/* 8080bw.c *********************************
*/
#include "driver.h"
#include "8080bw.h"
#include "mw8080bw.h"
#include "sound/samples.h"
#include "sound/sn76477.h"
#include "sound/discrete.h"
#include "sound/speaker.h"
static emu_timer *schaser_effect_555_timer;
static attotime schaser_effect_555_time_remain;
static int schaser_effect_555_is_low;
static int schaser_explosion;
static UINT8 port_1_last = 0;
static UINT8 port_2_last = 0;
static UINT8 port_3_last = 0;
/*******************************************************/
/* */
/* Midway "Space Invaders Part II" */
/* */
/*******************************************************/
WRITE8_HANDLER( invadpt2_sh_port_1_w )
{
UINT8 rising_bits = data & ~port_1_last;
SN76477_enable_w(0, !(data & 0x01)); /* SAUCER SOUND */
if (rising_bits & 0x02) sample_start_n(0, 0, 0, 0); /* MISSLE SOUND */
if (rising_bits & 0x04) sample_start_n(0, 1, 1, 0); /* EXPLOSION */
if (rising_bits & 0x08) sample_start_n(0, 2, 2, 0); /* INVADER HIT */
if (rising_bits & 0x10) sample_start_n(0, 5, 8, 0); /* BONUS MISSILE BASE */
c8080bw_screen_red_w(data & 0x04);
sound_global_enable(data & 0x20);
port_1_last = data;
}
WRITE8_HANDLER( invadpt2_sh_port_2_w )
{
/* FLEET (movement)
DO = 20K + 20K
D1 = 68K
D2 = 82K
D3 = 100K */
UINT8 rising_bits = data & ~port_2_last;
if (rising_bits & 0x01) sample_start_n(0, 4, 3, 0); /* FLEET */
if (rising_bits & 0x02) sample_start_n(0, 4, 4, 0); /* FLEET */
if (rising_bits & 0x04) sample_start_n(0, 4, 5, 0); /* FLEET */
if (rising_bits & 0x08) sample_start_n(0, 4, 6, 0); /* FLEET */
if (rising_bits & 0x10) sample_start_n(0, 3, 7, 0); /* SAUCER HIT */
c8080bw_flip_screen_w(data & 0x20);
port_2_last = data;
}
/*******************************************************/
/* */
/* Sanritsu "Space War" */
/* */
/*******************************************************/
WRITE8_HANDLER( spcewars_sh_port_w )
{
UINT8 rising_bits = data & ~port_1_last;
SN76477_enable_w(0, !(data & 0x01)); /* Saucer Sound */
if (rising_bits & 0x02) sample_start(0, 0, 0); /* Shot Sound */
if (rising_bits & 0x04) sample_start(1, 1, 0); /* Base Hit */
if (rising_bits & 0x08) sample_start(2, 2, 0); /* Invader Hit */
speaker_level_w(0, (data & 0x10) ? 1 : 0); /* Various bitstream tunes */
port_1_last = data;
}
/*******************************************************/
/* */
/* lrescue, grescue, lrescuem, desterth */
/* */
/*******************************************************/
static const char *lrescue_sample_names[] =
{
"*lrescue",
"alienexplosion.wav",
"rescueshipexplosion.wav",
"beamgun.wav",
"thrust.wav",
"bonus2.wav",
"bonus3.wav",
"shootingstar.wav",
"stepl.wav",
"steph.wav",
0
};
struct Samplesinterface lrescue_samples_interface =
{
4, /* 4 channels */
lrescue_sample_names
};
WRITE8_HANDLER( lrescue_sh_port_1_w )
{
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(0, 3, 0); /* Thrust */
if (rising_bits & 0x02) sample_start(1, 2, 0); /* Shot Sound */
if (rising_bits & 0x04) sample_start(0, 1, 0); /* Death */
if (rising_bits & 0x08) sample_start(1, 0, 0); /* Alien Hit */
if (rising_bits & 0x10) sample_start(2, 5, 0); /* Bonus Ship (not confirmed) */
sound_global_enable(data & 0x20);
c8080bw_screen_red_w(data & 0x04);
port_1_last = data;
}
WRITE8_HANDLER( lrescue_sh_port_2_w )
{
UINT8 rising_bits = data & ~port_2_last;
if (rising_bits & 0x01) sample_start(1, 8, 0); /* Footstep high tone */
if (rising_bits & 0x02) sample_start(1, 7, 0); /* Footstep low tone */
if (rising_bits & 0x04) sample_start(1, 4, 0); /* Bonus when counting men saved */
speaker_level_w(0, (data & 0x08) ? 1 : 0); /* Bitstream tunes - endlevel and bonus1 */
if (rising_bits & 0x10) sample_start(3, 6, 0); /* Shooting Star and Rescue Ship sounds */
if (~data & 0x10 && port_2_last & 0x10) sample_stop (3); /* This makes the rescue ship sound beep on and off */
c8080bw_flip_screen_w(data & 0x20);
port_2_last = data;
}
/*******************************************************/
/* */
/* Cosmo */
/* */
/*******************************************************/
WRITE8_HANDLER( cosmo_sh_port_2_w )
{
/* inverted flip screen bit */
invadpt2_sh_port_2_w(offset, data ^ 0x20);
}
/*******************************************************/
/* */
/* Taito "Balloon Bomber" */
/* The sounds are not the correct ones */
/* */
/*******************************************************/
WRITE8_HANDLER( ballbomb_sh_port_1_w )
{
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(1, 2, 0); /* Hit a balloon */
if (rising_bits & 0x02) sample_start(2, 0, 0); /* Shot Sound */
if (rising_bits & 0x04) sample_start(2, 1, 0); /* Base Hit */
if (rising_bits & 0x08) sample_start(1, 7, 0); /* Hit a Bomb */
if (rising_bits & 0x10) sample_start(3, 8, 0); /* Bonus Base at 1500 points */
sound_global_enable(data & 0x20);
c8080bw_screen_red_w(data & 0x04);
port_1_last = data;
}
WRITE8_HANDLER( ballbomb_sh_port_2_w )
{
UINT8 rising_bits = data & ~port_2_last;
if (data & 0x01) sample_start(0, 7, 0); /* Indicates plane will drop bombs */
if (data & 0x04) sample_start(0, 4, 0); /* Plane is dropping new balloons at start of level */
