diff options
Diffstat (limited to 'src/mame/audio/dragrace.c')
-rw-r--r-- | src/mame/audio/dragrace.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/src/mame/audio/dragrace.c b/src/mame/audio/dragrace.c new file mode 100644 index 00000000000..766153f0050 --- /dev/null +++ b/src/mame/audio/dragrace.c @@ -0,0 +1,191 @@ +/************************************************************************* + + audio\dragrace.c + +*************************************************************************/ +#include "driver.h" +#include "dragrace.h" +#include "sound/discrete.h" + +/************************************************************************/ +/* dragrace Sound System Analog emulation */ +/************************************************************************/ + +static const discrete_lfsr_desc dragrace_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 */ +}; + +/* Nodes - Sounds */ +#define DRAGRACE_NOISE NODE_10 +#define DRAGRACE_SCREECH1_SND NODE_11 +#define DRAGRACE_SCREECH2_SND NODE_12 +#define DRAGRACE_LOTONE_SND NODE_13 +#define DRAGRACE_HITONE_SND NODE_14 +#define DRAGRACE_TONE_SND NODE_15 +#define DRAGRACE_EXPLODE1_SND NODE_16 +#define DRAGRACE_EXPLODE2_SND NODE_17 +#define DRAGRACE_MOTOR1_SND NODE_18 +#define DRAGRACE_MOTOR2_SND NODE_19 + +DISCRETE_SOUND_START(dragrace) + /************************************************/ + /* dragrace Effects Relataive Gain Table */ + /* */ + /* Effect V-ampIn Gain ratio Relative */ + /* LoTone 3.8 10/32 593.8 */ + /* HiTone 3.8 10/32 593.8 */ + /* Screech 3.8 10/330 57.6 */ + /* Motor 3.8 10/32.67 581.6 */ + /* Explode 5.0 10/25 1000.0 */ + /************************************************/ + + + /************************************************/ + /* Input register mapping for dragrace */ + /************************************************/ + DISCRETE_INPUT_LOGIC(DRAGRACE_SCREECH1_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_SCREECH2_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_LOTONE_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_HITONE_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_EXPLODE1_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_EXPLODE2_EN) + DISCRETE_INPUT_DATA (DRAGRACE_MOTOR1_DATA) + DISCRETE_INPUT_DATA (DRAGRACE_MOTOR2_DATA) + DISCRETE_INPUT_LOGIC(DRAGRACE_MOTOR1_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_MOTOR2_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_KLEXPL1_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_KLEXPL2_EN) + DISCRETE_INPUT_LOGIC(DRAGRACE_ATTRACT_EN) + + /************************************************/ + /* Motor sound circuit is based on a 556 VCO */ + /* with the input frequency set by the MotorSND */ + /* latch (4 bit). This freqency is then used to */ + /* driver a modulo 12 counter, with div6, 4 & 3 */ + /* summed as the output of the circuit. */ + /* VCO Output is Sq wave = 