[wrap]
/************************************************************************
*
* MAME - Discrete sound system emulation library
*
* Written by Keith Wilkins (mame@esplexo.co.uk)
*
* (c) K.Wilkins 2000
*
************************************************************************
*
* DSS_COUNTER - External clock Binary Counter
* DSS_LFSR_NOISE - Linear Feedback Shift Register Noise
* DSS_NOISE - Noise Source - Random source
* DSS_NOTE - Note/tone generator
* DSS_OP_AMP_OSC - Op Amp oscillator circuits
* DSS_SAWTOOTHWAVE - Sawtooth waveform generator
* DSS_SCHMITT_OSC - Schmitt Feedback Oscillator
* DSS_SINEWAVE - Sinewave generator source code
* DSS_SQUAREWAVE - Squarewave generator source code
* DSS_SQUAREWFIX - Squarewave generator - fixed frequency
* DSS_SQUAREWAVE2 - Squarewave generator - by t_on/t_off
* DSS_TRIANGLEWAVE - Triangle waveform generator
*
************************************************************************/
struct dss_adsr_context
{
double phase;
};
struct dss_counter_context
{
int clock_type;
int out_type;
int is_7492;
int last; /* Last clock state */
int count; /* current count */
double t_clock; /* fixed counter clock in seconds */
double t_left; /* time unused during last sample in seconds */
};
#define DSS_INV_TAB_SIZE 500
struct dss_inverter_osc_context
{
double w;
double wc;
double v_cap;
double v_g2_old;
double rp;
double r1;
double r2;
double c;
double tf_a;
double tf_b;
double tf_tab[DSS_INV_TAB_SIZE];
};
struct dss_lfsr_context
{
unsigned int lfsr_reg;
int last; /* Last clock state */
double t_clock; /* fixed counter clock in seconds */
double t_left; /* time unused during last sample in seconds */
double sample_step;
double t;
UINT8 reset_on_high;
UINT8 invert_output;
UINT8 out_is_f0;
};
struct dss_noise_context
{
double phase;
};
struct dss_note_context
{
int clock_type;
int out_type;
int last; /* Last clock state */
double t_clock; /* fixed counter clock in seconds */
double t_left; /* time unused during last sample in seconds */
int max1; /* Max 1 Count stored as int for easy use. */
int max2; /* Max 2 Count stored as int for easy use. */
int count1; /* current count1 */
int count2; /* current count2 */
};
struct dss_op_amp_osc_context
{
const double *r1; /* pointers to resistor values */
const double *r2;
const double *r3;
const double *r4;
const double *r5;
const double *r6;
const double *r7;
const double *r8;
int type;
UINT8 flip_flop; /* flip/flop output state */
UINT8 flip_flop_xor; /* flip_flop ^ flip_flop_xor, 0 = discharge, 1 = charge */
UINT8 is_squarewave;
double v_out_high;
double threshold_low; /* falling threshold */
double threshold_high; /* rising threshold */
double v_cap; /* current capacitor voltage */
double r_total; /* all input resistors in parallel */
double i_fixed; /* fixed current at the input */
double temp1; /* Multi purpose */
double temp2; /* Multi purpose */
double temp3; /* Multi purpose */
};
struct dss_sawtoothwave_context
{
double phase;
int type;
};
struct dss_schmitt_osc_context
{
double ration_in; /* ratio of total charging voltage that comes from the input */
double ratio_feedback; /* ratio of total charging voltage that comes from the feedback */
double v_cap; /* current capacitor voltage */
double rc; /* r*c */
double exponent;
int state; /* state of the output */
int enable_type;
UINT8 input_is_voltage;
};
struct dss_sinewave_context
{
double phase;
};
struct dss_squarewave_context
{
double phase;
double trigger;
};
struct dss_squarewfix_context
{
int flip_flop;
double sample_step;
double t_left;
double t_off;
double t_on;
};
struct dss_trianglewave_context
{
double phase;
};
/************************************************************************
*
* DSS_COUNTER - External clock Binary Counter
*
* input0 - Enable input value
* input1 - Reset input (active high)
* input2 - Clock Input
* input3 - Max count
* input4 - Direction - 0=down, 1=up
* input5 - Reset Value
* input6 - Clock type
*
* Jan 2004, D Renaud.
************************************************************************/
#define DSS_COUNTER__ENABLE (*(node->input[0]))
#define DSS_COUNTER__RESET (*(node->input[1]))
#define DSS_COUNTER__CLOCK (*(node->input[2]))
#define DSS_COUNTER__MAX (*(node->input[3]))
#define DSS_COUNTER__DIR (*(node->input[4]))
#define DSS_COUNTER__INIT (*(node->input[5]))
#define DSS_COUNTER__CLOCK_TYPE (*(node->input[6]))
#define DSS_7492__CLOCK_TYPE DSS_COUNTER__MAX
static const int disc_7492_count[6] = {0x00, 0x01, 0x02, 0x04, 0x05, 0x06};
static DISCRETE_STEP(dss_counter)
{
struct dss_counter_context *context = node->context;
double cycles;
int clock = 0, last_count, inc = 0;
int max;
double x_time = 0;
if (context->is_7492)
max = 5;
else
max = DSS_COUNTER__MAX;
if (context->clock_type == DISC_CLK_IS_FREQ)
{
/* We need to keep clocking the internal clock even if disabled. */
cycles = (context->t_left + discrete_current_context->sample_time) / context->t_clock;
inc = (int)cycles;
context->t_left = (cycles - inc) * context->t_clock;
if (inc) x_time = context->t_left / discrete_current_context->sample_time;
}
else
{
clock = (int)DSS_COUNTER__CLOCK;
x_time = DSS_COUNTER__CLOCK - clock;
}
/* If reset enabled then set output to the reset value. No x_time in reset. */
if (DSS_COUNTER__RESET)
{
context->count = DSS_COUNTER__INIT;
node->output[0] = context->count;
return;
}
/*
* Only count if module is enabled.
* This has the effect of holding the output at it's current value.
