[Solved] Identify the problem in this FreeRTOS ISR notification code snippet: BaseType_t xHigherPriorityTaskWoken = pdFALSE; xTaskNotifyFromISR(taskHandle, 0x01, eSetBits, &xHigherPriorityTaskWoken);... | FreeRTOS

FreeRTOS - Task Notifications

Identify the problem in this FreeRTOS ISR notification code snippet:

BaseType_t xHigherPriorityTaskWoken = pdFALSE;
xTaskNotifyFromISR(taskHandle, 0x01, eSetBits, &xHigherPriorityTaskWoken);
if (xHigherPriorityTaskWoken) {
    vTaskDelay(10);
}

ACalling vTaskDelay() inside an ISR

BNot checking return value of xTaskNotifyFromISR

CUsing eSetBits instead of eIncrement

DNot clearing notification bits before wait

Step-by-Step Solution

Solution:

Step 1: Understand ISR constraints
Inside an ISR, blocking or delaying functions like vTaskDelay() must not be called.
Step 2: Analyze the code
The code calls vTaskDelay(10) inside the ISR if a higher priority task was woken, which is invalid.
Final Answer:
Calling vTaskDelay() inside an ISR -> Option A
Quick Check:
Delays not allowed in ISR context [OK]

Quick Trick: Never call vTaskDelay inside ISR [OK]

Common Mistakes:

Calling blocking APIs inside ISR
Ignoring xHigherPriorityTaskWoken flag
Misusing notification action parameters

Master "Task Notifications" in FreeRTOS

9 interactive learning modes - each teaches the same concept differently

Learn Why Deep Visual Try Challenge Project Recall Time

More FreeRTOS Quizzes

Identify the problem in this FreeRTOS ISR notification code snippet:

Step 1: Understand ISR constraints

Step 2: Analyze the code

Final Answer:

Quick Check:

Want More Practice?