Sensor for DIY ventilator

Projects General Guidance
26

5kPa is about 51 cmH2O, see if this works. Watch the ADC value and set variable "offset" correctly if it's not 102 @ 0 pressure.

void setup()
{
  Serial.begin(9600);

}

void loop()
{
  int val, // ADC value
      offset = 102, // ADC value @ 0 pressure
      adcMax = 921, // ADC value @ 5kPa (51 cmH2O)
      span = adcMax - offset; // 819 here

  val = analogRead(A0);
  Serial.print(val); Serial.print("\t");
  val -= offset;
  float pressure = val * 51.0 / span;
  Serial.println(pressure,1); // cmH2O
  delay(2000);
}