*/
if (DSS_COUNTER__ENABLE)
{
last_count = context->count;
switch (context->clock_type)
{
case DISC_CLK_ON_F_EDGE:
case DISC_CLK_ON_R_EDGE:
/* See if the clock has toggled to the proper edge */
clock = (clock != 0);
if (context->last != clock)
{
context->last = clock;
if (context->clock_type == clock)
{
/* Toggled */
inc = 1;
}
}
break;
case DISC_CLK_BY_COUNT:
/* Clock number of times specified. */
inc = clock;
break;
}
for (clock = 0; clock < inc; clock++)
{
context->count += DSS_COUNTER__DIR ? 1 : -1; /* up/down */
if (context->count < 0) context->count = max;
if (context->count > max) context->count = 0;
}
node->output[0] = context->is_7492 ? disc_7492_count[context->count] : context->count;
if (context->count != last_count)
{
/* the x_time is only output if the output changed. */
switch (context->out_type)
{
case DISC_OUT_IS_ENERGY:
if (x_time == 0) x_time = 1.0;
node->output[0] = last_count;
if (context->count > last_count)
node->output[0] += (context->count - last_count) * x_time;
else
node->output[0] -= (last_count - context->count) * x_time;
break;
case DISC_OUT_HAS_XTIME:
node->output[0] += x_time;
break;
}
}
}
else
node->output[0] = context->count;
}
static DISCRETE_RESET(dss_counter)
{
struct dss_counter_context *context = node->context;
if ((int)DSS_COUNTER__CLOCK_TYPE & DISC_COUNTER_IS_7492)
{
context->is_7492 = 1;
context->clock_type = (int)DSS_7492__CLOCK_TYPE;
}
else
{
context->is_7492 = 0;
context->clock_type = (int)DSS_COUNTER__CLOCK_TYPE;
}
context->out_type = context->clock_type & DISC_OUT_MASK;
context->clock_type &= DISC_CLK_MASK;
context->t_clock = 1.0 / DSS_COUNTER__CLOCK;
context->t_left = 0;
context->last = 0;
context->count = DSS_COUNTER__INIT; /* count starts at reset value */
node->output[0] = DSS_COUNTER__INIT;
}
/************************************************************************
*
* DSS_LFSR_NOISE - Usage of node_description values for LFSR noise gen
*
* input0 - Enable input value
* input1 - Register reset
* input2 - Clock Input
* input3 - Amplitude input value
* input4 - Input feed bit
* input5 - Bias
*
* also passed dss_lfsr_context structure
*
************************************************************************/
#define DSS_LFSR_NOISE__ENABLE (*(node->input[0]))
#define DSS_LFSR_NOISE__RESET (*(node->input[1]))
#define DSS_LFSR_NOISE__CLOCK (*(node->input[2]))
#define DSS_LFSR_NOISE__AMP (*(node->input[3]))
#define DSS_LFSR_NOISE__FEED (*(node->input[4]))
#define DSS_LFSR_NOISE__BIAS (*(node->input[5]))
static int dss_lfsr_function(int myfunc, int in0, int in1, int bitmask)
{
int retval;
in0 &= bitmask;
in1 &= bitmask;
switch(myfunc)
{
case DISC_LFSR_XOR:
retval = in0 ^ in1;
break;
case DISC_LFSR_OR:
retval = in0 | in1;
break;
case DISC_LFSR_AND:
retval = in0 & in1;
break;
case DISC_LFSR_XNOR:
retval = in0 ^ in1;
retval = retval ^ bitmask; /* Invert output */
break;
case DISC_LFSR_NOR:
retval = in0 | in1;
retval = retval ^ bitmask; /* Invert output */
break;
case DISC_LFSR_NAND:
retval = in0 & in1;
retval = retval ^ bitmask; /* Invert output */
break;
case DISC_LFSR_IN0:
retval = in0;
break;
case DISC_LFSR_IN1:
retval = in1;
break;
case DISC_LFSR_NOT_IN0:
retval = in0 ^ bitmask;
break;
case DISC_LFSR_NOT_IN1:
retval = in1 ^ bitmask;
break;
case DISC_LFSR_REPLACE:
retval = in0 & ~in1;
retval = retval | in1;
break;
case DISC_LFSR_XOR_INV_IN0:
retval = in0 ^ bitmask; /* invert in0 */
retval = retval ^ in1; /* xor in1 */
break;
case DISC_LFSR_XOR_INV_IN1:
retval = in1 ^ bitmask; /* invert in1 */
retval = retval ^ in0; /* xor in0 */
break;
default:
discrete_log("dss_lfsr_function - Invalid function type passed");
retval=0;
break;
}
return retval;
}
/* reset prototype so that it can be used in init function */
static DISCRETE_RESET(dss_lfsr);
static DISCRETE_STEP(dss_lfsr)
{
const discrete_lfsr_desc *lfsr_desc = node->custom;
struct dss_lfsr_context *context = node->context;
double cycles;
int clock, inc = 0;
int fb0, fb1, fbresult;
if (lfsr_desc->clock_type == DISC_CLK_IS_FREQ)
{
/* We need to keep clocking the internal clock even if disabled. */
cycles = (context->t_left + discrete_current_context->sample_time) / context->t_clock;
inc = (int)cycles;
context->t_left = (cycles - inc) * context->t_clock;
}
/* Reset everything if necessary */
if((DSS_LFSR_NOISE__RESET ? 1 : 0) == context->reset_on_high)
{
DISCRETE_RESET_CALL(dss_lfsr);
return;
}
switch (lfsr_desc->clock_type)
{
case DISC_CLK_ON_F_EDGE:
case DISC_CLK_ON_R_EDGE:
/* See if the clock has toggled to the proper edge */
clock = (DSS_LFSR_NOISE__CLOCK != 0);
if (context->last != clock)
{
context->last = clock;
if (lfsr_desc->clock_type == clock)
{
/* Toggled */
inc = 1;
}
}
break;
case DISC_CLK_BY_COUNT:
/* Clock number of times specified. */
inc = (int)DSS_LFSR_NOISE__CLOCK;
break;
}
for (clock = 0; clock < inc; clock++)
{
/* Fetch the last feedback result */
fbresult = (context->lfsr_reg >> lfsr_desc->bitlength) & 0x01;
/* Stage 2 feedback combine fbresultNew with infeed bit */
fbresult = dss_lfsr_function(lfsr_desc->feedback_function1, fbresult, (DSS_LFSR_NOISE__FEED ? 0x01 : 0x00), 0x01);
/* Stage 3 first we setup where the bit is going to be shifted into */
fbresult = fbresult * lfsr_desc->feedback_function2_mask;
/* Then we left shift the register, */
context->lfsr_reg = context->lfsr_reg << 1;
/* Now move the fbresult into the shift register and mask it to the bitlength */
context->lfsr_reg = dss_lfsr_function(lfsr_desc->feedback_function2, fbresult, context->lfsr_reg, (1 << lfsr_desc->bitlength) - 1 );
/* Now get and store the new feedback result */
/* Fetch the feedback bits */
fb0 = (context->lfsr_reg >> lfsr_desc->feedback_bitsel0) & 0x01;
fb1 = (context->lfsr_reg >> lfsr_desc->feedback_bitsel1) & 0x01;
/* Now do the combo on them */
fbresult = dss_lfsr_function(lfsr_desc->feedback_function0, fb0, fb1, 0x01);
context->lfsr_reg = dss_lfsr_function(DISC_LFSR_REPLACE, context->lfsr_reg, fbresult << lfsr_desc->bitlength, (2 << lfsr_desc->bitlength) - 1);
/* Now select the output bit */
if (context->out_is_f0)
node->output[0] = fbresult & 0x01;
else
node->output[0] = (context->lfsr_reg >> lfsr_desc->output_bit) & 0x01;
/* Final inversion if required */
if (context->invert_output) node->output[0] = node->output[0] ? 0 : 1;
/* Gain stage */
node->output[0] = node->output[0] ? DSS_LFSR_NOISE__AMP / 2 : -DSS_LFSR_NOISE__AMP / 2;
/* Bias input as required */
node->output[0] = node->output[0] + DSS_LFSR_NOISE__BIAS;
}
if(!DSS_LFSR_NOISE__ENABLE)
{
node->output[0] = 0;
}
}
static DISCRETE_RESET(dss_lfsr)
{
