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→Méthode par lecture Analogique de la tension
That is, the voltage is proportional to the '''inverse''' of the FSR resistance.
That is, the voltage is proportional to the '''inverse''' of the FSR resistance.
=== Exemple simple ===
Wire the FSR as same as the above example, but this time lets add an LED to pin 11.
[[Fichier:FSR-SAMLE1.jpg]]
[[Fichier:FSR-SAMLE2.jpg]]
This sketch will take the analog voltage reading and use that to determine how bright the red LED is. The harder you press on the FSR, the brighter the LED will be! Remember that the LED has to be connected to a PWM pin for this to work, I use pin 11 in this example.
These examples assume you know some basic Arduino programming.
<nowiki>
/* FSR testing sketch.
Connect one end of FSR to 5V, the other end to Analog 0.
Then connect one end of a 10K resistor from Analog 0 to ground
Connect LED from pin 11 through a resistor to ground
For more information see www.ladyada.net/learn/sensors/fsr.html */
int fsrAnalogPin = 0; // FSR is connected to analog 0
int LEDpin = 11; // connect Red LED to pin 11 (PWM pin)
int fsrReading; // the analog reading from the FSR resistor divider
int LEDbrightness;
void setup(void) {
Serial.begin(9600); // We'll send debugging information via the Serial monitor
pinMode(LEDpin, OUTPUT);
}
void loop(void) {
fsrReading = analogRead(fsrAnalogPin);
Serial.print("Analog reading = ");
Serial.println(fsrReading);
// we'll need to change the range from the analog reading (0-1023) down to the range
// used by analogWrite (0-255) with map!
LEDbrightness = map(fsrReading, 0, 1023, 0, 255);
// LED gets brighter the harder you press
analogWrite(LEDpin, LEDbrightness);
delay(100);
}
</nowiki>
== Mesures FSR analogique (code simple) ===
Here is a code example for measuring the FSR on an analog pin.
[[Fichier:FSR-SAMLE2-1.jpg]]
[[Fichier:FSR-SAMLE2-2.jpg]]
[[Fichier:FSR-SAMLE2-3.jpg]]
This code doesn't do any calculations, it just prints out what it interprets as the amount of pressure in a qualitative manner. For most projects, this is pretty much all thats needed!
<nowiki>
/* FSR simple testing sketch.
Connect one end of FSR to power, the other end to Analog 0.
Then connect one end of a 10K resistor from Analog 0 to ground
For more information see www.ladyada.net/learn/sensors/fsr.html */
int fsrPin = 0; // the FSR and 10K pulldown are connected to a0
int fsrReading; // the analog reading from the FSR resistor divider
void setup(void) {
// We'll send debugging information via the Serial monitor
Serial.begin(9600);
}
void loop(void) {
fsrReading = analogRead(fsrPin);
Serial.print("Analog reading = ");
Serial.print(fsrReading); // the raw analog reading
// We'll have a few threshholds, qualitatively determined
if (fsrReading < 10) {
Serial.println(" - No pressure");
} else if (fsrReading < 200) {
Serial.println(" - Light touch");
} else if (fsrReading < 500) {
Serial.println(" - Light squeeze");
} else if (fsrReading < 800) {
Serial.println(" - Medium squeeze");
} else {
Serial.println(" - Big squeeze");
}
delay(1000);
}
</nowiki>
== Source ==
== Source ==