Design And Research On Taximeter Cheat Checking System

With the developing of economic the taxi has become an important part in city public transportation and closely linked to people’s daily life. Calcualting of the taxi riding cost need the meter. But it may exist cheating and damage the interests of passengers. So more and more people require the meter have the function of examination cheating.This paper firstly introudce the working principle of taximeter. Analising some cheating way in taximeter and getting the main way. By analysing the feature of mormal pulse and getting the difference between the cheating pulse and normal pulse. According the dirrerence to distinguish the taximeter is cheating or not.According to the working principle, this paper propose a two stage data transmission system which composed by board data acquisition systm, relaying system and integrated management system. By comparing research, the wireless communication mode and GPRS to achieve the fuction of data transmission were choosen. Using SCM as the main control chip.Designing the hardware of the system. Highlighting the AT89C52,LM324, short-range signal transmission and receiving module. Then show the schematics of the board data acquisition systm. This paper maily introudce the G200 module in the relay system. For the integrated management system, this paper using TTL-RS485 to convert the voltage level between the G200 and PC.Designing the software in the system. Inculding the data transmission format, encoding format, the subroutine of data transmission or reception and the main program to determining the taximeter is cheating or not.The system was tested in laboratory and practical use. The results show that the system can achieve the desired obiectives and have the advantages of high reliability, ease of use, low cost, and so on.