const discrete_lfsr_desc *lfsr_desc = node->custom;
struct dss_lfsr_context *context = node->context;
int fb0 , fb1, fbresult;
context->reset_on_high = (lfsr_desc->flags & DISC_LFSR_FLAG_RESET_TYPE_H) ? 1 : 0;
context->invert_output = lfsr_desc->flags & DISC_LFSR_FLAG_OUT_INVERT;
context->out_is_f0 = (lfsr_desc->flags & DISC_LFSR_FLAG_OUTPUT_F0) ? 1 : 0;
if ((lfsr_desc->clock_type < DISC_CLK_ON_F_EDGE) || (lfsr_desc->clock_type > DISC_CLK_IS_FREQ))
discrete_log("Invalid clock type passed in NODE_%d\n", NODE_INDEX(node->node));
context->last = (DSS_COUNTER__CLOCK != 0);
if (lfsr_desc->clock_type == DISC_CLK_IS_FREQ) context->t_clock = 1.0 / DSS_LFSR_NOISE__CLOCK;
context->t_left = 0;
context->lfsr_reg = lfsr_desc->reset_value;
/* Now get and store the new feedback result */
/* Fetch the feedback bits */
fb0 = (context->lfsr_reg >> lfsr_desc->feedback_bitsel0) & 0x01;
fb1=(context->lfsr_reg >> lfsr_desc->feedback_bitsel1) & 0x01;
/* Now do the combo on them */
fbresult = dss_lfsr_function(lfsr_desc->feedback_function0, fb0, fb1, 0x01);
context->lfsr_reg=dss_lfsr_function(DISC_LFSR_REPLACE, context->lfsr_reg, fbresult << lfsr_desc->bitlength, (2<< lfsr_desc->bitlength ) - 1);
/* Now select and setup the output bit */
node->output[0] = (context->lfsr_reg >> lfsr_desc->output_bit) & 0x01;
/* Final inversion if required */
if(lfsr_desc->flags & DISC_LFSR_FLAG_OUT_INVERT) node->output[0] = node->output[0] ? 0 : 1;
/* Gain stage */
node->output[0] = node->output[0] ? DSS_LFSR_NOISE__AMP / 2 : -DSS_LFSR_NOISE__AMP / 2;
/* Bias input as required */
node->output[0] = node->output[0] + DSS_LFSR_NOISE__BIAS;
}
/************************************************************************
*
* DSS_NOISE - Usage of node_description values for white nose generator
*
* input0 - Enable input value
* input1 - Noise sample frequency
* input2 - Amplitude input value
* input3 - DC Bias value
*
************************************************************************/
#define DSS_NOISE__ENABLE (*(node->input[0]))
#define DSS_NOISE__FREQ (*(node->input[1]))
#define DSS_NOISE__AMP (*(node->input[2]))
#define DSS_NOISE__BIAS (*(node->input[3]))
static DISCRETE_STEP(dss_noise)
{
struct dss_noise_context *context = node->context;
if(DSS_NOISE__ENABLE)
{
/* Only sample noise on rollover to next cycle */
if(context->phase > (2.0 * M_PI))
{
/* GCC's rand returns a RAND_MAX value of 0x7fff */
int newval = (mame_rand(device->machine) & 0x7fff) - 16384;
/* make sure the peak to peak values are the amplitude */
node->output[0] = DSS_NOISE__AMP / 2;
if (newval > 0)
node->output[0] *= ((double)newval / 16383);
else
node->output[0] *= ((double)newval / 16384);
/* Add DC Bias component */
node->output[0] += DSS_NOISE__BIAS;
}
}
else
{
node->output[0] = 0;
}
/* Keep the new phasor in the 2Pi range.*/
context->phase = fmod(context->phase, 2.0 * M_PI);
/* The enable input only curtails output, phase rotation still occurs. */
/* We allow the phase to exceed 2Pi here, so we can tell when to sample the noise. */
context->phase += ((2.0 * M_PI * DSS_NOISE__FREQ) / discrete_current_context->sample_rate);
}
static DISCRETE_RESET(dss_noise)
{
struct dss_noise_context *context = node->context;
context->phase=0;
DISCRETE_STEP_CALL( dss_noise );
}
/************************************************************************
*
* DSS_NOTE - Note/tone generator
*
* input0 - Enable input value
* input1 - Clock Input
* input2 - data value
* input3 - Max count 1
* input4 - Max count 2
* input5 - Clock type
*
* Mar 2004, D Renaud.
************************************************************************/
#define DSS_NOTE__ENABLE (*(node->input[0]))
#define DSS_NOTE__CLOCK (*(node->input[1]))
#define DSS_NOTE__DATA (*(node->input[2]))
#define DSS_NOTE__MAX1 (*(node->input[3]))
#define DSS_NOTE__MAX2 (*(node->input[4]))
#define DSS_NOTE__CLOCK_TYPE (*(node->input[5]))
static DISCRETE_STEP(dss_note)
{
struct dss_note_context *context = node->context;
double cycles;
int clock = 0, last_count2, inc = 0;
double x_time = 0;
if (context->clock_type == DISC_CLK_IS_FREQ)
{
/* We need to keep clocking the internal clock even if disabled. */
cycles = (context->t_left + discrete_current_context->sample_time) / context->t_clock;
inc = (int)cycles;
context->t_left = (cycles - inc) * context->t_clock;
if (inc) x_time = context->t_left / discrete_current_context->sample_time;
}
else
{
/* Seperate clock info from x_time info. */
clock = (int)DSS_NOTE__CLOCK;
x_time = DSS_NOTE__CLOCK - clock;
}
if (DSS_NOTE__ENABLE)
{
last_count2 = context->count2;
switch (context->clock_type)
{
case DISC_CLK_ON_F_EDGE:
case DISC_CLK_ON_R_EDGE:
/* See if the clock has toggled to the proper edge */
clock = (clock != 0);
if (context->last != clock)
{
context->last = clock;
if (context->clock_type == clock)
{
/* Toggled */
inc = 1;
}
}
break;
case DISC_CLK_BY_COUNT:
/* Clock number of times specified. */
inc = clock;
break;
}
/* Count output as long as the data loaded is not already equal to max 1 count. */
if (DSS_NOTE__DATA != DSS_NOTE__MAX1)
{
for (clock = 0; clock < inc; clock++)
{
context->count1++;
if (context->count1 > context->max1)
{
/* Max 1 count reached. Load Data into counter. */
context->count1 = (int)DSS_NOTE__DATA;
context->count2 += 1;
if (context->count2 > context->max2) context->count2 = 0;
}
}
}
node->output[0] = context->count2;
if (context->count2 != last_count2)
{
/* the x_time is only output if the output changed. */
switch (context->out_type)
{
case DISC_OUT_IS_ENERGY:
if (x_time == 0) x_time = 1.0;
node->output[0] = last_count2;
if (context->count2 > last_count2)
node->output[0] += (context->count2 - last_count2) * x_time;
else
node->output[0] -= (last_count2 - context->count2) * x_time;
break;
case DISC_OUT_HAS_XTIME:
node->output[0] += x_time;
break;
}
}
}
else
node->output[0] = 0;
}
static DISCRETE_RESET(dss_note)
{
struct dss_note_context *context = node->context;
context->clock_type = (int)DSS_NOTE__CLOCK_TYPE & DISC_CLK_MASK;
context->out_type = (int)DSS_NOTE__CLOCK_TYPE & DISC_OUT_MASK;
context->last = (DSS_NOTE__CLOCK != 0);
context->t_left = 0;
context->t_clock = 1.0 / DSS_NOTE__CLOCK;
context->count1 = (int)DSS_NOTE__DATA;
context->count2 = 0;
context->max1 = (int)DSS_NOTE__MAX1;
context->max2 = (int)DSS_NOTE__MAX2;
node->output[0] = 0;
}
/************************************************************************
*
* DSS_OP_AMP_OSC - Op Amp Oscillators
*
* input0 - Enable input value
* input1 - vMod1 (if needed)
* input2 - vMod2 (if needed)
*
* also passed discrete_op_amp_osc_info structure
*
* Mar 2004, D Renaud.
