1.8.1.1.2 Code

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

/* AC module software instance (must not go out of scope while in use) */
static struct ac_module ac_instance;

/* Comparator channel that will be used */
#define AC_COMPARATOR_CHANNEL   AC_CHAN_CHANNEL_0

void configure_ac(void)
{
    /* Create a new configuration structure for the Analog Comparator settings
     * and fill with the default module settings. */
    struct ac_config config_ac;
    ac_get_config_defaults(&config_ac);

    /* Alter any Analog Comparator configuration settings here if required */

    /* Initialize and enable the Analog Comparator with the user settings */
    ac_init(&ac_instance, AC, &config_ac);
}

void configure_ac_channel(void)
{
    /* Create a new configuration structure for the Analog Comparator channel
     * settings and fill with the default module channel settings. */
    struct ac_chan_config ac_chan_conf;
    ac_chan_get_config_defaults(&ac_chan_conf);

    /* Set the Analog Comparator channel configuration settings */
    ac_chan_conf.sample_mode      = AC_CHAN_MODE_SINGLE_SHOT;
    ac_chan_conf.positive_input   = AC_CHAN_POS_MUX_PIN0;
    ac_chan_conf.negative_input   = AC_CHAN_NEG_MUX_SCALED_VCC;
    ac_chan_conf.vcc_scale_factor = 32;

    /* Set up a pin as an AC channel input */
    struct system_pinmux_config ac0_pin_conf;
    system_pinmux_get_config_defaults(&ac0_pin_conf);
    ac0_pin_conf.direction    = SYSTEM_PINMUX_PIN_DIR_INPUT;
    ac0_pin_conf.mux_position = CONF_AC_MUX;
    system_pinmux_pin_set_config(CONF_AC_PIN, &ac0_pin_conf);

    /* Initialize and enable the Analog Comparator channel with the user
     * settings */
    ac_chan_set_config(&ac_instance, AC_COMPARATOR_CHANNEL, &ac_chan_conf);
    ac_chan_enable(&ac_instance, AC_COMPARATOR_CHANNEL);
}

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

system_init();
configure_ac();
configure_ac_channel();
ac_enable(&ac_instance);