if (rising_bits & 0x10) sample_start(2, 2, 0); /* Balloon hit and bomb drops */
c8080bw_flip_screen_w(data & 0x20);
port_2_last = data;
}
/*******************************************************/
/* */
/* Taito "Indian Battle" */
/* Sept 2005, D.R. */
/*******************************************************/
static const discrete_dac_r1_ladder indianbt_music_dac =
{3, {0, RES_K(47), RES_K(12)}, 0, 0, 0, CAP_U(0.1)};
#define INDIANBT_MUSIC_CLK (7680.0*2*2*2)
/* Nodes - Inputs */
#define INDIANBT_MUSIC_DATA NODE_01
/* Nodes - Sounds */
#define INDIANBT_MUSIC NODE_11
DISCRETE_SOUND_START(indianbt)
DISCRETE_INPUT_DATA (INDIANBT_MUSIC_DATA)
/******************************************************************************
*
* Music Generator
*
******************************************************************************/
DISCRETE_NOTE(NODE_20, 1, INDIANBT_MUSIC_CLK, INDIANBT_MUSIC_DATA, 255, 5, DISC_CLK_IS_FREQ)
// Convert count to 7492 output
DISCRETE_TRANSFORM2(NODE_21, 1, NODE_20, 2, "01>0+")
DISCRETE_DAC_R1(NODE_22, 1, NODE_21, DEFAULT_TTL_V_LOGIC_1, &indianbt_music_dac)
/******************************************************************************
*
* Final Mixing and Output
*
******************************************************************************/
DISCRETE_CRFILTER(NODE_90, 1, NODE_22, RES_K(10), CAP_U(0.1))
DISCRETE_OUTPUT(NODE_90, 21000)
DISCRETE_SOUND_END
WRITE8_HANDLER( indianbt_sh_port_1_w )
{
/* bit 4 occurs every 5.25 seconds during gameplay */
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(1, 7, 0); /* Death */
if (rising_bits & 0x02) sample_start(0, 1, 0); /* Shot Sound */
if (rising_bits & 0x04) sample_start(2, 3, 0); /* Move */
if (rising_bits & 0x08) sample_start(3, 2, 0); /* Hit */
sound_global_enable(data & 0x20);
c8080bw_screen_red_w(data & 0x01);
port_1_last = data;
}
WRITE8_HANDLER( indianbt_sh_port_2_w )
{
UINT8 rising_bits = data & ~port_2_last;
if (rising_bits & 0x01) sample_start(4, 0, 0); /* Bird dropped an egg, Lasso used */
if (rising_bits & 0x02) sample_start(4, 2, 0); /* Egg hatches, egg shot */
if (rising_bits & 0x08) sample_start(5, 0, 0); /* Grabber, Lasso caught something */
if (rising_bits & 0x10) sample_start(3, 7, 0); /* Lasso sound */
port_2_last = data;
}
WRITE8_HANDLER( indianbt_sh_port_3_w )
{
discrete_sound_w(INDIANBT_MUSIC_DATA, data);
}
/*******************************************************************/
/* */
/* Taito "Polaris" */
/* */
/* D.R. */
/* The R/C values in the schematic may have no bearing in reality. */
/* I have noted some differences from a real board. */
/* */
/*******************************************************************/
static const discrete_lfsr_desc polaris_lfsr={
DISC_CLK_IS_FREQ,
17, /* Bit Length */
0, /* Reset Value */
4, /* Use Bit 4 as XOR input 0 */
16, /* Use Bit 16 as XOR input 1 */
DISC_LFSR_XOR, /* Feedback stage1 is XOR */
DISC_LFSR_OR, /* Feedback stage2 is just stage 1 output OR with external feed */
DISC_LFSR_REPLACE, /* Feedback stage3 replaces the shifted register contents */
0x000001, /* Everything is shifted into the first bit only */
0, /* Output is not inverted */
12 /* Output bit */
};
static const discrete_dac_r1_ladder polaris_music_dac =
{2, {RES_K(47), RES_K(12), 0,0,0,0,0,0}, 0, 0, 0, CAP_P(180)};
static const discrete_op_amp_filt_info polaris_music_op_amp_filt_info =
{RES_K(580), 0, 0, RES_M(2.2), RES_M(1), CAP_U(.01), 0, 0, 0, 12, 0};
static const discrete_op_amp_filt_info polaris_nol_op_amp_filt_info =
{560, RES_K(6.8), RES_K(1002), RES_M(2.2), RES_M(1), CAP_U(.22), CAP_U(.22), CAP_U(1), 0, 12, 0};
static const discrete_op_amp_filt_info polaris_noh_op_amp_filt_info =
{560, RES_K(6.8), RES_K(1002), RES_M(2.2), RES_M(1), CAP_U(.001), CAP_U(.001), CAP_U(.01), 0, 12, 0};
static const discrete_op_amp_osc_info polaris_sonar_vco_info =
{DISC_OP_AMP_OSCILLATOR_VCO_1 | DISC_OP_AMP_IS_NORTON | DISC_OP_AMP_OSCILLATOR_OUT_CAP, RES_M(1), RES_K(680), RES_K(680), RES_M(1), RES_M(1), RES_K(120), RES_M(1), 0, CAP_P(180), 12};
static const discrete_op_amp_tvca_info polaris_sonar_tvca_info =
{ RES_M(2.7), RES_K(680), 0, RES_K(680), RES_K(1), RES_K(120), RES_K(560), 0, 0, 0, 0, CAP_U(1), 0, 0, 12, 12, 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_TRG1, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0_INV, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE};
static const discrete_op_amp_osc_info polaris_boat_mod_info =
{DISC_OP_AMP_OSCILLATOR_1 | DISC_OP_AMP_IS_NORTON | DISC_OP_AMP_OSCILLATOR_OUT_CAP, RES_M(1), RES_K(10), RES_K(100), RES_K(120), RES_M(1), 0, 0, 0, CAP_U(.22), 12};
static const discrete_op_amp_osc_info polaris_boat_vco_info =
{DISC_OP_AMP_OSCILLATOR_VCO_1 | DISC_OP_AMP_IS_NORTON | DISC_OP_AMP_OSCILLATOR_OUT_CAP, RES_M(1), RES_K(680), RES_K(680), RES_M(1), RES_M(1), 0, 0, 0, CAP_P(180), 12};
static const discrete_op_amp_tvca_info polaris_shot_tvca_info =
{ RES_M(2.7), RES_K(680), RES_K(680), RES_K(680), RES_K(1), 0, RES_K(680), 0, 0, 0, 0, CAP_U(1), 0, 0, 12, 12, 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0_INV, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE};