27-382Hz */ + /* F1 freq - (Div6) */ + /* F2 freq = (Div4) */ + /* F3 freq = (Div3) 33.3% duty, 33.3 deg phase */ + /* To generate the frequency we take the freq. */ + /* diff. and /15 to get all the steps between */ + /* 0 - 15. Then add the low frequency and send */ + /* that value to a squarewave generator. */ + /* Also as the frequency changes, it ramps due */ + /* to a 2.2uf capacitor on the R-ladder. */ + /* Note the VCO freq. is controlled by a 250k */ + /* pot. The freq. used here is for the pot set */ + /* to 125k. The low freq is allways the same. */ + /* This adjusts the high end. */ + /* 0k = 214Hz. 250k = 4416Hz */ + /* NOTE: freqs are ripped from Sprint for now. */ + /************************************************/ + DISCRETE_RCFILTER(NODE_20, 1, DRAGRACE_MOTOR1_DATA, 119898, 2.2e-6) + DISCRETE_ADJUSTMENT_TAG(NODE_21, 1, (214.0-27.0)/12/31, (4416.0-27.0)/12/31, DISC_LOGADJ, "MOTOR1") + DISCRETE_MULTIPLY(NODE_22, 1, NODE_20, NODE_21) + + DISCRETE_MULTADD(NODE_23, 1, NODE_22, 2, 27.0/6) /* F1 = /12*2 = /6 */ + DISCRETE_SQUAREWAVE(NODE_24, 1, NODE_23, (581.6/3), 50.0, 0, 0) + DISCRETE_RCFILTER(NODE_25, 1, NODE_24, 10000, 1e-7) + + DISCRETE_MULTADD(NODE_26, 1, NODE_22, 3, 27.0/4) /* F2 = /12*3 = /4 */ + DISCRETE_SQUAREWAVE(NODE_27, 1, NODE_26, (581.6/3), 50.0, 0, 0) + DISCRETE_RCFILTER(NODE_28, 1, NODE_27, 10000, 1e-7) + + DISCRETE_MULTADD(NODE_29, 1, NODE_22, 4, 27.0/3) /* F3 = /12*4 = /3 */ + DISCRETE_SQUAREWAVE(NODE_30, 1, NODE_29, (581.6/3), 100.0/3, 0, 360.0/3) + DISCRETE_RCFILTER(NODE_31, 1, NODE_30, 10000, 1e-7) + + DISCRETE_ADDER3(DRAGRACE_MOTOR1_SND, DRAGRACE_MOTOR1_EN, NODE_25, NODE_28, NODE_31) + + /************************************************/ + /* Car2 motor sound is basically the same as */ + /* Car1. But I shifted the frequencies up for */ + /* it to sound different from car1. */ + /************************************************/ + DISCRETE_RCFILTER(NODE_40, 1, DRAGRACE_MOTOR2_DATA, 119898, 2.2e-6) + DISCRETE_ADJUSTMENT_TAG(NODE_41, 1, (214.0-27.0)/12/31, (4416.0-27.0)/12/31, DISC_LOGADJ, "MOTOR2") + DISCRETE_MULTIPLY(NODE_42, 1, NODE_40, NODE_41) + + DISCRETE_MULTADD(NODE_43, 1, NODE_42, 2, 27.0/6) /* F1 = /12*2 = /6 */ + DISCRETE_SQUAREWAVE(NODE_44, 1, NODE_43, (581.6/3), 50.0, 0, 0) + DISCRETE_RCFILTER(NODE_45, 1, NODE_44, 10000, 1e-7) + + DISCRETE_MULTADD(NODE_46, 1, NODE_42, 3, 27.0/4) /* F2 = /12*3 = /4 */ + DISCRETE_SQUAREWAVE(NODE_47, 1, NODE_46, (581.6/3), 50.0, 0, 0) + DISCRETE_RCFILTER(NODE_48, 1, NODE_47, 10000, 1e-7) + + DISCRETE_MULTADD(NODE_49, 1, NODE_42, 4, 27.0/3) /* F3 = /12*4 = /3 */ + DISCRETE_SQUAREWAVE(NODE_50, 1, NODE_49, (581.6/3), 100.0/3, 0, 360.0/3) + DISCRETE_RCFILTER(NODE_51, 1, NODE_50, 10000, 1e-7) + + DISCRETE_ADDER3(DRAGRACE_MOTOR2_SND, DRAGRACE_MOTOR2_EN, NODE_45, NODE_48, NODE_51) + + /************************************************/ + /* Explosion circuit is built