rt-thread/bsp/nuvoton/libraries/nu_packages/Demo/usbd_cdc_vcom_echo.c

#include <rtthread.h>

#if defined(RT_USB_DEVICE_CDC) && (defined(BSP_USING_USBD) || defined(BSP_USING_HSUSBD))

static struct rt_semaphore rx_sem;

static rt_err_t uart_input(rt_device_t dev, rt_size_t size)
{
    rt_sem_release(&rx_sem);
    return RT_EOK;
}

static void serial_thread_entry(void *parameter)
{
    rt_device_t serial = (rt_device_t)parameter;
    char ch;
    char szStr[64];
    while (1)
    {
        while (rt_device_read(serial, -1, &ch, 1) != 1)
        {
            if (rt_sem_take(&rx_sem, 3 * RT_TICK_PER_SECOND) == -RT_ETIMEOUT)
            {
                time_t now;
                /* output current time */
                now = time(RT_NULL);
                rt_snprintf(szStr, sizeof(szStr), "%.*s\n", 25, ctime(&now));
                rt_device_write(serial, 0, &szStr[0], rt_strlen(szStr));
                continue;
            }
        }
        rt_device_write(serial, 0, &ch, 1);
    }
}

static int vcom_echo_init(void)
{
    int err = 0;
    rt_thread_t thread;
    rt_device_t serial;

    serial = rt_device_find("vcom");
    if (!serial)
    {
        rt_kprintf("find failed!\n");
        return RT_ERROR;
    }
    err = rt_device_init(serial);
    if (err)
    {
        rt_kprintf("find failed!\n");
        return -RT_ERROR;
    }
    err = rt_device_open(serial, RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX/* | RT_DEVICE_FLAG_DMA_TX */);

    rt_sem_init(&rx_sem, "rx_sem", 0, RT_IPC_FLAG_FIFO);

    rt_device_set_rx_indicate(serial, uart_input);

    thread = rt_thread_create("serial", serial_thread_entry, (void *)serial, 1024, 25, 10);
    if (thread != RT_NULL)
    {
        rt_thread_startup(thread);
    }

    return RT_EOK;
}
INIT_APP_EXPORT(vcom_echo_init);

#endif