static const discrete_op_amp_tvca_info polaris_shiphit_tvca_info =
{ RES_M(2.7), RES_K(680), RES_K(680), RES_K(680), RES_K(1), 0, RES_K(680), 0, 0, 0, 0, CAP_U(1), 0, 0, 12, 12, 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0_INV, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE};
static const discrete_op_amp_tvca_info polaris_exp_tvca_info =
{ RES_M(2.7), RES_K(680), 0, RES_K(680), RES_K(1), 0, RES_K(680), 0, 0, 0, 0, CAP_U(.33), 0, 0, 12, 12, 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE};
// The schematic shows a .22uF cap but Guru's board has a 1uF
static const discrete_op_amp_tvca_info polaris_hit_tvca_info =
{ RES_M(2.7), RES_K(1360), RES_K(1360), RES_K(680), RES_K(1), 0, RES_K(680), 0, 0, 0, 0, CAP_U(1), 0, 0, 12, 12, 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_TRG1, DISC_OP_AMP_TRIGGER_FUNCTION_TRG01_NAND, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE, DISC_OP_AMP_TRIGGER_FUNCTION_NONE};
// The schematic shows a 1uF cap but Guru's board has a 2.2uF
static const discrete_integrate_info polaris_plane_integrate_info =
{DISC_INTEGRATE_OP_AMP_2 | DISC_OP_AMP_IS_NORTON, RES_K(1001), RES_K(1001), RES_K(101), CAP_U(2.2), 12, 12, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0, DISC_OP_AMP_TRIGGER_FUNCTION_TRG0_INV, DISC_OP_AMP_TRIGGER_FUNCTION_TRG1_INV};
// A bit of a cheat. The schematic show the cap as 47p, but that makes the frequency too high.
// Guru's board has a .01 cap, which would make the freq sub-sonic using the other schematic values.
// I will use 2000p until the proper values can be confirmed.
static const discrete_op_amp_osc_info polaris_plane_vco_info =
{DISC_OP_AMP_OSCILLATOR_VCO_1 | DISC_OP_AMP_IS_NORTON | DISC_OP_AMP_OSCILLATOR_OUT_CAP, RES_M(1), RES_K(680), RES_K(680), RES_M(1), RES_M(1), RES_K(100), RES_K(10), RES_K(100), CAP_U(0.002), 12};
static const discrete_mixer_desc polaris_mixer_vr1_desc =
{DISC_MIXER_IS_RESISTOR,
{RES_K(66), RES_K(43), RES_K(20), RES_K(43)},
{0}, // no variable resistors
{CAP_U(1), CAP_U(1), CAP_U(1), CAP_U(1)},
0, RES_K(50), 0, 0, 0, 1};
static const discrete_mixer_desc polaris_mixer_vr2_desc =
{DISC_MIXER_IS_RESISTOR,
{RES_K(66), RES_K(110)},
{0}, // no variable resistors
{CAP_U(1), CAP_U(1)},
0, RES_K(50), 0, 0, 0, 1};
// Note: the final gain leaves the explosions (SX3) at a level
// where they clip. From the schematics, this is how they wanted it.
// This makes them have more bass and distortion.
static const discrete_mixer_desc polaris_mixer_vr4_desc =
{DISC_MIXER_IS_RESISTOR,
{RES_K(22), RES_K(20), RES_K(22), RES_K(22)},
{0}, // no variable resistors
{0, CAP_U(1), 0, 0},
0, RES_K(50), 0, CAP_U(1), 0, 40000};
/* Nodes - Inputs */
#define POLARIS_MUSIC_DATA NODE_01
#define POLARIS_SX0_EN NODE_02
#define POLARIS_SX1_EN NODE_03
#define POLARIS_SX2_EN NODE_04
#define POLARIS_SX3_EN NODE_05
#define POLARIS_SX5_EN NODE_06
#define POLARIS_SX6_EN NODE_07
#define POLARIS_SX7_EN NODE_08
#define POLARIS_SX9_EN NODE_09
#define POLARIS_SX10_EN NODE_10
/* Nodes - Sounds */
#define POLARIS_MUSIC NODE_11
#define POLARIS_NOISE_LO NODE_12
#define POLARIS_NOISE_LO_FILT NODE_13
#define POLARIS_NOISE_HI_FILT NODE_14
#define POLARIS_SHOTSND NODE_15
#define POLARIS_SHIP_HITSND NODE_16
#define POLARIS_SHIPSND NODE_17
#define POLARIS_EXPLOSIONSND NODE_18
#define POLARIS_PLANESND NODE_19
#define POLARIS_HITSND NODE_20
#define POLARIS_SONARSND NODE_21
/* Nodes - Adjust */
#define POLARIS_ADJ_VR1 NODE_23
#define POLARIS_ADJ_VR2 NODE_24
#define POLARIS_ADJ_VR3 NODE_25
DISCRETE_SOUND_START(polaris)
/************************************************/
/* Polaris sound system: 8 Sound Sources */
/* */
/* Relative volumes are adjustable */
/* */
/************************************************/
/************************************************/
/* Input register mapping for polaris */
/************************************************/
DISCRETE_INPUT_DATA (POLARIS_MUSIC_DATA)
DISCRETE_INPUT_LOGIC(POLARIS_SX0_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX1_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX2_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX3_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX5_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX6_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX7_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX9_EN)
DISCRETE_INPUT_LOGIC(POLARIS_SX10_EN)
/* We will cheat and just use the controls to scale the amplitude. */
/* It is the same as taking the (0 to 50k)/50k */
DISCRETE_ADJUSTMENT_TAG(POLARIS_ADJ_VR1, 1, 0, 1, DISC_LINADJ, "VR1")
DISCRETE_ADJUSTMENT_TAG(POLARIS_ADJ_VR2, 1, 0, 1, DISC_LINADJ, "VR2")
/* Extra cheating for VR3. We will include the resistor scaling. */
DISCRETE_ADJUSTMENT_TAG(POLARIS_ADJ_VR3, 1, 0, 0.5376, DISC_LINADJ, "VR3")
/******************************************************************************
*
* Music Generator
*
* This is a simulation of the following circuit:
* 555 Timer (Ra = 1k, Rb = 1k, C =.01uF) running at 48kHz. Connected to a
* 1 bit counter (/2) for 24kHz. But I will use the frequency measured by Guru.
