Workflow

Trigger the first comparison on the comparator channel.

ac_chan_trigger_single_shot(&ac_instance, AC_COMPARATOR_CHANNEL);

2.
Create a local variable to maintain the current comparator state. Since no comparison has taken place, it is initialized to AC_CHAN_STATUS_UNKNOWN.
```
uint8_t last_comparison = AC_CHAN_STATUS_UNKNOWN;
```
3.
Make the application loop infinitely, while performing triggered comparisons.
```
while (true) {
```
4.
Check if the comparator is ready for the last triggered comparison result to be read.
```
if (ac_chan_is_ready(&ac_instance, AC_COMPARATOR_CHANNEL)) {
```

Read the comparator output state into the local variable for application use, re-trying until the comparison state is ready.

do {
    last_comparison = ac_chan_get_status(&ac_instance,
            AC_COMPARATOR_CHANNEL);
} while (last_comparison & AC_CHAN_STATUS_UNKNOWN);

Set the board LED state to mirror the last comparison state.

port_pin_set_output_level(LED_0_PIN,
        (last_comparison & AC_CHAN_STATUS_NEG_ABOVE_POS));

Trigger the next conversion on the Analog Comparator channel.

ac_chan_trigger_single_shot(&ac_instance, AC_COMPARATOR_CHANNEL);