Feeding (kicking) the watchdog in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to feed the watchdog by writing the correct function call.

Embedded C

void main() {
    // Feed the watchdog
    [1]();
}

Drag options to blanks, or click blank then click option'

Astop_watchdog

Bstart_watchdog

Ckick_watchdog

Dinit_watchdog

Attempts:

3 left

💡 Hint

Common Mistakes

Using start_watchdog() instead of feeding function.

Using stop_watchdog() which disables the watchdog.

Using init_watchdog() which only initializes but does not feed.

The function kick_watchdog() is used to feed or reset the watchdog timer to prevent system reset.

2fill in blank

medium

Complete the code to initialize the watchdog with a timeout value of 1000 milliseconds.

Embedded C

void setup() {
    watchdog_init([1]);
}

Drag options to blanks, or click blank then click option'

A1000

B500

C2000

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 disables the watchdog timer.

Using 500 or 2000 sets incorrect timeout values.

The watchdog is initialized with a timeout of 1000 milliseconds to reset the system if not fed within this time.

3fill in blank

hard

Fix the error in the watchdog feeding code by completing the missing function call.

Embedded C

int main() {
    while(1) {
        // Feed the watchdog
        [1]();
        delay_ms(500);
    }
    return 0;
}

Drag options to blanks, or click blank then click option'

Ainit_watchdog

Bkick_watchdog

Cwatchdog_stop

Dwatchdog_start

Attempts:

3 left

💡 Hint

Common Mistakes

Using watchdog_start() which only starts but does not feed.

Using watchdog_stop() which disables the watchdog.

Using init_watchdog() which initializes but does not feed.

The correct function to feed the watchdog repeatedly is kick_watchdog(). This prevents the system from resetting.

4fill in blank

hard

Fill both blanks to create a dictionary that maps watchdog states to their descriptions.

Embedded C

const char* watchdog_states[] = {"[1]", "[2]"};

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AACTIVE

BINACTIVE

CSTARTED

DSTOPPED

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'STARTED' and 'STOPPED' which are less common terms.

Mixing up the order of states.

The watchdog states are commonly represented as "ACTIVE" and "INACTIVE" to indicate if it is running or stopped.

5fill in blank

hard

Fill all three blanks to complete the watchdog feeding function with proper checks.

Embedded C

void feed_watchdog() {
    if (watchdog_[1]()) {
        [2]_watchdog();
    } else {
        watchdog_[3]();
    }
}

Drag options to blanks, or click blank then click option'

Ais_running

Bkick

Cstart

Dstop

Attempts:

3 left

💡 Hint

Common Mistakes

Using stop instead of start in the else branch.

Using start instead of kick to feed the watchdog.

Checking wrong status function.

This function checks if the watchdog is running using is_running(). If yes, it feeds the watchdog with kick_watchdog(). Otherwise, it starts the watchdog with start_watchdog().