portapack-mayhem/firmware/application/hw/debounce.hpp
Mark Thompson a2a5fb166e
Improved Debounce for Encoders (#1837)
* Fix variable type declaration

* Fix typo

* Two-bit encoder debouncing

* Slight optimization

* Comment change
2024-01-31 14:13:21 -06:00

80 lines
3.0 KiB
C++

/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
*
* This file is part of PortaPack.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef __DEBOUNCE_H__
#define __DEBOUNCE_H__
#include <cstdint>
// consecutive # of times button input must be same (<=8)
#define DEBOUNCE_COUNT 4
#define DEBOUNCE_MASK ((1 << DEBOUNCE_COUNT) - 1)
// # of timer0 ticks before a held button starts being counted as repeated presses
#define REPEAT_INITIAL_DELAY 250
#define REPEAT_SUBSEQUENT_DELAY 92
#define LONG_PRESS_DELAY 800
class Debounce {
public:
bool feed(const uint8_t bit);
uint8_t state();
void enable_repeat();
bool get_long_press_enabled() const;
void set_long_press_enabled(bool v);
bool long_press_occurred();
private:
uint8_t history_{0}; // shift register of last 8 reads from button hardware state bit
uint8_t state_{0}; // actual button hardware state (after debounce logic), 1=pressed
uint8_t state_to_report_{0}; // pseudo button state reported by state() function (may be masked off or simulated presses)
bool repeat_enabled_{false}; // TRUE if this button is enabled to auto-repeat when held down (ignored if long_press_enabled)
uint16_t repeat_ctr_{0}; // used for timing auto-repeat simulated button presses when button is held down and repeat_enabled
uint16_t held_time_{0}; // number of ticks that the button has been held down (compared against REPEAT and LONG_PRESS delays)
bool pulse_upon_release_{false}; // TRUE when button is being held down when long_press_enabled and LONG_PRESS_DELAY hasn't been reached yet
bool simulated_pulse_{false}; // TRUE if a simulated button press is active following a short button press (only when long_press_enabled)
bool long_press_enabled_{false}; // TRUE when button is in long-press mode (takes precedence over the repeat_enabled flag)
bool long_press_occurred_{false}; // TRUE when button is being held down and LONG_PRESS_DELAY has been reached (only when long_press_enabled)
};
class EncoderDebounce {
public:
bool feed(const uint8_t phase_bits); // returns TRUE if state changed after debouncing
uint8_t state(); // returns debounced phase bits from encoder
private:
uint8_t history_{0}; // shift register of previous reads from encoder
uint8_t state_{0}; // actual encoder output state (after debounce logic)
};
#endif /*__DEBOUNCE_H__*/