Beispiel #1
0
void board_init(void)
{
    /* initialize the boards LEDs, this is done first for debugging purposes */
    leds_init();

    /* Initialize power control pins */
    power_pins_init();

    /* Turn on Vperiph for peripherals */
    gpio_set(MULLE_POWER_VPERIPH);

    /* Turn on AVDD for reading voltages */
    gpio_set(MULLE_POWER_AVDD);

    LED_RED_ON;

    /* Initialize RTC oscillator as early as possible since we are using it as a
     * base clock for the FLL.
     * It takes a while to stabilize the oscillator, therefore we do this as
     * soon as possible during boot in order to let it stabilize while other
     * stuff is initializing. */
    /* If the clock is not stable then the UART will have the wrong baud rate
     * for debug prints as well */
    rtt_init();

    /* Set up clocks */
    set_safe_clock_dividers();

    set_fll_source();

    kinetis_mcg_set_mode(KINETIS_MCG_FEE);

    /* At this point we need to wait for 1 ms until the clock is stable.
     * Since the clock is not yet stable we can only guess how long we must
     * wait. I have tried to make this as short as possible but still being able
     * to read the initialization messages written on the UART.
     * (If the clock is not stable all UART output is garbled until it has
     * stabilized) */
    for (int i = 0; i < 100000; ++i) {
        asm volatile("nop\n");
    }

    /* Update SystemCoreClock global var */
    SystemCoreClockUpdate();

    /* initialize the CPU */
    cpu_init();
}
Beispiel #2
0
void board_init(void)
{
    int status;

    /* initialize the boards LEDs */
    gpio_init(LED0_PIN, GPIO_OUT);
    gpio_init(LED1_PIN, GPIO_OUT);
    gpio_init(LED2_PIN, GPIO_OUT);

    /* Initialize power control pins */
    power_pins_init();

    /* Turn on Vperiph for peripherals */
    /*
     * By turning on Vperiph first, and before waiting for the clocks to
     * stabilize, we will have used enough time to have let the FRAM start up
     * properly when we want to access it later without having to add any extra
     * delays.
     */
    gpio_set(MULLE_POWER_VPERIPH);

    /* Turn on AVDD for reading voltages */
    gpio_set(MULLE_POWER_AVDD);

    /* Initialize RTC oscillator as early as possible since we are using it as a
     * base clock for the FLL.
     * It takes a while to stabilize the oscillator, therefore we do this as
     * soon as possible during boot in order to let it stabilize while other
     * stuff is initializing. */
    /* If the clock is not stable then the UART will have the wrong baud rate
     * for debug prints as well */
    rtt_init();

    /* Set up clocks */
    set_safe_clock_dividers();

    set_fll_source();

    kinetis_mcg_set_mode(KINETIS_MCG_FEE);

    /* At this point we need to wait for 1 ms until the clock is stable.
     * Since the clock is not yet stable we can only guess how long we must
     * wait. I have tried to make this as short as possible but still being able
     * to read the initialization messages written on the UART.
     * (If the clock is not stable all UART output is garbled until it has
     * stabilized) */
    for (int i = 0; i < 100000; ++i) {
        __asm__ volatile("nop\n");
    }

    /* Update SystemCoreClock global var */
    SystemCoreClockUpdate();

    /* initialize the CPU */
    cpu_init();

    /* NVRAM requires xtimer for timing */
    xtimer_init();

    /* Initialize NVRAM */
    status = mulle_nvram_init();
    if (status == 0) {
        /* Increment boot counter */
        increase_boot_count();
    }
}