电路资料

1.防反接：

https://blog.csdn.net/m0_73580268/article/details/131232857

2.stm32最小系统板

https://blog.csdn.net/m0_73580268/article/details/133865193

3.蜂鸣器

https://blog.csdn.net/m0_73580268/article/details/133865230

4.ttl转rs232

https://blog.csdn.net/m0_73580268/article/details/133865757

5.ttl转rs485（自动转换）

https://blog.csdn.net/m0_73580268/article/details/133866139?spm=1001.2014.3001.5502