You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
104 lines
2.5 KiB
104 lines
2.5 KiB
#pragma once
|
|
|
|
/**
|
|
An implementation of button debouncer.
|
|
|
|
First, the system must be initialized - even before including:
|
|
|
|
#define DEBO_CHANNELS 2
|
|
#define DEBO_TICKS 5
|
|
|
|
#inclue "lib/debounce.h"
|
|
|
|
A pin is registered like this:
|
|
|
|
#define BTN1 B,0
|
|
#define BTN2 B,1
|
|
|
|
debo_add(BTN0); // The function returns number assigned to the pin (0, 1, ...)
|
|
debo_add_rev(BTN1); // active low
|
|
debo_register(&PINB, PB2, 0); // direct access - register, pin & invert
|
|
|
|
Then periodically call the tick function (perhaps in a timer interrupt):
|
|
|
|
debo_tick();
|
|
|
|
To check if input is active, use
|
|
|
|
debo_get_pin(0); // state of input registered as #0
|
|
debo_get_pin(1); // state of input registered as #1
|
|
*/
|
|
|
|
#include <avr/io.h>
|
|
#include <stdbool.h>
|
|
|
|
#include "calc.h"
|
|
#include "pins.h"
|
|
|
|
|
|
// Number of pins to debounce
|
|
#ifndef DEBO_CHANNELS
|
|
# error "DEBO_CHANNELS not defined!"
|
|
#endif
|
|
|
|
#ifndef DEBO_TICKS
|
|
# warning "DEBO_TICKS not defined, defaulting to 5!"
|
|
# define DEBO_TICKS 5
|
|
#endif
|
|
|
|
|
|
/* Internal deboucer entry */
|
|
typedef struct {
|
|
PORT_P reg;
|
|
uint8_t bit;
|
|
uint8_t count;
|
|
} debo_slot_t;
|
|
|
|
/** Debounce data array */
|
|
debo_slot_t debo_slots[DEBO_CHANNELS];
|
|
uint8_t debo_next_slot = 0;
|
|
|
|
/** Define a debounced pin (must be IO!) */
|
|
|
|
#define debo_add_rev(io) debo_register(&io2pin(io_pack(io)), io2n(io_pack(io)), 1)
|
|
#define debo_add(io) debo_register(&io2pin(io_pack(io)), io2n(io_pack(io)), 0)
|
|
|
|
uint8_t debo_register(PORT_P reg, uint8_t bit, bool invert)
|
|
{
|
|
debo_slots[debo_next_slot] = (debo_slot_t){
|
|
.reg = reg,
|
|
.bit = bit | ((invert & 1) << 7) | (get_bit_p(reg, bit) << 6), // bit 7 = invert, bit 6 = state
|
|
.count = 0,
|
|
};
|
|
|
|
return debo_next_slot++;
|
|
}
|
|
|
|
|
|
/** Check debounced pins, should be called periodically. */
|
|
void debo_tick()
|
|
{
|
|
for (uint8_t i = 0; i < debo_next_slot; i++) {
|
|
// current pin value (right 3 bits, xored with inverse bit)
|
|
bool value = get_bit_p(debo_slots[i].reg, debo_slots[i].bit & 0x7);
|
|
|
|
if (value != get_bit(debo_slots[i].bit, 6)) {
|
|
|
|
// different pin state than last recorded state
|
|
if (debo_slots[i].count < DEBO_TICKS) {
|
|
debo_slots[i].count++;
|
|
} else {
|
|
// overflown -> latch value
|
|
set_bit(debo_slots[i].bit, 6, value); // set state bit
|
|
debo_slots[i].count = 0;
|
|
}
|
|
} else {
|
|
debo_slots[i].count = 0; // reset the counter
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/** Get a value of debounced pin */
|
|
#define debo_get_pin(i) (get_bit(debo_slots[i].bit, 6) ^ get_bit(debo_slots[i].bit, 7))
|
|
//(get_bit(debo_slots[i].bit, 6) ^ get_bit(debo_slots[i].bit, 7))
|
|
|