First embedded program (LED blink) in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to turn on the LED by setting the pin high.

Embedded C

PORTB |= (1 << [1]);

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

A5

B7

C1

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong pin number.

Forgetting to use bit shift operator.

Pin 3 is used to control the LED, so setting bit 3 high turns it on.

2fill in blank

medium

Complete the code to configure pin 3 of PORTB as output.

Embedded C

DDRB |= (1 << [1]);

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

A4

B3

C2

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Configuring the wrong pin.

Using '=' instead of '|=' operator.

Setting bit 3 in DDRB configures pin 3 as an output.

3fill in blank

hard

Fix the error in the delay loop to create a visible LED blink.

Embedded C

for (int i = 0; i < [1]; i++) { __asm__("nop"); }

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

A1000

B100

C10

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using too small a delay value.

Forgetting to include the loop.

A delay of 1000 iterations creates a visible blink delay.

4fill in blank

hard

Fill both blanks to toggle the LED on pin 3 of PORTB.

Embedded C

PORTB [1]= (1 << [2]);

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

A^

B|

C3

D&

Attempts:

3 left

💡 Hint

Common Mistakes

Using OR (|) instead of XOR (^).

Using wrong pin number.

Using XOR (^) with bit 3 toggles the LED state.

5fill in blank

hard

Fill all four blanks to create a complete LED blink cycle: turn on, delay, turn off.

Embedded C

PORTB [1]= (1 << [2]);
for (int i = 0; i < [3]; i++) { __asm__("nop"); }
PORTB [4]= ~(1 << [2]);

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

A|=

B3

C1000

D&=

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong operators for turning off the LED.

Delay too short to see blink.

Use '|=' to turn on the LED, delay with 1000 loops, then '&=' with negated bit to turn off.