用vb编写的pid控制程序，可以为做pid控制上位机界面的朋友提供帮助-with vb prepared by the pid control procedures can be done pid control of the PC interface to help a friend

该程序在vb环境实现水位的PID控制，也可以手动设置参数进行开环控制-the procedures in vb environment to achieve the level of PID control, can also manually set parameters for open loop control