=>Hi i am goutham i would liketo get details on bidirctional visitor counter without using microcontroller ..My professor Abid ali khan said bidirctional visitor counter without using microcontroller=> will be available here and now i am living in hyderabad and i amstudying in the vasavi college of engineering and now am currently pursuing B.E 3/4 in E.C.E streami need help on the pinciple on how it works by using only simple components
thanking you,
yours sincerely,
goutham
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The circuit operates according to the principle of IR detection. Two sets of IR sensors that consist of an IR LED and phototransistor are placed at two ends. The output of each sensor is fed to the microcontroller. In normal operation, the IR light of the LED would fall on the phototransistor and this led. The output of the sensor would be a low logic signal in this case. In case of any interruption (due to any person crossing the road), the phototransistor would stop driving or drive less and the sensor output would be a high logic signal. The low to high transition for each pair of sensors is detected by the microcontroller and therefore the count would increase or decrease.
Two-way visitor counter circuit diagram:
Circuit Components:
Here is the list of components and their corresponding values used in this circuit.
• R1, R3 - 760 ohms
• R2, R4-3K
• R5 - 10K
• C1 - 10uF, electrolyte
• C2, C3-15pF
• X1 - 12MHz Crystal
• U1 - AT89C51
• U4 - 7 segment 7 segment display
• D1, D2 - LED IR
• Phototransistor Q1, Q2 - IR
It can be understood in the following video:
![[Image: Bi-Directional-Visitor-Counter-Circuit-Diagram.jpg]](http://www.electronicshub.org/wp-content/uploads/2014/04/Bi-Directional-Visitor-Counter-Circuit-Diagram.jpg)
