CPU_ADD(I8035, 6000000 / I8039_CLOCK_DIVIDER)
+ /* audio CPU */
+ MDRV_CPU_PROGRAM_MAP(n8080_sound_cpu_map, 0)
+ MDRV_CPU_IO_MAP(n8080_sound_io_map, 0)
+
+ MDRV_MACHINE_RESET(sheriff_sound)
+
+ /* sound hardware */
+ MDRV_SPEAKER_STANDARD_MONO("mono")
+
+ MDRV_SOUND_ADD(DAC, 0)
+ MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.30)
+
+ MDRV_SOUND_ADD(SN76477, 0)
+ MDRV_SOUND_CONFIG(sheriff_sn76477_interface)
+ MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.35)
+MACHINE_DRIVER_END
+
+
+MACHINE_DRIVER_START( helifire_sound )
+
+ /* basic machine hardware */
+ MDRV_CPU_ADD(I8035, 6000000 / I8039_CLOCK_DIVIDER)
+ /* audio CPU */
+ MDRV_CPU_PROGRAM_MAP(n8080_sound_cpu_map, 0)
+ MDRV_CPU_IO_MAP(helifire_sound_io_map, 0)
+
+ MDRV_MACHINE_RESET(helifire_sound)
+
+ /* sound hardware */
+ MDRV_SPEAKER_STANDARD_MONO("mono")
+
+ MDRV_SOUND_ADD(DAC, 0)
+ MDRV_SOUND_ROUTE(ALL_OUTPUTS, "mono", 0.30)
+MACHINE_DRIVER_END