很好的知识网站博客

1.MDK自动初始化函数利用__attribute__((section("name")))构建初始化函数表

https://www.cnblogs.com/AresGuangjie/p/12392892.html

 2.rt-thread或者运行hal库时，jlink莫名报错

https://blog.csdn.net/u012388993/article/details/61912976

3.运行在单片机上的shell命令行

https://github.com/NevermindZZT/letter-shell/tree/shell2.x

4.简易的modbus协议

https://github.com/Jancd/modbus

5.simcom联网 

https://www.cnblogs.com/jiangzhaowei/p/9291111.html