************************************************************************/
#define DSS_OP_AMP_OSC__ENABLE (*(node->input[0]))
#define DSS_OP_AMP_OSC__VMOD1 (*(node->input[1]))
#define DSS_OP_AMP_OSC__VMOD2 (*(node->input[2]))
/* The inputs on a norton op-amp are (info->vP - OP_AMP_NORTON_VBE) */
/* which is the same as the output high voltage. We will define them */
/* the same to save a calculation step */
#define DSS_OP_AMP_OSC_NORTON_VP_IN context->v_out_high
static DISCRETE_STEP(dss_op_amp_osc)
{
const discrete_op_amp_osc_info *info = node->custom;
struct dss_op_amp_osc_context *context = node->context;
double i; /* Charging current created by vIn */
double v = 0; /* all input voltages mixed */
double dt; /* change in time */
double vC; /* Current voltage on capacitor, before dt */
double vCnext = 0; /* Voltage on capacitor, after dt */
double iCharge[2] = {0};
UINT8 force_charge = 0;
UINT8 enable = DSS_OP_AMP_OSC__ENABLE;
dt = discrete_current_context->sample_time; /* Change in time */
vC = context->v_cap; /* Set to voltage before change */
/* work out the charge currents for the VCOs. */
switch (context->type)
{
case DISC_OP_AMP_OSCILLATOR_VCO_1:
/* Work out the charge rates. */
/* i is not a current. It is being used as a temp variable. */
i = DSS_OP_AMP_OSC__VMOD1 * context->temp1;
iCharge[0] = (DSS_OP_AMP_OSC__VMOD1 - i) / info->r1;
iCharge[1] = (i - (DSS_OP_AMP_OSC__VMOD1 * context->temp2)) / context->temp3;
break;
case DISC_OP_AMP_OSCILLATOR_1 | DISC_OP_AMP_IS_NORTON:
{
/* resistors can be nodes, so everything needs updating */
double i1, i2;
/* Work out the charge rates. */
iCharge[0] = DSS_OP_AMP_OSC_NORTON_VP_IN / *context->r1;
iCharge[1] = (context->v_out_high - OP_AMP_NORTON_VBE) / *context->r2 - iCharge[0];
/* Work out the Inverting Schmitt thresholds. */
i1 = DSS_OP_AMP_OSC_NORTON_VP_IN / *context->r5;
i2 = (0.0 - OP_AMP_NORTON_VBE) / *context->r4;
context->threshold_low = (i1 + i2) * *context->r3 + OP_AMP_NORTON_VBE;
i2 = (context->v_out_high - OP_AMP_NORTON_VBE) / *context->r4;
context->threshold_high = (i1 + i2) * *context->r3 + OP_AMP_NORTON_VBE;
break;
}
case DISC_OP_AMP_OSCILLATOR_VCO_1 | DISC_OP_AMP_IS_NORTON:
/* Millman the input voltages. */
if (info->r7 == 0)
{
/* No r7 means that the modulation circuit is fed directly into the circuit. */
v = DSS_OP_AMP_OSC__VMOD1;
}
else
{
/* we need to mix any bias and all modulation voltages together. */
i = context->i_fixed;
i += DSS_OP_AMP_OSC__VMOD1 / info->r7;
if (info->r8 != 0)
i += DSS_OP_AMP_OSC__VMOD2 / info->r8;
v = i * context->r_total;
}
/* Work out the charge rates. */
v -= OP_AMP_NORTON_VBE;
iCharge[0] = v / info->r1;
iCharge[1] = v / info->r2 - iCharge[0];
/* use the real enable circuit */
force_charge = !enable;
enable = 1;
break;
case DISC_OP_AMP_OSCILLATOR_VCO_2 | DISC_OP_AMP_IS_NORTON:
/* Work out the charge rates. */
i = DSS_OP_AMP_OSC__VMOD1 / info->r1;
iCharge[0] = i - context->temp1;
iCharge[1] = context->temp2 - i;
/* if the negative pin current is less then the positive pin current, */
/* then the osc is disabled and the cap keeps charging */
if (iCharge[0] < 0)
{
force_charge = 1;
iCharge[0] *= -1;
}
break;
case DISC_OP_AMP_OSCILLATOR_VCO_3 | DISC_OP_AMP_IS_NORTON:
/* we need to mix any bias and all modulation voltages together. */
iCharge[0] = context->i_fixed;
v = DSS_OP_AMP_OSC__VMOD1 - OP_AMP_NORTON_VBE;
iCharge[0] += v / info->r1;
if (info->r6 != 0)
{
v = DSS_OP_AMP_OSC__VMOD2 - OP_AMP_NORTON_VBE;
iCharge[0] += v / info->r6;
}
iCharge[1] = context->temp1 - iCharge[0];
break;
}
if (enable)
{
int toggled = 0;
/* Keep looping until all toggling in time sample is used up. */
do
{
if ((context->flip_flop ^ context->flip_flop_xor) || force_charge)
{
/* Charging */
/* iC=C*dv/dt works out to dv=iC*dt/C */
vCnext = vC + (iCharge[1] * dt / info->c);
dt = 0;
/* has it charged past upper limit? */
if (vCnext > context->threshold_high)
{
context->flip_flop = context->flip_flop_xor;
toggled++;
if (force_charge)
{
/* we need to keep charging the cap to the max thereby disabling the circuit */
if (vCnext > context->v_out_high)
vCnext = context->v_out_high;
}
else
{
/* calculate the overshoot time */
dt = info->c * (vCnext - context->threshold_high) / iCharge[1];
vC = context->threshold_high;
}
}
}
else
{
/* Discharging */
vCnext = vC - (iCharge[0] * dt / info->c);
dt = 0;
/* has it discharged past lower limit? */
if (vCnext < context->threshold_low)
{
context->flip_flop = !context->flip_flop_xor;
toggled++;
/* calculate the overshoot time */
dt = info->c * (context->threshold_low - vCnext) / iCharge[0];
vC = context->threshold_low;
}
}
} while(dt);
context->v_cap = vCnext;
if (context->is_squarewave)
{
if (toggled == 2)
/* Some oscillators have rapid rise or fall times causing 1 part of the */
/* squarewave to happen in the sample time causing it to be missed. */
/* If we toggle 2 states we force the missed output for 1 sample. */
/* If more then 2 states happen, there is no hope, the sample rate is just too low. */
node->output[0] = context->v_out_high * (context->flip_flop ? 0 : 1);
else
node->output[0] = context->v_out_high * context->flip_flop;
}
else
node->output[0] = context->v_cap;
}
else
{
/* we will just output 0 for oscillators that have no real enable. */
node->output[0] = 0;
}
}
static DISCRETE_RESET(dss_op_amp_osc)
{
const discrete_op_amp_osc_info *info = node->custom;
struct dss_op_amp_osc_context *context = node->context;
const double *r_info_ptr;
const double **r_context_ptr;
int loop;
node_description *r_node;
double i1 = 0; /* inverting input current */
double i2 = 0; /* non-inverting input current */
/* link to resistor static or node values */
r_info_ptr = &info->r1;
r_context_ptr = &context->r1;
for (loop = 0; loop < 8; loop ++)
{
if IS_VALUE_A_NODE(*r_info_ptr)
{
r_node = discrete_find_node(NULL, *r_info_ptr);
*r_context_ptr = &(r_node->output[NODE_CHILD_NODE_NUM((int)*r_info_ptr)]);
}
else
*r_context_ptr = r_info_ptr;
r_info_ptr++;
r_context_ptr++;
}
context->is_squarewave = info->type & DISC_OP_AMP_OSCILLATOR_OUT_SQW;
context->type = info->type & DISC_OP_AMP_OSCILLATOR_TYPE_MASK;
switch (context->type)
{
case DISC_OP_AMP_OSCILLATOR_VCO_1:
/* The charge rates vary depending on vMod so they are not precalculated. */
/* Charges while FlipFlop High */
context->flip_flop_xor = 0;
/* Work out the Non-inverting Schmitt thresholds. */
context->temp1 = (info->vP / 2) / info->r4;
context->temp2 = (info->vP - OP_AMP_VP_RAIL_OFFSET) / info->r3;
context->temp3 = 1.0 / (1.0 / info->r3 + 1.0 / info->r4);
context->threshold_low = context->temp1 * context->temp3;
context->threshold_high = (context->temp1 + context->temp2) * context->temp3;
/* There is no charge on the cap so the schmitt goes high at init. */
context->flip_flop = 1;
