User manual

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in up and down modes depending upon the state of the selector. It can be used
to count the number of persons entering a hall in the up mode at entrance gate. In the
down mode, it can count the number of persons leaving the room by
decrementing the count at exit gate. It can also be used at gates of parking areas and
other public places. This circuit divided in three parts: sensor, microcontroller and
counter display. The sensor would observe an interruption and provide an input to
the controller which would run the counter in up/down mode depending upon the
selector setting. Based on the distance sensor that will be used in this system, the
distance is the main factor that will affect the output of the sensor. However, the
output will be the type of analog and in this stage; an analog to digital programming
converter will be needed to convert to the analog to digital output. In the range of 10
to 80 cm from the side of the door, sensor will sense the present of visitor, send
signal to microcontroller and save the updated data. All the data will be displayed on
16 x 2 characters LCD display with yellow backlight through the controller.
Once the visitor enters the room, sensor will detect the present of people and
counter will start to count up and vice versa. The counter will send signal to relay to
turn on the lighting system as the counter start to detect one visitor and above while
the relay will turn off only if the counter hit zero. For convenient, this counter can be
reset by administrator and any error on the counter can be repair.
Figure 2.1 : Counter [14]