Hall Sensor Manufacturer tell you the application of the Hall sensor on the taxi meter: the signal detected by the Hall sensor A44E mounted on the wheel is sent to the single chip microcomputer, processed and calculated, and sent to the display unit, thus completing the mileage calculation. The detection principle, P3.2 port as the input end of the signal, the internal use of external interrupt 0, each turn of the wheel (set the circumference of the wheel is 1 m), the Hall switch detects and outputs the signal, causing the interrupt of the micro controller, Pulse counting, when the count reaches 1 000 times, that is, 1 km, the micro controller will automatically increase the amount.
Whenever the Hall Sensor outputs a low level signal, the MCU interrupts once. When the mileage counter counts the mileage pulse for 1 000 times, the program accumulates the current total amount, so that the microcomputer enters the mileage count interrupt service routine. In this program, the accumulation of the current mileage and total amount needs to be completed, and the result is stored in the mileage and total registers.