The document discusses using a Sharp sensor to measure distance. It provides the formula to calculate distance based on the sensor value. It also provides a sample Arduino program to display the measured distance on an LCD screen, and treats values under 80 as 0 due to the sensor's limited range. Finally, it poses a question about writing a program to control an RGB LED based on distance thresholds.

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3. SHARP SENSOR
 IN AVR ADC IS IS INBUILT SO THERE IS NO NEED OF
EXTERNAL CIRCUIT.
 THIS SHARP SENSOR HAS RANGE OF ONLY 10 TO 80
CM.
 WHEN IT IS OUT OF RANGE THAN IT GIVE RANDOM
VALUE OF DISTANCE.
 DUE TO THIS IN PROGRAM WE USE 0 VALUE WHEN IT
IS OUT OF RANGE.
R-tist
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4. FORMULA FOR DISTANCE
CALCULATION
sensorValue = (6787 / (sensorValue - 3)) - 4;
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5. PROGRAM TO SHOW DIS. ON
SERIAL PORT
 #include <LiquidCrystal.h>  void loop() {
 const int analogInPin = 0;  sensorValue =
 float sensorValue = 0; analogRead(analogInPin);
 LiquidCrystal lcd(4, 7, 8, 9,  lcd.setCursor(0, 0);
12, 13);  if(sensorValue<80)
 void setup() {  sensorValue=0;
 lcd.begin(16, 2);  else
 }  sensorValue = (6787 /
(sensorValue - 3)) - 4;
 lcd.print(sensorValue);
 lcd.print(" ");
 delay(100);
 }
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6. Q-: WRITE A PROGRAM TO
DEMONSTRATE WHEN DISTANCE
OF OBJECT IS LESS THAN 40 CM
THAN RED LED OF RGB IS GLOW
WHEN IT IS 40-50 GREEN LED IS
GLOW AND WHEN IT IS GREATER
THAN 50 BLUE LED GLOW
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