Thanks in advance for your help.
So I'm working on a pressure sensor. The idea is that when the pressure sensor gets to a certain value, say 10 AND then decreases sharply after it has gotten to 10, activate the buzzer. (So it's like, I pump my car tire to 10 and I want to know if there is a leak)
I just for the life of me can not make this happen. I know I'm just missing something very small but I will greatly appreciate any help.
Below is my code:
#include <LiquidCrystal.h> LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
// These constants won't change: const int analogPin = A0; // pin that the sensor is attached to const int ledPin = 13; // pin that the LED is attached to const int threshold = 5; // an arbitrary threshold level that's in the range of the analog input const int buzzer = 9; // pin that the buzzer is connected to.
void setup() { // initialize the LED pin as an output: pinMode(ledPin, OUTPUT); // initilizes the pin as an output. pinMode(buzzer, OUTPUT); // Set buzzer - pin 9 as an output
// initialize serial communications: Serial.begin(9600); lcd.begin(16, 2); lcd.print ("Pressure in kpa"); }
void loop() { // read the value of the pressure sensor: float sensorValue = analogRead(analogPin); // int kpa = (((sensorValue*5)/1024)*(120/5)-116); // 116 was subtracted to equilibrate the sensor int kpa = ((sensorValue * 5 / 1024) * (15 / 5) * (6.894 / 1) - 10); // // if the analog value is greater than whatever threshold we use , turn on the LED:
if (kpa > threshold )
{
digitalWrite(ledPin, HIGH);
digitalWrite(buzzer, HIGH);
tone(buzzer, 1000); // this controls the picth of the sound. (Hz)
delay(1000); } else {
digitalWrite(ledPin, LOW);
digitalWrite(buzzer, LOW);
noTone(buzzer); // Stop sound...
delay(1000); }
// print the analog value: Serial.println(kpa); delay(1); // delay in between reads for stability lcd.setCursor (0, 1); lcd.print (kpa);
}
Thanks.