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#include <avr/interrupt.h>
#include <avr/io.h>
#include <stdint.h>
#include <util/delay.h>
#include "button.h"
#include "display.h"
#include "rtc.h"
// "_gfedcba"
// Reversed because a-g is mapped to pa0-6. (pa7 is decimal)
// Complemented because display is common anode
const uint32_t digit_masks[] = {
0b1000000, 0b1111001, 0b0100100, 0b0110000, 0b0011001,
0b0010010, 0b0000010, 0b1111000, 0b0000000, 0b0010000,
};
void display_setup() {
// Set prescaler CS01 + CS00 (F_CPU / 64) + CTC
// For 32768Hz -> 32768/64 = 512Hz
TCCR0B = (1 << CS01) | (1 << CS00) | (1 << WGM02);
TCCR0A = (1 << WGM01) | (1 << WGM00);
TCNT0 = 0; // Start counting from 0
OCR0A = 1; // 0-1 = 2 counts before timer interrupt (512/2 = 256Hz)
OCR0B = 0;
TIFR0 = (1 << OCF0A) | (1 << OCF0B) | (1 << TOV0); // Clear interrupt flags
TIMSK0 = (1 << OCIE0A); // Enable timer overflow interrupt
// Draw startup state
DDRA |= 0b11111111;
DDRB |= 0b11111111;
PORTA = (1 << PA7);
PORTB = (1 << PB2);
}
volatile uint8_t current_digit = 0;
#define TOTAL_DIGITS 4
// Render current digit
void display_render(void) {
// button_tick(); // Check button click
write_time(minutes, seconds, current_digit);
// Cycle through the 4 digits
current_digit = (current_digit + 1) % TOTAL_DIGITS;
}
inline uint32_t get_digit(uint8_t digit) {
return digit_masks[digit]; // digit % 10
}
void write_time(uint16_t hour, uint16_t minute, uint8_t digit_index) {
uint8_t minute_digit1 = minute % 10;
uint8_t minute_digit2 = (minute / 10) % 10;
// unsigned short hour_digit1 = hour % 10;
// unsigned short hour_digit2 = (hour / 10) % 10;
// reset pins (all output except PA7,PB2)
uint16_t ddra = ~((1 << PA7));
uint16_t ddrb = ~((1 << PB2));
uint16_t porta = 0;
uint16_t portb = 0;
if (digit_index == 0 || digit_index == 2) {
uint32_t segments = get_digit(minute_digit1);
porta = segments;
ddra |= (1 << PA7);
porta |= (1 << PA7);
if (segments & (1 << 6)) {
// If seg inactive, enable other input and enable pull up res
ddrb &= ~(1 << PB2);
portb |= (1 << PB2);
} else {
// If seg active, enable other output and set to 0
ddrb |= (1 << PB2);
portb &= ~(1 << PB2);
}
}
if (digit_index == 1 || digit_index == 3) {
uint32_t segments = get_digit(minute_digit2);
porta = segments;
ddrb |= (1 << PB2);
portb |= (1 << PB2);
if (segments & (1 << 6)) {
// If seg inactive, enable other input and enable pull up res
ddra &= ~(1 << PA7);
porta |= (1 << PA7);
} else {
// If seg active, enable other output and set to 0
ddra |= (1 << PA7);
porta &= ~(1 << PA7);
}
}
// cli();
DDRA = ddra;
DDRB = ddrb;
PORTA = porta;
PORTB = portb;
// sei();
}
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