sbl::components::control::Pot Class Reference

Potentiometer with EWMA smoothing, deadband, and change detection. More...

#include <pot.hpp>

Collaboration diagram for sbl::components::control::Pot:

Public Member Functions
	Pot (const PotConfig &config={})
void	update (uint16_t raw)
	Feed a new raw ADC sample through EWMA → deadband check.
uint16_t	value () const
	Current stable (deadbanded) value (0-65535)
uint16_t	raw () const
	Last raw (unfiltered) ADC value.
int32_t	scaled (int32_t min, int32_t max) const
	Map stable value to an output range (linear)
int32_t	scaled_curved (int32_t min, int32_t max, uint16_t curve=sbl::dsp::curve::Log) const
	Map stable value with curve shaping.
bool	changed ()
	True if value moved past deadband since last check.
void	set_pickup (uint16_t target)
	Arm pickup mode — freeze output until knob crosses target.
bool	picked_up () const
	True if knob has caught up (or pickup was never armed)
void	clear_pickup ()
	Cancel pickup, resume normal tracking immediately.
void	reset ()
	Reset all state (filter, stable value, changed flag, pickup)

Detailed Description

Potentiometer with EWMA smoothing, deadband, and change detection.

Note

All public methods are ISR-safe — pure state machine with no hardware I/O.

Definition at line 50 of file pot.hpp.

Constructor & Destructor Documentation

Pot()

sbl::components::control::Pot::Pot ( const PotConfig &  config = {} )

inlineexplicit

Definition at line 52 of file pot.hpp.

Member Function Documentation

changed()

bool sbl::components::control::Pot::changed ( )

inline

True if value moved past deadband since last check.

Resets the flag on read — call once per update cycle.

Definition at line 137 of file pot.hpp.

clear_pickup()

void sbl::components::control::Pot::clear_pickup ( )

inline

Cancel pickup, resume normal tracking immediately.

Definition at line 177 of file pot.hpp.

picked_up()

bool sbl::components::control::Pot::picked_up ( ) const

inline

True if knob has caught up (or pickup was never armed)

Definition at line 174 of file pot.hpp.

raw()

uint16_t sbl::components::control::Pot::raw ( ) const

inline

Last raw (unfiltered) ADC value.

Definition at line 100 of file pot.hpp.

References sbl::components::cv::CvInput::raw().

Referenced by update().

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reset()

void sbl::components::control::Pot::reset ( )

inline

Reset all state (filter, stable value, changed flag, pickup)

Definition at line 180 of file pot.hpp.

References sbl::components::cv::CvInput::reset().

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scaled()

int32_t sbl::components::control::Pot::scaled ( int32_t  min, int32_t  max  ) const

inline

Map stable value to an output range (linear)

Linear interpolation from [0, 65535] -> [min, max]. Uses int64_t intermediate to avoid overflow. For non-linear mapping (frequency, filter cutoff), see scaled_curved().

Definition at line 109 of file pot.hpp.

scaled_curved()

int32_t sbl::components::control::Pot::scaled_curved ( int32_t  min, int32_t  max, uint16_t  curve = sbl::dsp::curve::Log  ) const

inline

Map stable value with curve shaping.

Applies ExpCurveWarp::warp() before scaling, useful for knob-friendly non-linear mapping (frequency, filter cutoff, gain).

Parameters

min	Output minimum (inclusive)
max	Output maximum (inclusive)
curve	Shape preset or arbitrary value (see sbl::dsp::curve)

Returns

Scaled value in [min, max]

Definition at line 125 of file pot.hpp.

References sbl::dsp::ExpCurveWarp::warp().

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set_pickup()

void sbl::components::control::Pot::set_pickup ( uint16_t  target )

inline

Arm pickup mode — freeze output until knob crosses target.

The physical knob must cross target (a raw 0-65535 position) before stable_value_ resumes tracking. Until then, value(), scaled(), and scaled_curved() all return values based on target.

Use on mode switch: save the current knob position per-mode, then set_pickup(saved_position) when re-entering that mode.

Parameters

target

The knob position (0-65535) that must be crossed

Definition at line 155 of file pot.hpp.

References sbl::components::cv::CvInput::value().

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update()

void sbl::components::control::Pot::update ( uint16_t  raw )

inline

Feed a new raw ADC sample through EWMA → deadband check.

The EWMA filter smooths the raw value first. Then, if the smoothed value has moved more than deadband from the last stable value, we update the stable value and set the changed flag.

When pickup is armed, the EWMA filter tracks the physical position but stable_value_ stays frozen until the knob crosses the target.

Definition at line 66 of file pot.hpp.

References raw(), sbl::components::cv::CvInput::update(), and sbl::components::cv::CvInput::value().

Referenced by sbl::pot::read(), and sbl::pot::read_dma().

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value()

uint16_t sbl::components::control::Pot::value ( ) const

inline

Current stable (deadbanded) value (0-65535)

Definition at line 97 of file pot.hpp.

Referenced by sbl::pot::read(), and sbl::pot::read_dma().

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

• src/sbl/components/control/pot.hpp