* This is then sent to a preloadable 8 bit counter (4G & 4H), which loads the
* value from Port 2 when overflowing from 0xFF to 0x00. Therefore it divides
* by 2 (Port 2 = FE) to 256 (Port 2 = 00).
* This goes to a 2 bit counter (5H) which has a 47k resistor on Q0 and a 12k on Q1.
* This creates a sawtooth ramp of: 0%, 12/59%, 47/59%, 100% then back to 0%
*
* Note that there is no music disable line. When there is no music, the game
* sets the oscillator to 0Hz. (Port 2 = FF)
*
******************************************************************************/
DISCRETE_NOTE(NODE_30, 1, 23396, POLARIS_MUSIC_DATA, 255, 3, DISC_CLK_IS_FREQ)
DISCRETE_DAC_R1(NODE_31, 1, NODE_30, DEFAULT_TTL_V_LOGIC_1, &polaris_music_dac)
DISCRETE_OP_AMP_FILTER(NODE_32, 1, NODE_31, 0, DISC_OP_AMP_FILTER_IS_HIGH_PASS_0 | DISC_OP_AMP_IS_NORTON, &polaris_music_op_amp_filt_info)
DISCRETE_MULTIPLY(POLARIS_MUSIC, 1, NODE_32, POLARIS_ADJ_VR3)
/******************************************************************************
*
* Background Sonar Sound
*
* This is a background sonar that plays at all times during the game.
* It is a VCO triangle wave genarator, that uses the Low frequency filtered
* noise source to modulate the frequency.
* This is then amplitude modulated, by some fancy clocking scheme.
* It is disabled during SX3. (No sonar when you die.)
*
* 5L pin 6 divides 60Hz by 16. This clocks the sonar.
* 5K pin 9 is inverted by 5F, and then the 0.1uF;1M;270k;1S1588 diode circuit
* makes a one shot pulse of approx. 15ms to keep the noise working.
*
******************************************************************************/
DISCRETE_SQUAREWFIX(NODE_40, 1, 60.0/16, 1, 50, 1.0/2, 0) // IC 5L, pin 6
DISCRETE_COUNTER(NODE_41, 1, 0, NODE_40, 31, 1, 0, DISC_CLK_ON_F_EDGE) // IC 5L & 5F
DISCRETE_TRANSFORM2(NODE_42, 1, NODE_41, 4, "01&") // IC 5L, pin 9
DISCRETE_TRANSFORM2(NODE_43, 1, NODE_41, 16, "01&!") // IC 5F, pin 8
DISCRETE_ONESHOT(NODE_44, NODE_43, 1, 0.0015, DISC_ONESHOT_REDGE | DISC_ONESHOT_NORETRIG | DISC_OUT_ACTIVE_HIGH)
DISCRETE_LOGIC_OR(NODE_45, 1, NODE_42, POLARIS_SX3_EN)
DISCRETE_LOGIC_DFLIPFLOP(NODE_46, 1, 1, 1, NODE_40, NODE_45)
DISCRETE_OP_AMP_VCO1(NODE_47, 1, POLARIS_NOISE_LO_FILT, &polaris_sonar_vco_info)
DISCRETE_OP_AMP_TRIG_VCA(POLARIS_SONARSND, NODE_45, NODE_46, 0, NODE_47, 0, &polaris_sonar_tvca_info)
/******************************************************************************
*
* Noise sources
*
* The frequencies for the noise sources were Measured by Guru.
*
* The output of the shift register is buffered by an op-amp which limits
* the output to 0V and (12V - OP_AMP_NORTON_VBE)
*
******************************************************************************/
DISCRETE_LFSR_NOISE(POLARIS_NOISE_LO, 1, 1, 800.8, (12.0 - OP_AMP_NORTON_VBE), NODE_44, (12.0 - OP_AMP_NORTON_VBE)/2, &polaris_lfsr) // Unfiltered Lo noise. 7K pin 4.
// Filtered Lo noise. 7K pin 5.
DISCRETE_OP_AMP_FILTER(POLARIS_NOISE_LO_FILT, 1, POLARIS_NOISE_LO, 0, DISC_OP_AMP_FILTER_IS_BAND_PASS_0 | DISC_OP_AMP_IS_NORTON, &polaris_nol_op_amp_filt_info)
DISCRETE_LFSR_NOISE(NODE_50, 1, 1, 23396, (12.0 - OP_AMP_NORTON_VBE), NODE_44, (12.0 - OP_AMP_NORTON_VBE)/2, &polaris_lfsr) // 7K pin 10
// Filtered Hi noise. 6B pin 10. - This does not really do much. Sample rates of 98k+ are needed for this high of filtering.
DISCRETE_OP_AMP_FILTER(POLARIS_NOISE_HI_FILT, 1, NODE_50, 0, DISC_OP_AMP_FILTER_IS_BAND_PASS_0 | DISC_OP_AMP_IS_NORTON, &polaris_noh_op_amp_filt_info)
/******************************************************************************
*
* Shot - SX0 (When player shoots)
*
* When Enabled it makes a low frequency RC filtered noise. As soon as it
* disables, it switches to a high frequency RC filtered noise with the volume
* decaying based on the RC values of 680k and 1uF.