around a noise */ + /* generator built from 2 shift registers that */ + /* are clocked by the 1V signal. */ + /* 1V = HSYNC/2 */ + /* = 15750/2 */ + /* Output is integrated to apply decay. */ + /************************************************/ + DISCRETE_LFSR_NOISE(DRAGRACE_NOISE, 1, DRAGRACE_ATTRACT_EN, 15750.0/2, 1.0, 0, 0, &dragrace_lfsr) + + DISCRETE_RAMP(NODE_61, DRAGRACE_EXPLODE1_EN, DRAGRACE_EXPLODE1_EN, (1000.0-0.0)/1, 1000.0, 0.0, 1000.0) + DISCRETE_MULTIPLY(NODE_62, 1, DRAGRACE_NOISE, NODE_61) + DISCRETE_RCFILTER(DRAGRACE_EXPLODE1_SND, DRAGRACE_KLEXPL1_EN, NODE_62, 1500, 2.2e-7) + + DISCRETE_RAMP(NODE_66, DRAGRACE_EXPLODE2_EN, DRAGRACE_EXPLODE2_EN, (1000.0-0.0)/1, 1000.0, 0.0, 1000.0) + DISCRETE_MULTIPLY(NODE_67, 1, DRAGRACE_NOISE, NODE_66) + DISCRETE_RCFILTER(DRAGRACE_EXPLODE2_SND, DRAGRACE_KLEXPL2_EN, NODE_67, 1500, 2.2e-7) + + /************************************************/ + /* Skid circuits takes the noise output from */ + /* the crash circuit and applies +ve feedback */ + /* to cause oscillation. There is also an RC */ + /* filter on the input to the feedback cct. */ + /* RC is 1K & 10uF */ + /* Feedback cct is modelled by using the RC out */ + /* as the frequency input on a VCO, */ + /* breadboarded freq range as: */ + /* 0 = 940Hz, 34% duty */ + /* 1 = 630Hz, 29% duty */ + /* the duty variance is so small we ignore it */ + /************************************************/ + DISCRETE_INVERT(NODE_70, DRAGRACE_NOISE) + DISCRETE_MULTADD(NODE_71, 1, NODE_70, 940.0-630.0, ((940.0-630.0)/2)+630.0) + DISCRETE_RCFILTER(NODE_72, 1, NODE_71, 1000, 1e-5) + DISCRETE_SQUAREWAVE(NODE_73, 1, NODE_72, 407.8, 31.5, 0, 0.0) + DISCRETE_ONOFF(DRAGRACE_SCREECH1_SND, DRAGRACE_SCREECH1_EN, NODE_73) + DISCRETE_ONOFF(DRAGRACE_SCREECH2_SND, DRAGRACE_SCREECH2_EN, NODE_73) + + /************************************************/ + /* LoTone = 32V = 15750Hz/2/32 */ + /* HiTone = 4V = 15750Hz/2/4 */ + /************************************************/ + DISCRETE_SQUAREWFIX(DRAGRACE_LOTONE_SND, DRAGRACE_LOTONE_EN, 15750.0/2/32, 593.8, 50.0, 0, 0.0) + DISCRETE_SQUAREWFIX(DRAGRACE_HITONE_SND, DRAGRACE_HITONE_EN, 15750.0/2/4, 593.8, 50.0, 0, 0.0) + DISCRETE_ADDER2(DRAGRACE_TONE_SND, 1, DRAGRACE_LOTONE_SND, DRAGRACE_HITONE_SND) + + /************************************************/ + /* Combine all 5 sound sources. */ + /* Add some final gain to get to a good sound */ + /* level. */ + /************************************************/ + DISCRETE_ADDER4(NODE_90, DRAGRACE_ATTRACT_EN, DRAGRACE_TONE_SND, DRAGRACE_MOTOR1_SND, DRAGRACE_EXPLODE1_SND, DRAGRACE_SCREECH1_SND) + DISCRETE_ADDER4(NODE_91, DRAGRACE_ATTRACT_EN, DRAGRACE_TONE_SND, DRAGRACE_MOTOR2_SND, DRAGRACE_EXPLODE2_SND, DRAGRACE_SCREECH2_SND) + + DISCRETE_OUTPUT(NODE_90, 65534.0/(593.8+581.6+1000.0+57.6)) + DISCRETE_OUTPUT(NODE_91, 65534.0/(593.8+581.6+1000.0+57.6)) +DISCRETE_SOUND_END |