I do not understand how the direction and speed of the motor can be controlled in below sample code.

Can anyone help to understand the critical timing and purpose of the below code.

#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

// Define the hardware interface
#define MOTOR_PORT GPIOA
#define MOTOR_PIN GPIO_PIN_1

// Define the motor command structure
typedef struct {
    uint8_t speed;
    uint8_t direction;
} motor_command_t;

// Define the task handles
TaskHandle_t command_task_handle;
TaskHandle_t motor_task_handle;

// Define the queue handle
QueueHandle_t command_queue_handle;

// Task to receive motor commands
void command_task(void* pvParameters) {
    motor_command_t command;

    while (1) {
        // Receive a command from the queue
        xQueueReceive(command_queue_handle, &command, portMAX_DELAY);

        // TODO: Process the command, e.g. by validating the speed and direction

        // Send the command to the motor task
        xQueueSendToBack(command_queue_handle, &command, portMAX_DELAY);
    }
}

// Task to control the motor
void motor_task(void* pvParameters) {
    motor_command_t command;

    while (1) {
        // Receive a command from the queue
        xQueueReceive(command_queue_handle, &command, portMAX_DELAY);

        // TODO: Send the command to the motor controller hardware, e.g. by setting the appropriate GPIO pins

        // Wait for the motor to reach the desired speed
        vTaskDelay(pdMS_TO_TICKS(10));

        // TODO: Read the current speed of the motor and adjust as necessary to maintain high fidelity control
    }
}

int main() {
    // Create the command queue
    command_queue_handle = xQueueCreate(10, sizeof(motor_command_t));

    // Create the tasks
    xTaskCreate(command_task, "Command", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, &command_task_handle);
    xTaskCreate(motor_task, "Motor", configMINIMAL_STACK_SIZE, NULL, tskIDLE_PRIORITY + 1, &motor_task_handle);

    // Start the scheduler
    vTaskStartScheduler();

    // The scheduler should never return, but if it does, we'll halt the program
    while (1);
}

 

It would help an awful lot if you let us know what microcontroller, motor controller and power supply you are using and how it is all wired. Without that information, my answer would be just a wild guess.

 

It would help an awful lot if you let us know what microcontroller, motor controller and power supply you are using and how it is all wired. Without that information, my answer would be just a wild guess.

It's been many days. I saved this code on my system when I was searching RTOS related on internet. i don't know the exact link.

I assume 32-bit ARM Cortex-M3 As for motors, brushless DC (BLDC) motors

I just want to know why they used queue in the example.

I just want to understand the basic fundamentals, why queue is used in RTOS