*
******************************************************************************/
DISCRETE_OP_AMP_TRIG_VCA(POLARIS_SHOTSND, POLARIS_SX0_EN, 0, 0, POLARIS_NOISE_HI_FILT, POLARIS_NOISE_LO_FILT, &polaris_shot_tvca_info)
/******************************************************************************
*
* Ship Hit - SX1 (When sub is hit)
*
* When Enabled it makes a low frequency RC filtered noise. As soon as it
* disables, it's volume starts decaying based on the RC values of 680k and
* 1uF. Also as it decays, a decaying high frequency RC filtered noise is
* mixed in.
*
******************************************************************************/
DISCRETE_OP_AMP_TRIG_VCA(POLARIS_SHIP_HITSND, POLARIS_SX1_EN, 0, 0, POLARIS_NOISE_HI_FILT, POLARIS_NOISE_LO_FILT, &polaris_shiphit_tvca_info)
/******************************************************************************
*
* Ship - SX2 (When boat moves across screen)
*
* This uses a 5.75Hz |\|\ sawtooth to modulate the frequency of a
* voltage controlled triangle wave oscillator. *
*
******************************************************************************/
DISCRETE_OP_AMP_OSCILLATOR(NODE_60, 1, &polaris_boat_mod_info)
DISCRETE_OP_AMP_VCO1(POLARIS_SHIPSND, POLARIS_SX2_EN, NODE_60, &polaris_boat_vco_info)
/******************************************************************************
*
* Explosion - SX3 (When player, boat or boss plane is hit)
*
* When Enabled it makes a low frequency noise. As soon as it disables, it's
* volume starts decaying based on the RC values of 680k and 0.33uF. The
* final output is RC filtered.
*
* Note that when this is triggered, the sonar sound clock is disabled.
*
******************************************************************************/
DISCRETE_OP_AMP_TRIG_VCA(NODE_70, POLARIS_SX3_EN, 0, 0, POLARIS_NOISE_LO, 0, &polaris_exp_tvca_info)
DISCRETE_RCFILTER(NODE_71, 1, NODE_70, 560.0, CAP_U(.22))
DISCRETE_RCFILTER(POLARIS_EXPLOSIONSND, 1, NODE_71, RES_K(6.8), CAP_U(.22))
/******************************************************************************
*
* Plane Down - SX6
* Plane Up - SX7
*
* The oscillator is enabled when SX7 goes high. When SX6 is enabled the
* frequency lowers. When SX6 is disabled the frequency ramps back up.
* Also some NOISE_HI_FILT is mixed in so the frequency varies some.
*
******************************************************************************/
DISCRETE_INTEGRATE(NODE_80, POLARIS_SX6_EN, POLARIS_SX7_EN, &polaris_plane_integrate_info)
DISCRETE_OP_AMP_VCO2(POLARIS_PLANESND, POLARIS_SX7_EN, NODE_80, POLARIS_NOISE_HI_FILT, &polaris_plane_vco_info)
/******************************************************************************
*
* HIT - SX9 & SX10
*
* Following the schematic, 3 different sounds are produced.
* SX10 SX9 Effect
* 0 0 no sound
* 0 1 NOISE_HI_FILT while enabled
* 1 0 NOISE_LO_FILT while enabled (When a regular plane is hit)
* 1 1 NOISE_HI_FILT & NOISE_LO_FILT decaying imediately @ 680k, 0.22uF
*
******************************************************************************/
DISCRETE_OP_AMP_TRIG_VCA(POLARIS_HITSND, POLARIS_SX10_EN, POLARIS_SX9_EN, 0, POLARIS_NOISE_LO_FILT, POLARIS_NOISE_HI_FILT, &polaris_hit_tvca_info)
/******************************************************************************
*
* Final Mixing and Output
*
******************************************************************************/
DISCRETE_MIXER4(NODE_90, 1, POLARIS_SHOTSND, POLARIS_SONARSND, POLARIS_HITSND, POLARIS_PLANESND, &polaris_mixer_vr1_desc)
DISCRETE_MULTIPLY(NODE_91, 1, NODE_90, POLARIS_ADJ_VR1)
DISCRETE_MIXER2(NODE_92, 1, POLARIS_SHIPSND, POLARIS_SHIP_HITSND, &polaris_mixer_vr2_desc)
DISCRETE_MULTIPLY(NODE_93, 1, NODE_92, POLARIS_ADJ_VR2)
DISCRETE_MIXER4(NODE_94, POLARIS_SX5_EN, NODE_91, POLARIS_EXPLOSIONSND, NODE_93, POLARIS_MUSIC, &polaris_mixer_vr4_desc)
DISCRETE_OUTPUT(NODE_94, 1)
DISCRETE_SOUND_END
WRITE8_HANDLER( polaris_sh_port_1_w )
{
discrete_sound_w(POLARIS_MUSIC_DATA, data);
}
WRITE8_HANDLER( polaris_sh_port_2_w )
{
/* 0x01 - SX0 - Shot */
discrete_sound_w(POLARIS_SX0_EN, data & 0x01);
/* 0x02 - SX1 - Ship Hit (Sub) */
discrete_sound_w(POLARIS_SX1_EN, data & 0x02);
/* 0x04 - SX2 - Ship */
discrete_sound_w(POLARIS_SX2_EN, data & 0x04);
/* 0x08 - SX3 - Explosion */
discrete_sound_w(POLARIS_SX3_EN, data & 0x08);
/* 0x10 - SX4 */
/* 0x20 - SX5 - Sound Enable */
discrete_sound_w(POLARIS_SX5_EN, data & 0x20);
}
WRITE8_HANDLER( polaris_sh_port_3_w )
{
coin_lockout_global_w(data & 0x04); /* SX8 */
c8080bw_flip_screen_w(data & 0x20); /* SX11 */
/* 0x01 - SX6 - Plane Down */
discrete_sound_w(POLARIS_SX6_EN, data & 0x01);
/* 0x02 - SX7 - Plane Up */