/* Setup some commonly used stuff */
context->temp1 = info->r5 / (info->r2 + info->r5); /* voltage ratio across r5 */
context->temp2 = info->r6 / (info->r1 + info->r6); /* voltage ratio across r6 */
context->temp3 = 1.0 / (1.0 / info->r1 + 1.0 / info->r6); /* input resistance when r6 switched in */
break;
case DISC_OP_AMP_OSCILLATOR_1 | DISC_OP_AMP_IS_NORTON:
/* Charges while FlipFlop High */
context->flip_flop_xor = 0;
/* There is no charge on the cap so the schmitt inverter goes high at init. */
context->flip_flop = 1;
break;
case DISC_OP_AMP_OSCILLATOR_VCO_1 | DISC_OP_AMP_IS_NORTON:
/* Charges while FlipFlop Low */
context->flip_flop_xor = 1;
/* There is no charge on the cap so the schmitt goes low at init. */
context->flip_flop = 0;
/* The charge rates vary depending on vMod so they are not precalculated. */
/* But we can precalculate the fixed currents. */
context->i_fixed = 0;
if (info->r6 != 0) context->i_fixed += info->vP / info->r6;
context->i_fixed += OP_AMP_NORTON_VBE / info->r1;
context->i_fixed += OP_AMP_NORTON_VBE / info->r2;
/* Work out the input resistance to be used later to calculate the Millman voltage. */
context->r_total = 1.0 / info->r1 + 1.0 / info->r2 + 1.0 / info->r7;
if (info->r6) context->r_total += 1.0 / info->r6;
if (info->r8) context->r_total += 1.0 / info->r8;
context->r_total = 1.0 / context->r_total;
/* Work out the Non-inverting Schmitt thresholds. */
i1 = (info->vP - OP_AMP_NORTON_VBE) / info->r5;
i2 = (info->vP - OP_AMP_NORTON_VBE - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_low = (i1 - i2) * info->r3 + OP_AMP_NORTON_VBE;
i2 = (0.0 - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_high = (i1 - i2) * info->r3 + OP_AMP_NORTON_VBE;
break;
case DISC_OP_AMP_OSCILLATOR_VCO_2 | DISC_OP_AMP_IS_NORTON:
/* Charges while FlipFlop High */
context->flip_flop_xor = 0;
/* There is no charge on the cap so the schmitt inverter goes high at init. */
context->flip_flop = 1;
/* Work out the charge rates. */
context->temp1 = (info->vP - OP_AMP_NORTON_VBE) / info->r2;
context->temp2 = (info->vP - OP_AMP_NORTON_VBE) * (1.0 / info->r2 + 1.0 / info->r6);
/* Work out the Inverting Schmitt thresholds. */
i1 = (info->vP - OP_AMP_NORTON_VBE) / info->r5;
i2 = (0.0 - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_low = (i1 + i2) * info->r3 + OP_AMP_NORTON_VBE;
i2 = (info->vP - OP_AMP_NORTON_VBE - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_high = (i1 + i2) * info->r3 + OP_AMP_NORTON_VBE;
break;
case DISC_OP_AMP_OSCILLATOR_VCO_3 | DISC_OP_AMP_IS_NORTON:
/* Charges while FlipFlop High */
context->flip_flop_xor = 0;
/* There is no charge on the cap so the schmitt inverter goes high at init. */
context->flip_flop = 1;
/* Work out the charge rates. */
/* The charge rates vary depending on vMod so they are not precalculated. */
/* But we can precalculate the fixed currents. */
if (info->r7 != 0) context->i_fixed = (info->vP - OP_AMP_NORTON_VBE) / info->r7;
context->temp1 = (info->vP - OP_AMP_NORTON_VBE - OP_AMP_NORTON_VBE) / info->r2;
/* Work out the Inverting Schmitt thresholds. */
i1 = (info->vP - OP_AMP_NORTON_VBE) / info->r5;
i2 = (0.0 - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_low = (i1 + i2) * info->r3 + OP_AMP_NORTON_VBE;
i2 = (info->vP - OP_AMP_NORTON_VBE - OP_AMP_NORTON_VBE) / info->r4;
context->threshold_high = (i1 + i2) * info->r3 + OP_AMP_NORTON_VBE;
break;
}
context->v_out_high = info->vP - ((context->type & DISC_OP_AMP_IS_NORTON) ? OP_AMP_NORTON_VBE : OP_AMP_VP_RAIL_OFFSET);
context->v_cap = 0;
DISCRETE_STEP_CALL(dss_op_amp_osc);
}
/************************************************************************
*
* DSS_SAWTOOTHWAVE - Usage of node_description values for step function
*
* input0 - Enable input value
* input1 - Frequency input value
* input2 - Amplitde input value
* input3 - DC Bias Value
* input4 - Gradient
* input5 - Initial Phase
*
************************************************************************/
#define DSS_SAWTOOTHWAVE__ENABLE (*(node->input[0]))
#define DSS_SAWTOOTHWAVE__FREQ (*(node->input[1]))
#define DSS_SAWTOOTHWAVE__AMP (*(node->input[2]))
#define DSS_SAWTOOTHWAVE__BIAS (*(node->input[3]))
#define DSS_SAWTOOTHWAVE__GRAD (*(node->input[4]))
#define DSS_SAWTOOTHWAVE__PHASE (*(node->input[5]))
static DISCRETE_STEP(dss_sawtoothwave)
{
struct dss_sawtoothwave_context *context = node->context;
if(DSS_SAWTOOTHWAVE__ENABLE)
{
node->output[0] = (context->type == 0) ? context->phase * (DSS_SAWTOOTHWAVE__AMP / (2.0 * M_PI)) : DSS_SAWTOOTHWAVE__AMP - (context->phase * (DSS_SAWTOOTHWAVE__AMP / (2.0 * M_PI)));
node->output[0] -= DSS_SAWTOOTHWAVE__AMP / 2.0;
/* Add DC Bias component */
node->output[0] = node->output[0] + DSS_SAWTOOTHWAVE__BIAS;
}
else
{
node->output[0] = 0;
}
/* Work out the phase step based on phase/freq & sample rate */
/* The enable input only curtails output, phase rotation */
/* still occurs */
/* phase step = 2Pi/(output period/sample period) */
/* boils out to */
/* phase step = (2Pi*output freq)/sample freq) */
/* Also keep the new phasor in the 2Pi range. */
context->phase = fmod((context->phase + ((2.0 * M_PI * DSS_SAWTOOTHWAVE__FREQ) / discrete_current_context->sample_rate)), 2.0 * M_PI);
}
static DISCRETE_RESET(dss_sawtoothwave)
{
struct dss_sawtoothwave_context *context = node->context;
double start;
/* Establish starting phase, convert from degrees to radians */
start = (DSS_SAWTOOTHWAVE__PHASE / 360.0) * (2.0 * M_PI);
/* Make sure its always mod 2Pi */
context->phase=fmod(start, 2.0 * M_PI);
/* Invert gradient depending on sawtooth type /|/|/|/|/| or |\|\|\|\|\ */
context->type=(DSS_SAWTOOTHWAVE__GRAD) ? 1 : 0;
/* Step the node to set the output */
DISCRETE_STEP_CALL(dss_sawtoothwave);
}
/************************************************************************
*
* DSS_SCHMITT_OSC - Schmitt feedback oscillator
*
* input0 - Enable input value
* input1 - Vin
* input2 - Amplitude
*
* also passed discrete_schmitt_osc_disc structure
*
* Mar 2004, D Renaud.
************************************************************************/
#define DSS_SCHMITT_OSC__ENABLE (int)(*(node->input[0]))
#define DSS_SCHMITT_OSC__VIN (*(node->input[1]))
#define DSS_SCHMITT_OSC__AMP (*(node->input[2]))
static DISCRETE_STEP(dss_schmitt_osc)
{
const discrete_schmitt_osc_desc *info = node->custom;
struct dss_schmitt_osc_context *context = node->context;
double supply, v_cap, new_vCap, t, exponent;
/* We will always oscillate. The enable just affects the output. */
v_cap = context->v_cap;
exponent = context->exponent;
/* Keep looping until all toggling in time sample is used up. */
do
{
t = 0;
/* The charging voltage to the cap is the sum of the input voltage and the gate
* output voltage in the ratios determined by their resistors in a divider network.
