diff options
Diffstat (limited to 'trunk/src/mame/audio/bsktball.c')
-rw-r--r-- | trunk/src/mame/audio/bsktball.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/trunk/src/mame/audio/bsktball.c b/trunk/src/mame/audio/bsktball.c new file mode 100644 index 00000000000..382f35ebeef --- /dev/null +++ b/trunk/src/mame/audio/bsktball.c @@ -0,0 +1,135 @@ +/************************************************************************* + + audio\bsktball.c + +*************************************************************************/ +#include "emu.h" +#include "includes/bsktball.h" +#include "sound/discrete.h" + +/*************************************************************************** +Sound handlers +***************************************************************************/ +WRITE8_DEVICE_HANDLER( bsktball_bounce_w ) +{ + discrete_sound_w(device, BSKTBALL_CROWD_DATA, data & 0x0f); // Crowd + discrete_sound_w(device, BSKTBALL_BOUNCE_EN, data & 0x10); // Bounce +} + +WRITE8_DEVICE_HANDLER( bsktball_note_w ) +{ + discrete_sound_w(device, BSKTBALL_NOTE_DATA, data); // Note +} + +WRITE8_DEVICE_HANDLER( bsktball_noise_reset_w ) +{ + discrete_sound_w(device, BSKTBALL_NOISE_EN, offset & 0x01); +} + + +/************************************************************************/ +/* bsktball Sound System Analog emulation */ +/************************************************************************/ + +static const discrete_lfsr_desc bsktball_lfsr = +{ + DISC_CLK_IS_FREQ, + 16, /* Bit Length */ + 0, /* Reset Value */ + 0, /* Use Bit 0 as XOR input 0 */ + 14, /* Use Bit 14 as XOR input 1 */ + DISC_LFSR_XNOR, /* Feedback stage1 is XNOR */ + 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 already inverted by XNOR */ + 15 /* Output bit */ +}; + +static const discrete_dac_r1_ladder bsktball_crowd_r1_ladder = +{ + 4, + {RES_K(390), RES_K(220), RES_K(100), RES_K(56)}, // r55, r54, r53, r52 + 0, 0, // no bias + RES_K(1), // r21 + CAP_U(0.1) // c32 +}; + +static const discrete_op_amp_filt_info bsktball_crowd_filt = +{ + 1.0/(1.0/RES_K(390) + 1.0/RES_K(220) + 1.0/RES_K(100) + 1.0/RES_K(56) + 1.0/RES_K(1)), // r55, r54, r53, r52, r21 + 0, 0, 0, + RES_K(330), // r58 + CAP_U(.01), // c55 + CAP_U(.022), // c56 + 0, + 5, 12, 0 +}; + +static const discrete_mixer_desc bsktball_mixer = +{ + DISC_MIXER_IS_OP_AMP, + {RES_K(47), RES_K(47), RES_K(220)}, // r56, r57, r60 + {0}, // no rNodes + {CAP_U(.01), CAP_U(.01), CAP_U(.01)}, // c53, c54, c57 + 0, + RES_K(47), // r61 + CAP_U(.001), // c58 + CAP_U(1), + 5, + 7500 +}; + +#define BSKTBALL_32H 12096000.0/4/32 +#define BSKTBALL_256H 12096000.0/768 + +/* Nodes - Sounds */ +#define BSKTBALL_NOISE NODE_10 +#define BSKTBALL_BOUNCE_SND BSKTBALL_BOUNCE_EN +#define BSKTBALL_NOTE_SND NODE_12 +#define BSKTBALL_CROWD_SND NODE_13 + +DISCRETE_SOUND_START(bsktball) + /************************************************/ + /* Input register mapping for bsktball */ + /************************************************/ + /* NODE GAIN OFFSET INIT */ + DISCRETE_INPUT_DATA (BSKTBALL_NOTE_DATA) + DISCRETE_INPUT_DATA (BSKTBALL_CROWD_DATA) + /* Bounce is a trigger fed directly to the amp */ + DISCRETE_INPUTX_LOGIC(BSKTBALL_BOUNCE_EN, DEFAULT_TTL_V_LOGIC_1, 0, 0.0) + DISCRETE_INPUT_NOT (BSKTBALL_NOISE_EN) + + /************************************************/ + /* Crowd effect is variable amplitude, filtered */ + /* random noise. */ + /* LFSR clk = 256H = 15750.0Hz */ + /************************************************/ + DISCRETE_LFSR_NOISE(BSKTBALL_NOISE, BSKTBALL_NOISE_EN, BSKTBALL_NOISE_EN, BSKTBALL_256H, 1, 0, .5, &bsktball_lfsr) + DISCRETE_SWITCH(NODE_20, 1, BSKTBALL_NOISE, 0, BSKTBALL_CROWD_DATA) // enable data, gate D11 + DISCRETE_DAC_R1(NODE_21, NODE_20, DEFAULT_TTL_V_LOGIC_1, &bsktball_crowd_r1_ladder) + DISCRETE_OP_AMP_FILTER(BSKTBALL_CROWD_SND, 1, NODE_21, 0, DISC_OP_AMP_FILTER_IS_BAND_PASS_1M, &bsktball_crowd_filt) + + /************************************************/ + /* Note sound is created by a divider circuit. */ + /* The master clock is the 32H signal, which is */ + /* 12.096MHz/128. This is then sent to a */ + /* preloadable 8 bit counter, which loads the */ + /* value from OUT30 when overflowing from 0xFF */ + /* to 0x00. Therefore it divides by 2 (OUT30 */ + /* = FE) to 256 (OUT30 = 00). */ + /* There is also a final /2 stage. */ + /* Note that there is no music disable line. */ + /* When there is no music, the game sets the */ + /* oscillator to 0Hz. (OUT30 = FF) */ + /************************************************/ + DISCRETE_NOTE(NODE_30, 1, BSKTBALL_32H, BSKTBALL_NOTE_DATA, 255, 1, DISC_CLK_IS_FREQ | DISC_OUT_IS_ENERGY) + DISCRETE_GAIN(BSKTBALL_NOTE_SND, NODE_30, DEFAULT_TTL_V_LOGIC_1) + + + /************************************************/ + /* Mixing stage - B11 */ + /************************************************/ + DISCRETE_MIXER3(NODE_90, 1, BSKTBALL_NOTE_SND, BSKTBALL_BOUNCE_SND, BSKTBALL_CROWD_SND, &bsktball_mixer) + DISCRETE_OUTPUT(NODE_90, 1) +DISCRETE_SOUND_END |