discrete_sound_w(POLARIS_SX7_EN, data & 0x02);
/* 0x08 - SX9 - Hit */
discrete_sound_w(POLARIS_SX9_EN, data & 0x08);
/* 0x10 - SX10 - Hit */
discrete_sound_w(POLARIS_SX10_EN, data & 0x10);
}
/*******************************************************/
/* */
/* Taito "Space Chaser" */
/* */
/* The SN76477 still needs to be routed to the */
/* discrete system for filtering. */
/*******************************************************/
/*
* The dot sound is a square wave clocked by either the
* the 8V or 4V signals
*
* The frequencies are (for the 8V signal):
*
* 19.968 MHz crystal / 2 (Qa of 74160 #10) -> 9.984MHz
* / 2 (7474 #14) -> 4.992MHz
* / 256+16 (74161 #5 and #8) -> 18352.94Hz
* / 8 (8V) -> 2294.12 Hz
* / 2 the final freq. is 2 toggles -> 1147.06Hz
*
* for 4V, it's double at 2294.12Hz
*/
#define SCHASER_HSYNC 18352.94
#define SCHASER_4V SCHASER_HSYNC /2 /4
#define SCHASER_8V SCHASER_HSYNC /2 /8
struct SN76477interface schaser_sn76477_interface =
{
RES_K( 47), /* 4 noise_res */
RES_K(330), /* 5 filter_res */
CAP_P(470), /* 6 filter_cap */
RES_M(2.2), /* 7 decay_res */
CAP_U(1.0), /* 8 attack_decay_cap */
RES_K(4.7), /* 10 attack_res */
0, /* 11 amplitude_res (variable) */
RES_K(33), /* 12 feedback_res */
0, /* 16 vco_voltage */
CAP_U(0.1), /* 17 vco_cap */
RES_K(39), /* 18 vco_res */
5.0, /* 19 pitch_voltage */
RES_K(120), /* 20 slf_res */
CAP_U(1.0), /* 21 slf_cap */
CAP_U(0.1), /* 23 oneshot_cap */
RES_K(220), /* 24 oneshot_res */
1, /* 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 (variable) */
};
/* Nodes - Inputs */
#define SCHASER_DOT_EN NODE_01
#define SCHASER_DOT_SEL NODE_02
#define SCHASER_EXP_STREAM NODE_03
#define SCHASER_MUSIC_BIT NODE_04
#define SCHASER_SND_EN NODE_05
/* Nodes - Adjusters */
#define SCHASER_VR1 NODE_07
#define SCHASER_VR2 NODE_08
#define SCHASER_VR3 NODE_09
/* Nodes - Sounds */
#define SCHASER_DOT_SND NODE_10
#define SCHASER_EXP_SND NODE_11
#define SCHASER_MUSIC_SND NODE_12
DISCRETE_SOUND_START(schaser)
/************************************************/
/* Input register mapping for schaser */
/************************************************/
DISCRETE_INPUT_LOGIC (SCHASER_DOT_EN)
DISCRETE_INPUT_LOGIC (SCHASER_DOT_SEL)
// Change the constant to the stream input when working.
DISCRETE_CONSTANT(SCHASER_EXP_STREAM, 0)
// DISCRETE_INPUTX_STREAM(SCHASER_EXP_STREAM, 5.0/36764, 0)
DISCRETE_INPUTX_LOGIC (SCHASER_MUSIC_BIT, DEFAULT_TTL_V_LOGIC_1, 0, 0.0)
DISCRETE_INPUT_LOGIC (SCHASER_SND_EN)
/************************************************/
/* Volume adjusters. */
/* We will set them to adjust the realitive */
/* gains. */
/************************************************/
DISCRETE_ADJUSTMENT_TAG(SCHASER_VR1, 1, 0, RES_K(50)/(RES_K(50) + RES_K(470)), DISC_LINADJ, "VR1")
DISCRETE_ADJUSTMENT_TAG(SCHASER_VR2, 1, 0, RES_K(50)/(RES_K(50) + 560 + RES_K(6.8) + RES_K(2)), DISC_LINADJ, "VR2")
DISCRETE_ADJUSTMENT_TAG(SCHASER_VR3, 1, 0, RES_K(50)/(RES_K(50) + 560 + RES_K(6.8) + RES_K(10)), DISC_LINADJ, "VR3")
/************************************************/
/* Dot selection just selects between 4V and 8V */
/************************************************/
DISCRETE_SQUAREWFIX(NODE_20, 1, SCHASER_4V, DEFAULT_TTL_V_LOGIC_1, 50, 0, 0)
DISCRETE_SQUAREWFIX(NODE_21, 1, SCHASER_8V, DEFAULT_TTL_V_LOGIC_1, 50, 0, 0)
DISCRETE_SWITCH(NODE_22, SCHASER_DOT_EN, SCHASER_DOT_SEL, NODE_20, NODE_21)
DISCRETE_RCFILTER(NODE_23, 1, NODE_22, 560, CAP_U(.1))
DISCRETE_RCFILTER(NODE_24, 1, NODE_23, RES_K(6.8) + 560, CAP_U(.1))
DISCRETE_MULTIPLY(SCHASER_DOT_SND, 1, NODE_24, SCHASER_VR3)
/************************************************/
/* Explosion/Effect filtering */
/************************************************/
DISCRETE_RCFILTER(NODE_30, 1, SCHASER_EXP_STREAM, 560, CAP_U(.1))
DISCRETE_RCFILTER(NODE_31, 1, NODE_30, RES_K(6.8) + 560, CAP_U(.1))
DISCRETE_CRFILTER(NODE_32, 1, NODE_31, RES_K(6.8) + 560 + RES_K(2) + RES_K(50), CAP_U(1))
DISCRETE_MULTIPLY(SCHASER_EXP_SND, 1, NODE_32, SCHASER_VR2)
/************************************************/
/* Music is just a 1 bit DAC */
/************************************************/
DISCRETE_CRFILTER(NODE_40, 1, SCHASER_MUSIC_BIT, RES_K(470) + RES_K(50), CAP_U(.01))
DISCRETE_MULTIPLY(SCHASER_MUSIC_SND, 1, NODE_40, SCHASER_VR1)
/************************************************/
/* Final mix with gain */
/************************************************/
DISCRETE_ADDER3(NODE_90, SCHASER_SND_EN, SCHASER_DOT_SND, SCHASER_EXP_SND, SCHASER_MUSIC_SND)
DISCRETE_OUTPUT(NODE_90, 60000)
DISCRETE_SOUND_END
static const double schaser_effect_rc[8] =
{
0,
(RES_K(82) + RES_K(20)) * CAP_U(1),
