main.c

#include    <util/delay.h>
#include    <avr/io.h>
#include    <avr/interrupt.h>
#include    <avr/pgmspace.h>
#include    <stdio.h>
#include    <stdlib.h>
#include    <stdint.h>
#include    <string.h>
#include    "can.h"
#include    "uart.h"

//-----UART-Setup-----
#define PRINT(string, ...)      printf_P(PSTR(string), ##__VA_ARGS__)
static int putchar__(char c, FILE *stream) {
    uart_putc(c);
    return 0;
}
static FILE mystdout = FDEV_SETUP_STREAM(putchar__, 0, _FDEV_SETUP_WRITE);
//--------------------

void delay(int sleep);

void init(void){
    uart_init(UART_BAUD_SELECT(9600, F_CPU));
    stdout = &mystdout;
    sei();

    PRINT("Trying to init CAN...");
    delay(1000);

    // Initialize MCP2515
    if (!can_init(BITRATE_125_KBPS)) {
        PRINT("ERROR!\n\rError: Could not init CAN! Check Config!\n\r");
        for (;;);
    }
    else {
        PRINT("OK!\n\r");
    }
}

int main(void)
{
    init();
    PRINT("Initialization complete!\n\r\n\r");
    PRINT("°°° Olimex AVR-CAN with UART, CAN and I2C-Connectivity °°°\n\r");

    can_t msg;
    msg.id = 0x12;
    msg.length = 2;
    msg.data[0] = 0xAB;
    msg.data[1] = 0xCD;
    can_filter_t filter = {
        .id = 0,
        .mask = 0,
        .flags = {
            .rtr = 0
        }
    };

    can_set_filter(0, &filter);
    can_set_mode(LOOPBACK_MODE);


    for(;;) {

        if(!can_send_message(&msg)) PRINT("Could not send!\n\r");
        delay(300);
        if(can_check_message()) {
            PRINT("\n\rGot Something...\n\r");
        } else PRINT(".");

    }
    return 0;
}

void delay(int sleep)
{
    for(int x=0; x<=sleep; x++) {
        _delay_ms(1);
    }
}