The circuits driving the ccd and processing the video signal are implemented by means of cpld ( complex programmable logic device ) and hdl ( hardvvare description language ) . the solution to solve the problem of multi - level logical competitive risks that occur in cpld circuits frequently was provided in details in the thesis Ccd的驱动电路和视频信号处理电路采用cpld (可编程逻辑器件)和hdl (硬件描述语言)实现，文章对cpld电路中容易出现的多级逻辑冒险竞争情况作了专门的叙述和提出相应的解决方法。