(RES_K(39) + RES_K(20)) * CAP_U(1),
(1.0/ (1.0/RES_K(82) + 1.0/RES_K(39)) + RES_K(20)) * CAP_U(1),
(RES_K(15) + RES_K(20)) * CAP_U(1),
(1.0/ (1.0/RES_K(82) + 1.0/RES_K(15)) + RES_K(20)) * CAP_U(1),
(1.0/ (1.0/RES_K(39) + 1.0/RES_K(15)) + RES_K(20)) * CAP_U(1),
(1.0/ (1.0/RES_K(82) + 1.0/RES_K(39) + 1.0/RES_K(15)) + RES_K(20)) * CAP_U(1)
};
WRITE8_HANDLER( schaser_sh_port_1_w )
{
static int last_effect = 0;
int effect;
/* bit 0 - Dot Sound Enable (SX0)
bit 1 - Dot Sound Pitch (SX1)
bit 2 - Effect Sound A (SX2)
bit 3 - Effect Sound B (SX3)
bit 4 - Effect Sound C (SX4)
bit 5 - Explosion (SX5) */
discrete_sound_w(SCHASER_DOT_EN, data & 0x01);
discrete_sound_w(SCHASER_DOT_SEL, data & 0x02);
/* The effect is a variable rate 555 timer. A diode/resistor array is used to
* select the frequency. Because of the diode voltage drop, we can not use the
* standard 555 time formulas. Also, when effect=0, the charge resistor
* is disconnected. This causes the charge on the cap to slowly bleed off, but
* but the bleed time is so long, that we can just cheat and put the time on hold
* when effect = 0. */
effect = (data >> 2) & 0x07;
if (last_effect != effect)
{
if (effect)
{
if (attotime_compare(schaser_effect_555_time_remain, attotime_zero) != 0)
{
/* timer re-enabled, use up remaining 555 high time */
timer_adjust(schaser_effect_555_timer, schaser_effect_555_time_remain, effect, attotime_zero);
}
else if (!schaser_effect_555_is_low)
{
/* set 555 high time */
attotime new_time = attotime_make(0, ATTOSECONDS_PER_SECOND * .8873 * schaser_effect_rc[effect]);
timer_adjust(schaser_effect_555_timer, new_time, effect, attotime_zero);
}
}
else
{
/* disable effect - stops at end of low cycle */
if (!schaser_effect_555_is_low)
{
schaser_effect_555_time_remain = timer_timeleft(schaser_effect_555_timer);
timer_adjust(schaser_effect_555_timer, attotime_never, 0, attotime_never);
}
}
last_effect = effect;
}
schaser_explosion = (data >> 5) & 0x01;
if (schaser_explosion)
{
SN76477_amplitude_res_w(0, 1.0 / (1.0/RES_K(200) + 1.0/RES_K(68)));
}
else
{
SN76477_amplitude_res_w(0, RES_K(200));
}
SN76477_enable_w(0, !(schaser_effect_555_is_low || schaser_explosion));
SN76477_one_shot_cap_voltage_w(0, !(schaser_effect_555_is_low || schaser_explosion) ? 0 : SN76477_EXTERNAL_VOLTAGE_DISCONNECT);
SN76477_mixer_b_w(0, schaser_explosion);
}
WRITE8_HANDLER( schaser_sh_port_2_w )
{
/* bit 0 - Music (DAC) (SX6)
bit 1 - Sound Enable (SX7)
bit 2 - Coin Lockout (SX8)
bit 3 - Field Control A (SX9)
bit 4 - Field Control B (SX10)
bit 5 - Flip Screen */
discrete_sound_w(SCHASER_MUSIC_BIT, data & 0x01);
discrete_sound_w(SCHASER_SND_EN, data & 0x02);
sound_global_enable(data & 0x02);
coin_lockout_global_w(data & 0x04);
schaser_background_control_w(data & 0x18);
c8080bw_flip_screen_w(data & 0x20);
}
static TIMER_CALLBACK( schaser_effect_555_cb )
{
int effect = param;
attotime new_time;
/* Toggle 555 output */
schaser_effect_555_is_low = !schaser_effect_555_is_low;
schaser_effect_555_time_remain = attotime_zero;
if (schaser_effect_555_is_low)
new_time = attotime_div(PERIOD_OF_555_ASTABLE(0, RES_K(20), CAP_U(1)), 2);
else
{
if (effect)
new_time = attotime_make(0, ATTOSECONDS_PER_SECOND * .8873 * schaser_effect_rc[effect]);
else
new_time = attotime_never;
}
timer_adjust(schaser_effect_555_timer, new_time, effect, attotime_zero);
SN76477_enable_w(0, !(schaser_effect_555_is_low || schaser_explosion));
SN76477_one_shot_cap_voltage_w(0, !(schaser_effect_555_is_low || schaser_explosion) ? 0 : SN76477_EXTERNAL_VOLTAGE_DISCONNECT);
}
MACHINE_START( schaser )
{
schaser_effect_555_timer = timer_alloc(schaser_effect_555_cb);
machine_start_mw8080bw(machine);
}
MACHINE_RESET( schaser )
{
schaser_effect_555_is_low = 0;
timer_adjust(schaser_effect_555_timer, attotime_never, 0, attotime_never);
schaser_sh_port_1_w(0, 0);
schaser_sh_port_2_w(0, 0);
schaser_effect_555_time_remain = attotime_zero;
machine_reset_mw8080bw(machine);
}
/****************************************************/
/* Rolling Crash / Moon Base */
/* - Moon Base uses same ports and bits as invaders */
/* - Press Left or Right to choose game to play */
/****************************************************/
WRITE8_HANDLER( rollingc_sh_port_w )
{
UINT8 rising_bits = data & ~port_3_last;
if (rising_bits & 0x02) sample_start(4, 0, 0); /* Steering */
if (rising_bits & 0x04) sample_start(0, 1, 0); /* Collision */
if (rising_bits & 0x10) sample_start(1, 8, 0); /* Computer car is starting to move */
port_3_last = data;
}
/*************************************************************************************/
/* Invader's Revenge preliminary sound */
/* Correct samples not available */
