reSIDfp::FilterModelConfig Class Reference

Inheritance diagram for reSIDfp::FilterModelConfig:

Classes
struct	mixer_offset
struct	mixer_offset< 0 >
struct	mixer_offset< 1 >
struct	summer_offset
struct	summer_offset< 0 >

Public Member Functions
unsigned short *	getVolume ()
unsigned short *	getResonance ()
unsigned short *	getSummer ()
unsigned short *	getMixer ()
unsigned short	getOpampRev (int i) const
double	getVddt () const
double	getVth () const
unsigned short	getNormalizedValue (double value) const
template<int N>
unsigned short	getNormalizedCurrentFactor (double wl) const
unsigned short	getNVmin () const
int	getNormalizedVoice (float value, unsigned int env) const

Protected Member Functions
	FilterModelConfig (double vvr, double c, double vdd, double vth, double ucox, const Spline::Point *opamp_voltage, int opamp_size)
void	setUCox (double new_uCox)
virtual double	getVoiceDC (unsigned int env) const =0
void	buildSummerTable (const OpAmp &opampModel)
void	buildMixerTable (const OpAmp &opampModel, double nRatio)
void	buildVolumeTable (const OpAmp &opampModel, double nDivisor)
void	buildResonanceTable (const OpAmp &opampModel, const double resonance_n[16])

Static Protected Member Functions
static unsigned short	to_ushort_dither (double x, double d_noise)
static unsigned short	to_ushort (double x)

Protected Attributes
const double	C
	Capacitor value.
const double	Vdd
	Positive supply voltage.
const double	Vth
	Threshold voltage.
const double	Vddt
	Vdd - Vth.
double	uCox
	Transconductance coefficient: u*Cox.
const double	vmin
const double	vmax
const double	denorm
const double	norm
const double	N16
	Fixed point scaling for 16 bit op-amp output.
const double	voice_voltage_range
double	currFactorCoeff
	Current factor coefficient for op-amp integrators.
unsigned short *	mixer
	Lookup tables for gain and summer op-amps in output stage / filter.
unsigned short *	summer
unsigned short *	volume
unsigned short *	resonance
unsigned short	opamp_rev [1<< 16]
	Reverse op-amp transfer function.

Static Protected Attributes
static constexpr double	Ut = 26.0e-3
	Transistor parameters.

Constructor & Destructor Documentation

FilterModelConfig()

reSIDfp::FilterModelConfig::FilterModelConfig ( double  vvr, double  c, double  vdd, double  vth, double  ucox, const Spline::Point *  opamp_voltage, int  opamp_size  )

protected

Parameters

vvr	voice voltage range
c	capacitor value
vdd	Vdd supply voltage
vth	threshold voltage
ucox	u*Cox
opamp_voltage	opamp voltage array
opamp_size	opamp voltage array size

Member Function Documentation

buildMixerTable()

void reSIDfp::FilterModelConfig::buildMixerTable ( const OpAmp &  opampModel, double  nRatio  )

inlineprotected

The audio mixer operates at n ~ 8/6 (6581) or 8/5 (8580), and has 8 fundamentally different input configurations (0 - 7 input "resistors").

All "on", transistors are modeled as one - see comments above for the filter summer.

buildResonanceTable()

void reSIDfp::FilterModelConfig::buildResonanceTable ( const OpAmp &  opampModel, const double  resonance_n[16]  )

inlineprotected

4 bit "resistor" ladders in the bandpass resonance gain necessitate 16 gain tables. From die photographs of the bandpass "resistor" ladders it follows that 1/Q ~ ~res/8 (6581) or 2^((4 - res)/8) (8580) (assuming ideal op-amps and ideal "resistors").

buildSummerTable()

void reSIDfp::FilterModelConfig::buildSummerTable ( const OpAmp &  opampModel )

inlineprotected

The filter summer operates at n ~ 1, and has 5 fundamentally different input configurations (2 - 6 input "resistors").

Note that all "on" transistors are modeled as one. This is not entirely accurate, since the input for each transistor is different, and transistors are not linear components. However modeling all transistors separately would be extremely costly.

buildVolumeTable()

void reSIDfp::FilterModelConfig::buildVolumeTable ( const OpAmp &  opampModel, double  nDivisor  )

inlineprotected

4 bit "resistor" ladders in the audio output gain necessitate 16 gain tables. From die photographs of the volume "resistor" ladders it follows that gain ~ vol/12 (6581) or vol/16 (8580) (assuming ideal op-amps and ideal "resistors").

getVoiceDC()

virtual double reSIDfp::FilterModelConfig::getVoiceDC ( unsigned int  env ) const

protectedpure virtual

Implemented in reSIDfp::FilterModelConfig6581.

Member Data Documentation

Ut

constexpr double reSIDfp::FilterModelConfig::Ut = 26.0e-3

staticconstexprprotected

Transistor parameters.

Thermal voltage: Ut = kT/q = 8.61734315e-5*T ~ 26mV

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The documentation for this class was generated from the following files:

• FilterModelConfig.h
• FilterModelConfig.cpp