Code

SAM D20 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM D21 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM R21 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM D11 Xplained Pro.

#define CONF_TC_MODULE TC1

SAM L21 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM L22 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM DA1 Xplained Pro.

#define CONF_TC_MODULE TC3

SAM C21 Xplained Pro.

#define CONF_TC_MODULE TC3

Add to the main application source file, outside of any functions:

struct tc_module tc_instance;

Copy-paste the following callback function code to your user application:

void tc_callback_to_toggle_led(
        struct tc_module *const module_inst)
{
    port_pin_toggle_output_level(LED0_PIN);
}

Copy-paste the following setup code to your user application:

void configure_tc(void)
{
    struct tc_config config_tc;
    tc_get_config_defaults(&config_tc);

    config_tc.counter_size = TC_COUNTER_SIZE_8BIT;
    config_tc.clock_source = GCLK_GENERATOR_1;
    config_tc.clock_prescaler = TC_CLOCK_PRESCALER_DIV1024;
    config_tc.counter_8_bit.period = 100;
    config_tc.counter_8_bit.compare_capture_channel[0] = 50;
    config_tc.counter_8_bit.compare_capture_channel[1] = 54;

    tc_init(&tc_instance, CONF_TC_MODULE, &config_tc);

    tc_enable(&tc_instance);
}

void configure_tc_callbacks(void)
{
    tc_register_callback(&tc_instance, tc_callback_to_toggle_led,
            TC_CALLBACK_OVERFLOW);
    tc_register_callback(&tc_instance, tc_callback_to_toggle_led,
            TC_CALLBACK_CC_CHANNEL0);
    tc_register_callback(&tc_instance, tc_callback_to_toggle_led,
            TC_CALLBACK_CC_CHANNEL1);

    tc_enable_callback(&tc_instance, TC_CALLBACK_OVERFLOW);
    tc_enable_callback(&tc_instance, TC_CALLBACK_CC_CHANNEL0);
    tc_enable_callback(&tc_instance, TC_CALLBACK_CC_CHANNEL1);
}

Add to user application initialization (typically the start of main()):

configure_tc();
configure_tc_callbacks();