* The input voltage is selectable as straight voltage in or logic level that will
* use vGate as its voltage. Note that ration_in is just the ratio of the total
* voltage and needs to be multipled by the input voltage. ratio_feedback has
* already been multiplied by vGate to save time because that voltage never changes. */
supply = context->input_is_voltage ? context->ration_in * DSS_SCHMITT_OSC__VIN : (DSS_SCHMITT_OSC__VIN ? context->ration_in * info->vGate : 0);
supply += (context->state ? context->ratio_feedback : 0);
new_vCap = v_cap + ((supply - v_cap) * exponent);
if (context->state)
{
/* Charging */
/* has it charged past upper limit? */
if (new_vCap > info->trshRise)
{
/* calculate the overshoot time */
t = context->rc * log(1.0 / (1.0 - ((new_vCap - info->trshRise) / (info->vGate - v_cap))));
/* calculate new exponent because of reduced time */
exponent = RC_CHARGE_EXP_DT(context->rc, t);
v_cap = new_vCap = info->trshRise;
context->state = 0;
}
}
else
{
/* Discharging */
/* has it discharged past lower limit? */
if (new_vCap < info->trshFall)
{
/* calculate the overshoot time */
t = context->rc * log(1.0 / (1.0 - ((info->trshFall - new_vCap) / v_cap)));
/* calculate new exponent because of reduced time */
exponent = RC_CHARGE_EXP_DT(context->rc, t);
v_cap = new_vCap = info->trshFall;
context->state = 1;
}
}
} while(t);
context->v_cap = new_vCap;
switch (context->enable_type)
{
case DISC_SCHMITT_OSC_ENAB_IS_AND:
node->output[0] = DSS_SCHMITT_OSC__ENABLE && context->state;
break;
case DISC_SCHMITT_OSC_ENAB_IS_NAND:
node->output[0] = !(DSS_SCHMITT_OSC__ENABLE && context->state);
break;
case DISC_SCHMITT_OSC_ENAB_IS_OR:
node->output[0] = DSS_SCHMITT_OSC__ENABLE || context->state;
break;
case DISC_SCHMITT_OSC_ENAB_IS_NOR:
node->output[0] = !(DSS_SCHMITT_OSC__ENABLE || context->state);
break;
}
node->output[0] *= DSS_SCHMITT_OSC__AMP;
}
static DISCRETE_RESET(dss_schmitt_osc)
{
const discrete_schmitt_osc_desc *info = node->custom;
struct dss_schmitt_osc_context *context = node->context;
double rSource;
context->enable_type = info->options & DISC_SCHMITT_OSC_ENAB_MASK;
context->input_is_voltage = (info->options & DISC_SCHMITT_OSC_IN_IS_VOLTAGE) ? 1 : 0;
/* The 2 resistors make a voltage divider, so their ratios add together
* to make the charging voltage. */
context->ration_in = info->rFeedback / (info->rIn + info->rFeedback);
context->ratio_feedback = info->rIn / (info->rIn + info->rFeedback) * info->vGate;
/* The voltage source resistance works out to the 2 resistors in parallel.
* So use this for the RC charge constant. */
rSource = 1.0 / ((1.0 / info->rIn) + (1.0 / info->rFeedback));
context->rc = rSource * info->c;
context->exponent = RC_CHARGE_EXP(context->rc);
/* Cap is at 0V on power up. Causing output to be high. */
context->v_cap = 0;
context->state = 1;
node->output[0] = info->options ? 0 : DSS_SCHMITT_OSC__AMP;
}
/************************************************************************
*
* DSS_SINEWAVE - Usage of node_description values for step function
*
* input0 - Enable input value
* input1 - Frequency input value
* input2 - Amplitude input value
* input3 - DC Bias
* input4 - Starting phase
*
************************************************************************/
#define DSS_SINEWAVE__ENABLE (*(node->input[0]))
#define DSS_SINEWAVE__FREQ (*(node->input[1]))
#define DSS_SINEWAVE__AMPL (*(node->input[2]))
#define DSS_SINEWAVE__BIAS (*(node->input[3]))
#define DSS_SINEWAVE__PHASE (*(node->input[4]))
static DISCRETE_STEP(dss_sinewave)
{
struct dss_sinewave_context *context = node->context;
/* Set the output */
if(DSS_SINEWAVE__ENABLE)
{
node->output[0] = (DSS_SINEWAVE__AMPL / 2.0) * sin(context->phase);
/* Add DC Bias component */
node->output[0] = node->output[0] + DSS_SINEWAVE__BIAS;
}
else
{
node->output[0] = 0;
}
/* Work out the phase step based on phase/freq & sample rate */
/* The enable input only curtails output, phase rotation */
/* still occurs */
/* phase step = 2Pi/(output period/sample period) */
/* boils out to */
/* phase step = (2Pi*output freq)/sample freq) */
/* Also keep the new phasor in the 2Pi range. */
context->phase=fmod((context->phase + ((2.0 * M_PI * DSS_SINEWAVE__FREQ) / discrete_current_context->sample_rate)), 2.0 * M_PI);
}
static DISCRETE_RESET(dss_sinewave)
{
struct dss_sinewave_context *context = node->context;
double start;
/* Establish starting phase, convert from degrees to radians */
start = (DSS_SINEWAVE__PHASE / 360.0) * (2.0 * M_PI);
/* Make sure its always mod 2Pi */
context->phase = fmod(start, 2.0 * M_PI);
/* Step the output to make it correct */
DISCRETE_STEP_CALL(dss_sinewave);
}
/************************************************************************
*
* DSS_SQUAREWAVE - Usage of node_description values for step function
*
* input0 - Enable input value
* input1 - Frequency input value
* input2 - Amplitude input value
* input3 - Duty Cycle
* input4 - DC Bias level
* input5 - Start Phase
*
************************************************************************/
#define DSS_SQUAREWAVE__ENABLE (*(node->input[0]))
#define DSS_SQUAREWAVE__FREQ (*(node->input[1]))
#define DSS_SQUAREWAVE__AMP (*(node->input[2]))
#define DSS_SQUAREWAVE__DUTY (*(node->input[3]))
#define DSS_SQUAREWAVE__BIAS (*(node->input[4]))
#define DSS_SQUAREWAVE__PHASE (*(node->input[5]))
static DISCRETE_STEP(dss_squarewave)
{
struct dss_squarewave_context *context = node->context;
/* Establish trigger phase from duty */
context->trigger=((100-DSS_SQUAREWAVE__DUTY)/100)*(2.0*M_PI);
/* Set the output */
if(DSS_SQUAREWAVE__ENABLE)
{
if(context->phase>context->trigger)
node->output[0] = DSS_SQUAREWAVE__AMP /2.0;
else
node->output[0] =- DSS_SQUAREWAVE__AMP / 2.0;
/* Add DC Bias component */
node->output[0] = node->output[0] + DSS_SQUAREWAVE__BIAS;
}
else
{
node->output[0] = 0;
}
/* Work out the phase step based on phase/freq & sample rate */
/* The enable input only curtails output, phase rotation */
/* still occurs */
/* phase step = 2Pi/(output period/sample period) */
/* boils out to */
/* phase step = (2Pi*output freq)/sample freq) */
/* Also keep the new phasor in the 2Pi range. */
context->phase=fmod(context->phase + ((2.0 * M_PI * DSS_SQUAREWAVE__FREQ) / discrete_current_context->sample_rate), 2.0 * M_PI);
}
static DISCRETE_RESET(dss_squarewave)
{
struct dss_squarewave_context *context = node->context;
double start;
/* Establish starting phase, convert from degrees to radians */
start = (DSS_SQUAREWAVE__PHASE / 360.0) * (2.0 * M_PI);
/* Make sure its always mod 2Pi */
