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-rw-r--r--trunk/src/mame/audio/nitedrvr.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/trunk/src/mame/audio/nitedrvr.c b/trunk/src/mame/audio/nitedrvr.c
new file mode 100644
index 00000000000..7537b2cb9bd
--- /dev/null
+++ b/trunk/src/mame/audio/nitedrvr.c
@@ -0,0 +1,146 @@
+/*************************************************************************
+
+ audio\nitedrvr.c
+
+*************************************************************************/
+#include "emu.h"
+#include "includes/nitedrvr.h"
+#include "sound/discrete.h"
+
+
+/* Discrete Sound Emulation */
+
+static const discrete_lfsr_desc nitedrvr_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 NITEDRVR_NOISE NODE_10
+#define NITEDRVR_BANG_SND NODE_11
+#define NITEDRVR_MOTOR_SND NODE_12
+#define NITEDRVR_SCREECH1_SND NODE_13
+#define NITEDRVR_SCREECH2_SND NODE_14
+
+DISCRETE_SOUND_START(nitedrvr)
+ /************************************************/
+ /* nitedrvr Effects Relataive Gain Table */
+ /* */
+ /* Effect V-ampIn Gain ratio Relative */
+ /* Bang 3.8 5/(5+6.8) 1000.0 */
+ /* Motor 3.8 5/(5+10) 786.7 */
+ /* Screech1 3.8 5/(5+47) 226.9 */
+ /* Screech2 3.8 5/(5+47) 226.9 */
+ /************************************************/
+
+ /************************************************/
+ /* Input register mapping for nitedrvr */
+ /************************************************/
+ /* NODE GAIN OFFSET INIT */
+ DISCRETE_INPUTX_DATA (NITEDRVR_BANG_DATA, 1000.0/15, 0.0, 0.0)
+ DISCRETE_INPUT_LOGIC (NITEDRVR_SKID1_EN)
+ DISCRETE_INPUT_LOGIC (NITEDRVR_SKID2_EN)
+ DISCRETE_INPUTX_DATA (NITEDRVR_MOTOR_DATA, -1, 0x0f, 0)
+ DISCRETE_INPUT_LOGIC (NITEDRVR_CRASH_EN)
+ DISCRETE_INPUT_NOT (NITEDRVR_ATTRACT_EN)
+
+ /************************************************/
+ /* NOTE: Motor circuit is a rip from Sprint for */
+ /* now. This will have to be converted to 566. */
+ /* */
+ /* 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 */
+ /************************************************/
+ DISCRETE_RCFILTER(NODE_20, NITEDRVR_MOTOR_DATA, 123037, 2.2e-6)
+ DISCRETE_ADJUSTMENT(NODE_21, (214.0-27.0)/12/31, (4416.0-27.0)/12/31, DISC_LOGADJ, "MOTOR")
+ DISCRETE_MULTIPLY(NODE_22, NODE_20, NODE_21)
+
+ DISCRETE_MULTADD(NODE_23, NODE_22, 2, 27.0/6) /* F1 = /12*2 = /6 */
+ DISCRETE_SQUAREWAVE(NODE_24, 1, NODE_23, (786.7/3), 50.0, 0, 0)
+ DISCRETE_RCFILTER(NODE_25, NODE_24, 10000, 1e-7)
+
+ DISCRETE_MULTADD(NODE_26, NODE_22, 3, 27.0/4) /* F2 = /12*3 = /4 */
+ DISCRETE_SQUAREWAVE(NODE_27, 1, NODE_26, (786.7/3), 50.0, 0, 0)
+ DISCRETE_RCFILTER(NODE_28, NODE_27, 10000, 1e-7)
+
+ DISCRETE_MULTADD(NODE_29, NODE_22, 4, 27.0/3) /* F3 = /12*4 = /3 */
+ DISCRETE_SQUAREWAVE(NODE_30, 1, NODE_29, (786.7/3), 100.0/3, 0, 360.0/3)
+ DISCRETE_RCFILTER(NODE_31, NODE_30, 10000, 1e-7)
+
+ DISCRETE_ADDER3(NITEDRVR_MOTOR_SND, NITEDRVR_ATTRACT_EN, NODE_25, NODE_28, NODE_31)
+
+ /************************************************/
+ /* Bang circuit is built around a noise */
+ /* generator built from 2 shift registers that */
+ /* are clocked by the 4V signal. */
+ /* 4V = HSYNC/2/4 */
+ /* = 15750/2/4 */
+ /* Output is integrated to apply decay. */
+ /************************************************/
+ DISCRETE_LFSR_NOISE(NITEDRVR_NOISE, NITEDRVR_CRASH_EN, NITEDRVR_CRASH_EN, 15750.0/2/4, 1.0, 0, 0, &nitedrvr_lfsr)
+
+ DISCRETE_MULTIPLY(NODE_62, NITEDRVR_NOISE, NITEDRVR_BANG_DATA)
+ DISCRETE_RCFILTER(NITEDRVR_BANG_SND, NODE_62, 545.6, 3.3e-7)
+
+ /************************************************/
+ /* Skid circuits ripped from other drivers */
+ /* for now. */
+ /* */
+ /* 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, NITEDRVR_NOISE)
+ DISCRETE_RCFILTER(NODE_71, NODE_70, 1000, 1e-5)
+ DISCRETE_MULTADD(NODE_72, NODE_71, 940.0-630.0, ((940.0-630.0)/2)+630.0)
+ DISCRETE_SQUAREWAVE(NITEDRVR_SCREECH1_SND, NITEDRVR_SKID1_EN, NODE_72, 226.9, 31.5, 0, 0.0)
+
+ DISCRETE_MULTADD(NODE_75, NODE_71, 1380.0-626.0, 626.0+((1380.0-626.0)/2)) /* Frequency */
+ DISCRETE_MULTADD(NODE_76, NODE_71, 32.0-13.0, 13.0+((32.0-13.0)/2)) /* Duty */
+ DISCRETE_SQUAREWAVE(NITEDRVR_SCREECH2_SND, NITEDRVR_SKID2_EN, NODE_75, 226.9, NODE_76, 0, 0.0)
+
+ /************************************************/
+ /* Combine all sound sources. */
+ /* Add some final gain to get to a good sound */
+ /* level. */
+ /************************************************/
+ DISCRETE_ADDER4(NODE_90, 1, NITEDRVR_MOTOR_SND, NITEDRVR_BANG_SND, NITEDRVR_SCREECH1_SND, NITEDRVR_SCREECH2_SND)
+
+ DISCRETE_OUTPUT(NODE_90, 65534.0/(786.7+1000.0+226.9))
+DISCRETE_SOUND_END