1602液晶屏的pcb原理图，设计电子时钟。附有C51单片机开发程序等。-Schematic diagram of PCB 1602 LCD screen, electronic clock design. With C51 MCU development program.

52单片机设计程序，包括IO滤波等处理模块，相关单片机设计人员可以参考-52 single-chip design process, including the IO filtering and other processing modules, designers can refer to the relevant microcontroller