context->phase = fmod(start, 2.0 * M_PI);
/* Step the output */
DISCRETE_STEP_CALL(dss_squarewave);
}
/************************************************************************
*
* DSS_SQUAREWFIX - Usage of node_description values for step function
*
* input0 - Enable input value
* input1 - Frequency input value
* input2 - Amplitude input value
* input3 - Duty Cycle
* input4 - DC Bias level
* input5 - Start Phase
*
************************************************************************/
#define DSS_SQUAREWFIX__ENABLE (*(node->input[0]))
#define DSS_SQUAREWFIX__FREQ (*(node->input[1]))
#define DSS_SQUAREWFIX__AMP (*(node->input[2]))
#define DSS_SQUAREWFIX__DUTY (*(node->input[3]))
#define DSS_SQUAREWFIX__BIAS (*(node->input[4]))
#define DSS_SQUAREWFIX__PHASE (*(node->input[5]))
static DISCRETE_STEP(dss_squarewfix)
{
struct dss_squarewfix_context *context = node->context;
context->t_left -= context->sample_step;
/* The enable input only curtails output, phase rotation still occurs */
while (context->t_left <= 0)
{
context->flip_flop = context->flip_flop ? 0 : 1;
context->t_left += context->flip_flop ? context->t_on : context->t_off;
}
if(DSS_SQUAREWFIX__ENABLE)
{
/* Add gain and DC Bias component */
context->t_off = 1.0 / DSS_SQUAREWFIX__FREQ; /* cycle time */
context->t_on = context->t_off * (DSS_SQUAREWFIX__DUTY / 100.0);
context->t_off -= context->t_on;
node->output[0] = (context->flip_flop ? DSS_SQUAREWFIX__AMP / 2.0 : -(DSS_SQUAREWFIX__AMP / 2.0)) + DSS_SQUAREWFIX__BIAS;
}
else
{
node->output[0]=0;
}
}
static DISCRETE_RESET(dss_squarewfix)
{
struct dss_squarewfix_context *context = node->context;
context->sample_step = 1.0 / discrete_current_context->sample_rate;
context->flip_flop = 1;
/* Do the intial time shift and convert freq to off/on times */
context->t_off = 1.0 / DSS_SQUAREWFIX__FREQ; /* cycle time */
context->t_left = DSS_SQUAREWFIX__PHASE / 360.0; /* convert start phase to % */
context->t_left = context->t_left - (int)context->t_left; /* keep % between 0 & 1 */
context->t_left = (context->t_left < 0) ? 1.0 + context->t_left : context->t_left; /* if - then flip to + phase */
context->t_left *= context->t_off;
context->t_on = context->t_off * (DSS_SQUAREWFIX__DUTY / 100.0);
context->t_off -= context->t_on;
context->t_left = -context->t_left;
/* toggle output and work out intial time shift */
while (context->t_left <= 0)
{
context->flip_flop = context->flip_flop ? 0 : 1;
context->t_left += context->flip_flop ? context->t_on : context->t_off;
}
/* Step the output */
DISCRETE_STEP_CALL(dss_squarewfix);
}
/************************************************************************
*
* DSS_SQUAREWAVE2 - Usage of node_description values
*
* input0 - Enable input value
* input1 - Amplitude input value
* input2 - OFF Time
* input3 - ON Time
* input4 - DC Bias level
* input5 - Initial Time Shift
*
************************************************************************/
#define DSS_SQUAREWAVE2__ENABLE (*(node->input[0]))
#define DSS_SQUAREWAVE2__AMP (*(node->input[1]))
#define DSS_SQUAREWAVE2__T_OFF (*(node->input[2]))
#define DSS_SQUAREWAVE2__T_ON (*(node->input[3]))
#define DSS_SQUAREWAVE2__BIAS (*(node->input[4]))
#define DSS_SQUAREWAVE2__SHIFT (*(node->input[5]))
static DISCRETE_STEP(dss_squarewave2)
{
struct dss_squarewave_context *context = node->context;
double newphase;
if(DSS_SQUAREWAVE2__ENABLE)
{
/* Establish trigger phase from time periods */
context->trigger = (DSS_SQUAREWAVE2__T_OFF / (DSS_SQUAREWAVE2__T_OFF + DSS_SQUAREWAVE2__T_ON)) * (2.0 * M_PI);
/* Work out the phase step based on phase/freq & sample rate */
/* The enable input only curtails output, phase rotation */
/* still occurs */
/* phase step = 2Pi/(output period/sample period) */
/* boils out to */
/* phase step = 2Pi/(output period*sample freq) */
newphase = context->phase + ((2.0 * M_PI) / ((DSS_SQUAREWAVE2__T_OFF + DSS_SQUAREWAVE2__T_ON) * discrete_current_context->sample_rate));
/* Keep the new phasor in the 2Pi range.*/
context->phase = fmod(newphase, 2.0 * M_PI);
if(context->phase>context->trigger)
node->output[0] = DSS_SQUAREWAVE2__AMP / 2.0;
else
node->output[0] = -DSS_SQUAREWAVE2__AMP / 2.0;
/* Add DC Bias component */
node->output[0] = node->output[0] + DSS_SQUAREWAVE2__BIAS;
}
else
{
node->output[0] = 0;
}
}
static DISCRETE_RESET(dss_squarewave2)
{
struct dss_squarewave_context *context = node->context;
double start;
/* Establish starting phase, convert from degrees to radians */
/* Only valid if we have set the on/off time */
if((DSS_SQUAREWAVE2__T_OFF + DSS_SQUAREWAVE2__T_ON) != 0.0)
start = (DSS_SQUAREWAVE2__SHIFT / (DSS_SQUAREWAVE2__T_OFF + DSS_SQUAREWAVE2__T_ON)) * (2.0 * M_PI);
else
start = 0.0;
/* Make sure its always mod 2Pi */
context->phase = fmod(start, 2.0 * M_PI);
/* Step the output */
DISCRETE_STEP_CALL(dss_squarewave2);
}
/************************************************************************
*
* DSS_INVERTER_OSC - Usage of node_description values
*
* input0 - Enable input value
* input1 - RC Resistor
* input2 - RP Resistor
* input3 - C Capacitor
* input4 - Desc
*
************************************************************************/
#define DSS_INVERTER_OSC__ENABLE (*(node->input[0]))
#define DSS_INVERTER_OSC__MOD (*(node->input[1]))
#define DSS_INVERTER_OSC__RC (*(node->input[2]))
#define DSS_INVERTER_OSC__RP (*(node->input[3]))
#define DSS_INVERTER_OSC__C (*(node->input[4]))
#define DSS_INVERTER_OSC__R2 (*(node->input[5]))
INLINE double dss_inverter_tftab(node_description *node, double x)
{
const discrete_inverter_osc_desc *info = node->custom;
struct dss_inverter_osc_context *context = node->context;
x = x / info->vB;
if (x > 0)
return info->vB * exp(-context->tf_a * pow(x, context->tf_b));
else
return info->vB;
}
INLINE double dss_inverter_tf(node_description *node, double x)
{
const discrete_inverter_osc_desc *info = node->custom;
struct dss_inverter_osc_context *context = node->context;
if (x < 0.0)
return info->vB;
else if (x <= info->vB)
return context->tf_tab[(int)((double)(DSS_INV_TAB_SIZE - 1) * x / info->vB)];
else
return context->tf_tab[DSS_INV_TAB_SIZE - 1];
}
static DISCRETE_STEP(dss_inverter_osc)
{
struct dss_inverter_osc_context *context = node->context;
const discrete_inverter_osc_desc *info = node->custom;
double diff, vG1, vG2, vG3, vI;
double vMix, rMix;
/* Get new state */
vI = context->v_cap + context->v_g2_old;
switch (info->options & DISC_OSC_INVERTER_TYPE_MASK)
{
case DISC_OSC_INVERTER_IS_TYPE1:
case DISC_OSC_INVERTER_IS_TYPE3:
vG1 = dss_inverter_tf(node, vI);
