avr/lantern-controller/main.c

#include <avr/interrupt.h>
#include <avr/sleep.h>
#include <dio.h>
#include <rfm.h>
#include <stdbool.h>
#include <string.h>

typedef enum {
    lme_off,
    lme_normal,
    lme_spooky,
    lme_eerie,
} lantern_msg_e;

dio_t buttons[4] = {
    { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 5 },
    { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 6 },
    { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 7 },
    { .ddr = &DDRD, .port = &PORTD, .pin = &PIND, .addr = 6 },
};

typedef struct {
    bool button_press[4];
} status_flags_t;

status_flags_t status_flags = {
    .button_press = { false, false, false, false }
};

ISR(INT2_vect) {
    for (int i = 0; i < 4; i++) {
        status_flags.button_press[i] = dio_read(&buttons[i]);
    }
}

int main(void) {
    EIMSK = 1 << INT2;
    EICRA |= 1 << ISC21 | 1 << ISC20;

    dio_t int2 = { .ddr = &DDRD, .port = &PORTD, .pin = &PIND, .addr = 2 };
    dio_set_direction(&int2, LINE_IN);
    dio_set(&int2, false);

    rfm_t radio = (rfm_t){
        .spi    = {
            .clock          = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 1 },
            .data_out       = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 2 },
            .data_in        = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 3 },
            .chip_select    = { .ddr = &DDRB, .port = &PORTB, .pin = &PINB, .addr = 4 },
        },
        .irq    = { .ddr = &DDRE, .port = &PORTE, .pin = &PINE, .addr = 6 },
        .reset  = { .ddr = &DDRD, .port = &PORTD, .pin = &PIND, .addr = 4 },
    };

    rfm_error_e error;
    rfm_init(&radio, (uint8_t [4]){ 0xde, 0xca, 0xfb, 0xad }, 4, &error);

    set_sleep_mode(SLEEP_MODE_IDLE);
    while(1) {
        sei();
        sleep_mode();
        cli();

        uint8_t msg;
        if (status_flags.button_press[0]) {
            status_flags.button_press[0] = false;
            msg = lme_normal;
        } else if (status_flags.button_press[1]) {
            status_flags.button_press[1] = false;
            msg = lme_spooky;
        } else if (status_flags.button_press[2]) {
            status_flags.button_press[2] = false;
            msg = lme_eerie;
        } else if (status_flags.button_press[3]) {
            status_flags.button_press[3] = false;
            msg = lme_off;
        } else {
            continue;
        }

        rfm_transmit(&radio, &msg, 1);

        interrupt_flags_t flags = rfm_interrupts(&radio);
        while(!flags.packet_sent) {
            _delay_ms(1);
            flags = rfm_interrupts(&radio);
        }
        rfm_standby(&radio);
    }
}