59 lines
1.7 KiB
C
59 lines
1.7 KiB
C
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#include <stdio.h>
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#include "pico/stdlib.h"
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#include "FreeRTOS.h"
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#include "task.h"
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#include "semphr.h"
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SemaphoreHandle_t xMutex;
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void taskA(void *params) {
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while (1) {
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// Attempt to take the mutex, waiting indefinitely if necessary
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if (xSemaphoreTake(xMutex, portMAX_DELAY) == pdTRUE) {
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// Critical section: Access the shared resource
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printf("Task A: Accessing shared resource\n");
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vTaskDelay(500 / portTICK_PERIOD_MS); // Simulate work by delaying
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// Release the mutex after finishing work
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xSemaphoreGive(xMutex);
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}
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vTaskDelay(1000 / portTICK_PERIOD_MS); // Delay before trying to access again
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}
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}
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void taskB(void *params) {
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while (1) {
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// Attempt to take the mutex, waiting indefinitely if necessary
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if (xSemaphoreTake(xMutex, portMAX_DELAY) == pdTRUE) {
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// Critical section: Access the shared resource
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printf("Task B: Accessing shared resource\n");
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vTaskDelay(500 / portTICK_PERIOD_MS); // Simulate work by delaying
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// Release the mutex after finishing work
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xSemaphoreGive(xMutex);
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}
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vTaskDelay(1500 / portTICK_PERIOD_MS); // Delay before trying to access again
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}
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}
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int main() {
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stdio_init_all(); // Initialize stdio over USB
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// Create a semaphore
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xMutex = xSemaphoreCreateMutex();
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if (xMutex == NULL) {
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printf("Failed to create mutex\n");
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while (1); // Loop forever if mutex creation fails
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}
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xTaskCreate(taskA, "Task A", 1024, NULL, 1, NULL);
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xTaskCreate(taskB, "Task B", 1024, NULL, 1, NULL);
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vTaskStartScheduler(); // Start FreeRTOS scheduler
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for (;;);
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}
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