4、继电器

代码说明：

  基于51单片机的继电器例程，常见问题： 1. 按下按键无效果 确保连线正确 换根杜邦线试试 将单片机拆下来重新安装下，重启开发板(Relay Routine Based on 51 Single Chip Microcomputer, Frequently Asked Questions: 1. Pressing the key has no effect Make sure the connection is correct Try changing the dobang line Remove the microcontroller and reinstall it, restart the development board.)