程序采用单片机的定时器产生一个时钟，作为ADC0809的CLK时钟。并读取A/D的值，同时转换为十进制，后送到LED显示。单片机C语言编译软件用著名Keil C51编译器，Keil C51是德国Keil Software公司出品的51系列兼容单片机C语言软件开发系统，与汇编相比，C语言在功能上、结构性、可读性、可维护性上有明显的优势，因而易学易用，本次ADC程序就是基于Keil C编写出来的。

总的C语言程序由LED显示模块，进制转换模块，ADC模块，主函数构成。-The program uses the MCU timer to produce a clock, as the ADC0809' s CLK clock. And read the value of the A/D converted to decimal and sent to the LED display. Microcontroller C language compiler software using the famous Keil C51 compiler, Keil C51 Germany Keil Software company produced 51 series compatible microcontroller C language software development system, compared with assembler, C language function, structural, readability can be maintenance of the obvious advantages, and thus easy to learn and use, the ADC program is written based Keil C. The total C language program LED display module, binary conversion module, ADC module, the main function.