Simple state machine with switch-case in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the state variable.

Embedded C

int state = [1];

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A3

B1

C2

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Starting the state from 1 instead of 0.

Using an uninitialized variable.

The initial state is usually set to 0 to start the state machine.

2fill in blank

medium

Complete the switch statement to check the current state.

Embedded C

switch([1]) {
    case 0:
        // do something
        break;
    case 1:
        // do something else
        break;
}

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Ainput

Bstate

Ccounter

Dflag

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable unrelated to the state machine in the switch.

Forgetting to put the variable inside the switch parentheses.

The switch statement should check the current state variable to decide the action.

3fill in blank

hard

Fix the error in the state update line.

Embedded C

case 0:
    // transition to state 1
    state [1] 1;
    break;

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A=

B=>

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '=' for assignment.

Using invalid operators like '=>'.

Use the assignment operator '=' to update the state variable.

4fill in blank

hard

Fill both blanks to complete the state machine loop and switch.

Embedded C

while([1]) {
    switch([2]) {
        case 0:
            // do something
            state = 1;
            break;
        case 1:
            // do something else
            state = 0;
            break;
    }
}

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A1

Bstate

C0

Drunning

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 in the while condition which stops the loop immediately.

Using a variable other than 'state' in the switch.

The loop runs while true (1), and the switch uses the state variable.

5fill in blank

hard

Fill all three blanks to add a default case and update the state machine.

Embedded C

switch(state) {
    case 0:
        // action for state 0
        state = [1];
        break;
    case 1:
        // action for state 1
        state = [2];
        break;
    default:
        // reset state
        state = [3];
        break;
}

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

A1

B0

C2

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Setting wrong state transitions causing infinite loops.

Not handling the default case properly.

State 0 transitions to 1, state 1 transitions back to 0, and default resets to 0.