At that time, the software could only be written in assembly language, and it was difficult to program and modify. After the HEX file is compiled by ASM51, it is written by a special programmer. Figure 3 shows the software flow chart and assembly language program fragment using AT89C2051.

Pneumatic control valve is especially suitable for special media. Generally speaking, when transporting some harmful and corrosive media, it is also best to use pneumatic control valve. The pneumatic control valves we found in the market usually have the function of fault reset. When purchasing, you can determine the type of pneumatic control valve you want to purchase according to the media you want to transport, so as to prevent the wear of the pneumatic control valve caused by the media problem.