esp8266连接超时怎么办？

发布于 2022-08-02 23:15:05 浏览：818 订阅该版

3 个回答

crystal266 2022-08-03

嵌入式

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20220803/b73a18f4ca5b3658b19c70c95e2bd973.png.webp)

上图中框选的这句话是在下面这段代码中打印的，说明执行 `AT\r\n` 都没有成功，也就是说模组没有响应，这种情况首先使用串口调试助手直接和模组相连发一下该指令看看有没有响应，有响应表明模组没问题。模组有响应就是程序中串口配置的问题了，再检查一下程序中串口配置的问题（确保模组没有一直处于复位的状态）。

```c
int at_client_obj_wait_connect(at_client_t client, rt_uint32_t timeout)
{
    rt_err_t result = RT_EOK;
    at_response_t resp = RT_NULL;
    rt_tick_t start_time = 0;
    char *client_name = client->device->parent.name;

if (client == RT_NULL)
    {
        LOG_E("input AT client object is NULL, please create or get AT Client object!");
        return -RT_ERROR;
    }

resp = at_create_resp(64, 0, rt_tick_from_millisecond(300));
    if (resp == RT_NULL)
    {
        LOG_E("no memory for AT client(%s) response object.", client_name);
        return -RT_ENOMEM;
    }

rt_mutex_take(client->lock, RT_WAITING_FOREVER);
    client->resp = resp;
    rt_sem_control(client->resp_notice, RT_IPC_CMD_RESET, RT_NULL);

start_time = rt_tick_get();

while (1)
    {
        /* Check whether it is timeout */
        if (rt_tick_get() - start_time > rt_tick_from_millisecond(timeout))
        {
            LOG_E("wait AT client(%s) connect timeout(%d tick).", client_name, timeout);
            result = -RT_ETIMEOUT;
            break;
        }

/* Check whether it is already connected */
        resp->buf_len = 0;
        resp->line_counts = 0;
        at_utils_send(client->device, 0, "AT\r\n", 4);

if (rt_sem_take(client->resp_notice, resp->timeout) != RT_EOK)
            continue;
        else
            break;
    }

at_delete_resp(resp);

client->resp = RT_NULL;

rt_mutex_release(client->lock);

return result;
}
```