Na teraz som zvysil napatie oscilatoru, nechce sa mi previjat ten "proto-netvor".
Vo finale dam viac zavitov.
Frekvenciu oscilatoru som nastavil na 500KHz.
Na Megu som pripojil 20MHz krystal nech mam margin na clocku a teda jednoduchsiu robotu s debouncovanim
Vdaka tomu idem len na interruptoch, ziadne pollovanie bitov a precesavanie v sluckach. Len chytam "hrany".
Zatial to ide na 100% (link video dole), ziadny miss alebo multiple. Iba togglujem ledku. Nemam este rozchodeny displej
https://streamable.com/cvli53
Kod:
Celou podstatou je jedna 3-stavova "state machine" riadena z dvoch interruptov. Jeden interrupt je Pin_Change a druhy Timer.
Princip: Zachytit prvu nabeznu hranu v PCINT (FIRST_CATCH), pockat povedzme 50ms az bude jadro oscilatoru uplne priblizene cievke, opat spustit PCINT, najst nabeznu hranu (SECOND_CATCH), vycitat vstupne piny a v 50ms intervaloch hladat uvolnenie/bezsignalovy stav pinu (FIND_FREE).
Pri hladani nabeznej hrany (SECOND_CATCH) je pridany povedzme 50us timeout ak by sa hranu nepodario najst a program tak neostal vysiet.
Spolieham sa, ze skocenie do PCINT zoberie asi 4 clocky (mozno viac), takze vycitanie
port_state = PIND; hned na zaciatku PCINT odvzorkuje bajoko stred kopceka sinusu.
V main() je iba togglovanie ledky.
Kód: Vybrať všetko
#include<avr/io.h>
#include<avr/interrupt.h>
#define PIN_CH_INT_OFF PCICR &= ~(1 << PCIE3) //pin change int. OFF
#define PIN_CH_INT_ON PCICR |= (1 << PCIE3) //pin change int. ON
#define TIM_OFF TIMSK1 &= ~(1 << TOIE1) //timer off
#define TIM_ON TIMSK1 |= (1 << TOIE1)
enum debouncing_states {
FIRST_CATCH,
SECOND_CATCH,
FIND_FREE
};
volatile enum debouncing_states debouncing_state = FIRST_CATCH;
volatile unsigned char buttons = 0;
volatile unsigned char button_catched = 0;
volatile unsigned char button_int_occured = 0;
ISR(PCINT3_vect) {
unsigned char port_state = PIND;
switch(debouncing_state) {
case FIRST_CATCH:
if(port_state > 0) {
PIN_CH_INT_OFF;
TCNT1 = 50000; //50ms
TIM_ON;
}
break;
case SECOND_CATCH: //moze skocit viac krat
if(port_state > 0) { //button catched
buttons = port_state; //mozno doplnit kontrolu ci je port nenulovy
PIN_CH_INT_OFF;
button_catched = 1;
}
break;
case FIND_FREE:
PIN_CH_INT_OFF;
button_int_occured = 1;
break;
default:
break;
}
}
ISR(TIMER1_OVF_vect) {
switch(debouncing_state) {
case FIRST_CATCH:
debouncing_state = SECOND_CATCH;
button_catched = 0;
TCNT1 = 65520; //timeout 50us if second_catch not occur
PIN_CH_INT_ON;
break;
case SECOND_CATCH:
if(button_catched == 0) { //timeout , ak nenastal interrupt pri SECOND_CATCH
debouncing_state = FIRST_CATCH; //naspat na prve chytanie
TIM_OFF;
} else {
debouncing_state = FIND_FREE;
button_int_occured = 0;
TCNT1 = 50000; //50ms
}
PIN_CH_INT_ON;
break;
case FIND_FREE:
if(button_int_occured == 0) { //ak nenastal interrupt pri FIND FREE
debouncing_state = FIRST_CATCH;
TIM_OFF;
} else {
button_int_occured = 0; //vyskusaj znova
TCNT1 = 50000; //50ms
}
PIN_CH_INT_ON; //zapni tak ci onak
break;
default:
break;
}
}
int main (void) {
DDRB |= (1 << 0); //Led - output
PORTB &= ~(1 << 0);
DDRD = 0; //tlacitka - input
PORTD = 0; //tlacitka - no pull-up
///SET PIN CHANGE INTERRUPT
PCICR |= (1 << PCIE3);
PCMSK3 |= (1 << PCINT24);
///SET DEBOUNCING TIMER clk/64
TCCR1B |= (1 << CS10);
TCCR1B |= (1 << CS11);
sei();
while(1) {
if(buttons > 0) {
buttons = 0;
PORTB ^= (1 << 0);
}
}
}
