Interrupt priority levels in Embedded C - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the priority level of an interrupt to 3.

Embedded C

NVIC_SetPriority(IRQn, [1]);

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A3

B0

C5

D7

Attempts:

3 left

💡 Hint

Common Mistakes

Using a priority level outside the allowed range.

Confusing priority number with interrupt number.

The function NVIC_SetPriority sets the priority of the interrupt. Here, priority level 3 is assigned.

2fill in blank

medium

Complete the code to enable the interrupt with IRQ number 10.

Embedded C

NVIC_EnableIRQ([1]);

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A5

B10

C3

D15

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong IRQ number.

Confusing IRQ number with priority level.

The function NVIC_EnableIRQ enables the interrupt specified by its IRQ number. Here, IRQ 10 is enabled.

3fill in blank

hard

Fix the error in setting the priority level to the highest priority (0).

Embedded C

NVIC_SetPriority(IRQn, [1]);

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A0

B3

C1

D7

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-zero number for highest priority.

Confusing priority levels with IRQ numbers.

Priority 0 is the highest priority level in many embedded systems. Setting it correctly ensures the interrupt has the highest priority.

4fill in blank

hard

Fill both blanks to create a dictionary mapping IRQ numbers to priority levels for IRQ 2 and IRQ 4.

Embedded C

const uint8_t irq_priorities[] = { [[1]] = 1, [[2]] = 3 };

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A2

B1

C4

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping IRQ numbers and priority values.

Using invalid IRQ numbers.

The array sets priority 1 for IRQ 2 and priority 3 for IRQ 4 using designated initializers.

5fill in blank

hard

Fill all three blanks to set priority 2 for IRQ 5, enable IRQ 5, and set priority 0 for IRQ 7.

Embedded C

NVIC_SetPriority([1], 2);
NVIC_EnableIRQ([2]);
NVIC_SetPriority([3], 0);

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

A5

B7

C3

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing IRQ numbers between calls.

Setting wrong priority levels.

The code sets priority 2 for IRQ 5, enables IRQ 5, and sets priority 0 (highest) for IRQ 7.