/* Notes: */
/* Init sequence: 0x01 (20 times), 0x40 (20 times), 0x4c, 0x40, 0x44, 0x40 (9 times).*/
/* Player 1 start sequence: 0x0c, 0x20, 0x22. */
/* Start of Attract mode: 0x04. */
/* Unknown codes: 0x28, 0x2a, 0x0c, 0x34, 0x2c, 0x2e, 0x1c. */
/*************************************************************************************/
WRITE8_HANDLER( invrvnge_sh_port_w )
{
switch (data)
{
case 0x06:
sample_start(1, 0, 0); /* Shoot */
break;
case 0x14:
sample_start(2, 2, 0); /* Hit Alien */
break;
case 0x16:
sample_start(2, 5, 0); /* Hit Asteroid */
break;
case 0x1e:
sample_start(3, 1, 0); /* Death (followed by 0x0a byte), also bit 4 of port 5 */
break;
case 0x18: /* Fuel Low */
case 0x30: /* Fuel bar filling up */
sample_start(4, 7, 0);
break;
case 0x02: /* Coin */
case 0x24: /* Alien dropping to steal fuel */
case 0x26: /* Alien lifting with fuel */
case 0x32: /* UFO drops a bomb */
break;
case 0x3a: /* Thrust, Docking, extra ship? */
sample_start(0, 8, 0);
break;
}
}
/*****************************************/
/* Lupin III preliminary sound */
/* Correct samples not available */
/*****************************************/
WRITE8_HANDLER( lupin3_sh_port_1_w )
{
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(0, 6, 0); /* Walking, get money */
SN76477_enable_w(0, data & 0x02 ? 0:1); /* Helicopter */
if (rising_bits & 0x04) sample_start(0, 7, 0); /* Translocate */
if (rising_bits & 0x08) sample_start(0, 1, 0); /* Jail */
if (rising_bits & 0x10) sample_start(3, 8, 0); /* Bonus Man */
port_1_last = data;
}
WRITE8_HANDLER( lupin3_sh_port_2_w )
{
UINT8 rising_bits = data & ~port_2_last;
if (rising_bits & 0x01) sample_start(0, 3, 0); /* Lands on top of building, wife kicks man */
if (rising_bits & 0x02) sample_start(1, 2, 0); /* deposit money, start intermission, end game */
if (rising_bits & 0x04) sample_start(2, 5, 0); /* deposit money, start intermission, Slides down rope */
if (rising_bits & 0x08) sample_start(3, 0, 0); /* start intermission, end game */
//if (rising_bits & 0x10) sample_start(3, 9, 0); /* Dog barking */
c8080bw_flip_screen_w(data & 0x20);
port_2_last = data;
}
/*****************************************/
/* Space Chaser (CV) preliminary sound */
/* Much more work needs to be done */
/*****************************************/
WRITE8_HANDLER( schasrcv_sh_port_1_w )
{
/* bit 2 = 2nd speedup
bit 3 = 1st speedup
Death is a stream of ff's with some fe's thrown in */
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x02) sample_start(1, 6, 0); /* Ran over a dot */
if (rising_bits & 0x10) sample_start(0, 1, 0); /* Death */
port_1_last = data;
}
WRITE8_HANDLER( schasrcv_sh_port_2_w )
{
speaker_level_w(0, (data & 0x01) ? 1 : 0); /* End-of-Level */
sound_global_enable(data & 0x10);
c8080bw_flip_screen_w(data & 0x20);
}
/*******************************************************************/
/* Yosakdon preliminary sound */
/* No information available as what the correct sounds are */
/*******************************************************************/
WRITE8_HANDLER( yosakdon_sh_port_1_w )
{
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(0, 3, 0); /* Game Over */
if (rising_bits & 0x02) sample_start(2, 0, 0); /* Bird dead */
if (rising_bits & 0x04) sample_start(0, 1, 0); /* Rifle being fired */
if (rising_bits & 0x08) sample_start(1, 2, 0); /* Man dead */
if (rising_bits & 0x10) sample_start(5, 8, 0); /* Bonus Man? */
sound_global_enable(data & 0x20);
port_1_last = data;
}
WRITE8_HANDLER( yosakdon_sh_port_2_w )
{
UINT8 rising_bits = data & ~port_2_last;
if (rising_bits & 0x01) sample_start(1, 6, 0); /* Ready? , Game Over */
if (rising_bits & 0x04) sample_start(3, 7, 0); /* Big bird dead */
SN76477_enable_w(0, data & 0x08 ? 0:1); /* Big bird */
if (rising_bits & 0x10) sample_start(2, 7, 0); /* Game Over */
c8080bw_flip_screen_w(data & 0x20);
port_2_last = data;
}
/*****************************************/
/* shuttlei preliminary sound */
/* Proper samples are unavailable */
/*****************************************/
WRITE8_HANDLER( shuttlei_sh_port_1_w )
{
/* bit 3 is high while you are alive and playing */
UINT8 rising_bits = data & ~port_1_last;
if (rising_bits & 0x01) sample_start(4, 4, 0); /* Fleet move */
if (rising_bits & 0x02) sample_start(5, 8, 0); /* Extra Tank */
SN76477_enable_w(0, data & 0x04 ? 0:1); /* UFO */
port_1_last = data;
}
WRITE8_HANDLER( shuttlei_sh_port_2_w )
{
switch (data)
{
case 0x23:
sample_start(2, 2, 0); /* Hit */
break;
case 0x2b:
sample_start(0, 0, 0); /* Shoot */
break;
case 0xa3:
sample_start(3, 7, 0); /* Hit UFO */
break;
case 0xab:
sample_start(1, 1, 0); /* Death */
break;
}
}