？？？从UART转成RS485，wait AT client(uart2) connect timeout(5000 tick).

发布于 2024-07-16 19:54:31 浏览：408 订阅该版

[tocm]

# 🔧硬件配置：
STM32H743IIT6
中移物联网 ML307A-DCLN 4G模块

# 🧾软件环境：
RT-Thread Studio [2.2.6]
rt-thread [4.1.0]
fal [系统组件]
at_device [latest]
ota_downloader [latest]
webclient [v2.2.0]

# 🧷软件包配置：
![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20240716/232ca8dc33b6a44bbb061dc072ac34cd.png)

# 💡目前方案：
之前使用UART2直接连接4G模块进行通信，一切正常。
现在使用RS485与4G模块进行通信，出现`wait AT client(uart2) connect timeout(5000 tick).`

# 🔎其他测试：
![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20240716/4d9f7f906edea31d5e6d4e35e5584eca.png.webp)
```c
[I/at.clnt] AT client(V1.3.1) on device uart2 initialize success.

[18:10:47.647]收←◆[E/at.clnt] wait AT client(uart2) connect timeout(5000 tick).

[18:11:04.767]收←◆[I/at.dev.ml307] ml307 device(ml3070) initialize retry...

[18:11:11.372]收←◆[E/at.clnt] wait AT client(uart2) connect timeout(5000 tick).

[18:11:46.755]收←◆[I/at.dev.ml307] ml307 device(ml3070) initialize retry...

[18:11:53.359]收←◆[E/at.clnt] wait AT client(uart2) connect timeout(5000 tick).

[18:11:54.949]收←◆[I/at.dev.ml307] ml307 device(ml3070) initialize retry...

[18:12:01.554]收←◆[E/at.clnt] wait AT client(uart2) connect timeout(5000 tick).

[18:12:02.559]收←◆[I/at.dev.ml307] ml307 device(ml3070) initialize retry...

[18:12:09.165]收←◆[E/at.clnt] wait AT client(uart2) connect timeout(5000 tick).

[18:12:10.169]收←◆[I/at.dev.ml307] ml307 device(ml3070) initialize retry...
[E/at.dev.ml307] ml307 device(ml3070) network initialize failed(-2)!
```
# ❓问题总结：
为什么分别测试各个部分通信都正常，单片机与4G模块通信就连接超时？？