The implementation of serial communication technology in the vehicle alcohol lock

This paper mainly discusses the upper machine control on the alcohol detection system in the vehicle alcohol lock which can prevent cheating. This system makes use of MSComm(microsoft communications control) to achieve the serial communication between the PC and the PLC. Firstly, the paper describes the modules of the vehicle alcohol lock and its principle. Secondly, we discuss the implementation of the serial communication. Finally, we combine it with the program modules to structure the system based on the difference detection of image by OpenCV. Then we test results of the communication system. We apply the communication protocol between PC and PLC to test by using test assistant. And the results show that the machine can achieve communication between the upper machine and the lower machine.