avr/base/base.h

/*
Copyright 2022, Savanni D'Gerinel <savanni@luminescent-dreams.com>

This file is part of Savanni's AVR library.

Lumeto 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 3 of the License, or (at your option) any later version.

Lumeto 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 Lumeto. If not, see <https://www.gnu.org/licenses/>.
*/

#ifndef __BASE_H__
#define __BASE_H__

#include <avr/io.h>
#include <util/delay.h>

#define LINE_OUT 1
#define LINE_IN  0

typedef struct GPIO {
    volatile uint8_t *ddr;
    volatile uint8_t *port;
    volatile uint8_t *pin;
    uint8_t addr;
} gpio_t;

/*
#define GPIOA(addr) (gpio_t){ .ddr = &DDRA, .port = &PORTA, .addr = addr }
#define GPIOB(addr) (gpio_t){ .ddr = &DDRB, .port = &PORTB, .addr = addr }
#define GPIOC(addr) (gpio_t){ .ddr = &DDRC, .port = &PORTC, .addr = addr }
#define GPIOD(addr) (gpio_t){ .ddr = &DDRD, .port = &PORTD, .addr = addr }
*/

inline void set_line_direction(gpio_t *line, int direction) {
    if (direction == LINE_OUT) {
        *(line->ddr) |= _BV(line->addr);
    } else {
        *(line->ddr) &= ~(_BV(line->addr));
    }
}

inline void set_line(gpio_t *line) {
    *(line->port) |= _BV(line->addr);
}

inline void clear_line(gpio_t *line) {
    *(line->port) &= ~(_BV(line->addr));
}

inline int read_line(gpio_t *line) {
    return (*(line->pin) & _BV(line->addr)) > 0;
}

typedef struct RNG {
    uint8_t mod;
    int8_t a;
    int8_t c;
    uint8_t seed;
} rng_t;

rng_t rng_new(uint8_t seed);

uint8_t rng_sample(rng_t *state);

#endif