vG2 = dss_inverter_tf(node, vG1);
vG3 = dss_inverter_tf(node, vG2);
break;
case DISC_OSC_INVERTER_IS_TYPE2:
vG1 = 0;
vG3 = dss_inverter_tf(node, vI);
vG2 = dss_inverter_tf(node, vG3);
break;
case DISC_OSC_INVERTER_IS_TYPE4:
vI = MIN(DSS_INVERTER_OSC__ENABLE, vI + 0.7);
vG1 = 0;
vG3 = dss_inverter_tf(node, vI);
vG2 = dss_inverter_tf(node, vG3);
break;
case DISC_OSC_INVERTER_IS_TYPE5:
vI = MAX(DSS_INVERTER_OSC__ENABLE, vI - 0.7);
vG1 = 0;
vG3 = dss_inverter_tf(node,vI);
vG2 = dss_inverter_tf(node,vG3);
break;
default:
fatalerror("DISCRETE_INVERTER_OSC - Wrong type on NODE_%02d", node->node - NODE_00);
}
switch (info->options & DISC_OSC_INVERTER_TYPE_MASK)
{
case DISC_OSC_INVERTER_IS_TYPE1:
case DISC_OSC_INVERTER_IS_TYPE2:
case DISC_OSC_INVERTER_IS_TYPE3:
if ((info->clamp >= 0.0) && ((vI< - info->clamp) || (vI> info->vB+info->clamp)))
{
vI = MAX(vI, (- info->clamp));
vI = MIN(vI, info->vB + info->clamp);
diff = vG3 * (context->rp / (context->rp + context->r1))
- (context->v_cap + vG2)
+ vI*(context->r1 / (context->rp + context->r1));
diff = diff - diff * context->wc;
}
else
{
diff = vG3 - (context->v_cap + vG2);
diff = diff - diff * context->w;
}
break;
case DISC_OSC_INVERTER_IS_TYPE4:
if ((info->clamp >= 0.0) && ((vI< - info->clamp) || (vI> info->vB+info->clamp)))
{
vI = MAX(vI, (- info->clamp));
vI = MIN(vI, info->vB + info->clamp);
}
/* FIXME handle r2 = 0 */
rMix = (context->r1 * context->r2) / (context->r1 + context->r2);
vMix = rMix* ((vG3 - vG2) / context->r1 + (DSS_INVERTER_OSC__MOD-vG2) / context->r2);
if (vMix < (vI-vG2-0.7))
{
rMix = 1.0 / rMix + 1.0 / context->rp;
rMix = 1.0 / rMix;
vMix = rMix* ( (vG3-vG2) / context->r1 + (DSS_INVERTER_OSC__MOD-vG2) / context->r2 + (vI-0.7-vG2)/context->rp);
}
diff = vMix - context->v_cap;
diff = diff - diff * exp(-discrete_current_context->sample_time / (context->c * rMix));
break;
case DISC_OSC_INVERTER_IS_TYPE5:
if ((info->clamp >= 0.0) && ((vI< - info->clamp) || (vI> info->vB+info->clamp)))
{
vI = MAX(vI, (- info->clamp));
vI = MIN(vI, info->vB + info->clamp);
}
/* FIXME handle r2 = 0 */
rMix = (context->r1 * context->r2) / (context->r1 + context->r2);
vMix = rMix* ((vG3 - vG2) / context->r1 + (DSS_INVERTER_OSC__MOD-vG2) / context->r2);
if (vMix > (vI -vG2 +0.7))
{
rMix = 1.0 / rMix + 1.0/context->rp;
rMix = 1.0 / rMix;
vMix = rMix* ( (vG3 - vG2) / context->r1 + (DSS_INVERTER_OSC__MOD-vG2) / context->r2 + (vI+0.7-vG2)/context->rp);
}
diff = vMix - context->v_cap;
diff = diff - diff * exp(-discrete_current_context->sample_time/(context->c * rMix));
break;
default:
fatalerror("DISCRETE_INVERTER_OSC - Wrong type on NODE_%02d", node->node - NODE_00);
}
context->v_cap += diff;
context->v_g2_old = vG2;
if ((info->options & DISC_OSC_INVERTER_TYPE_MASK) == DISC_OSC_INVERTER_IS_TYPE3)
node->output[0] = vG1;
else
node->output[0] = vG3;
if (info->options & DISC_OSC_INVERTER_OUT_IS_LOGIC)
node->output[0] = (node->output[0] > info->vInFall);
}
static DISCRETE_RESET(dss_inverter_osc)
{
struct dss_inverter_osc_context *context = node->context;
const discrete_inverter_osc_desc *info = node->custom;
int i;
/* exponent */
context->w = exp(-discrete_current_context->sample_time / (DSS_INVERTER_OSC__RC * DSS_INVERTER_OSC__C));
context->wc = exp(-discrete_current_context->sample_time / ((DSS_INVERTER_OSC__RC * DSS_INVERTER_OSC__RP) / (DSS_INVERTER_OSC__RP + DSS_INVERTER_OSC__RC) * DSS_INVERTER_OSC__C));
node->output[0] = 0;
context->v_cap = 0;
context->v_g2_old = 0;
context->rp = DSS_INVERTER_OSC__RP;
context->r1 = DSS_INVERTER_OSC__RC;
context->r2 = DSS_INVERTER_OSC__R2;
context->c = DSS_INVERTER_OSC__C;
context->tf_b = (log(0.0 - log(info->vOutLow/info->vB)) - log(0.0 - log((info->vOutHigh/info->vB))) ) / log(info->vInRise / info->vInFall);
context->tf_a = log(0.0 - log(info->vOutLow/info->vB)) - context->tf_b * log(info->vInRise/info->vB);
context->tf_a = exp(context->tf_a);
for (i = 0; i < DSS_INV_TAB_SIZE; i++)
{
context->tf_tab[i] = dss_inverter_tftab(node, (double)i / (double)(DSS_INV_TAB_SIZE - 1) * info->vB);
}
}
/************************************************************************
*
* DSS_TRIANGLEWAVE - Usage of node_description values for step function
*
* input0 - Enable input value
* input1 - Frequency input value
* input2 - Amplitde input value
* input3 - DC Bias value
* input4 - Initial Phase
*
************************************************************************/
#define DSS_TRIANGLEWAVE__ENABLE (*(node->input[0]))
#define DSS_TRIANGLEWAVE__FREQ (*(node->input[1]))
#define DSS_TRIANGLEWAVE__AMP (*(node->input[2]))
#define DSS_TRIANGLEWAVE__BIAS (*(node->input[3]))
#define DSS_TRIANGLEWAVE__PHASE (*(node->input[4]))
static DISCRETE_STEP(dss_trianglewave)
{
struct dss_trianglewave_context *context = node->context;
if(DSS_TRIANGLEWAVE__ENABLE)
{
node->output[0] = context->phase < M_PI ? (DSS_TRIANGLEWAVE__AMP * (context->phase / (M_PI / 2.0) - 1.0)) / 2.0 :
(DSS_TRIANGLEWAVE__AMP * (3.0 - context->phase / (M_PI / 2.0))) / 2.0 ;
/* Add DC Bias component */
node->output[0] = node->output[0] + DSS_TRIANGLEWAVE__BIAS;
}
else
{
node->output[0] = 0;
}
/* Work out the phase step based on phase/freq & sample rate */
/* The enable input only curtails output, phase rotation */
/* still occurs */
/* phase step = 2Pi/(output period/sample period) */
/* boils out to */
/* phase step = (2Pi*output freq)/sample freq) */
/* Also keep the new phasor in the 2Pi range. */
context->phase=fmod((context->phase + ((2.0 * M_PI * DSS_TRIANGLEWAVE__FREQ) / discrete_current_context->sample_rate)), 2.0 * M_PI);
}
static DISCRETE_RESET(dss_trianglewave)
{
struct dss_trianglewave_context *context = node->context;
double start;
/* Establish starting phase, convert from degrees to radians */
start = (DSS_TRIANGLEWAVE__PHASE / 360.0) * (2.0 * M_PI);
/* Make sure its always mod 2Pi */
context->phase=fmod(start, 2.0 * M_PI);
/* Step to set the output */
DISCRETE_STEP_CALL(dss_trianglewave);
}
/************************************************************************
*
* DSS_ADSR - Attack Decay Sustain Release
*
* input0 - Enable input value
* input1 - Trigger value
* input2 - gain scaling factor
*
************************************************************************/
#define DSS_ADSR__ENABLE (*(node->input[0]))
static DISCRETE_STEP(dss_adsrenv)
{
/* struct dss_adsr_context *context = node->context; */
if(DSS_ADSR__ENABLE)
{
node->output[0] = 0;
}
else
{
node->output[0] = 0;
}
}
static DISCRETE_RESET(dss_adsrenv)
{
DISCRETE_STEP_CALL(dss_adsrenv);
}
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