Hi,
I've received a load of these slide potentiometers from here: https://www.mouser.co.uk/ProductDetail/Bourns/PTB0153-2010BPB103?qs=oyIm/3giSj5kYFpI22NVZw==
As you can see on the link, these are linear potentiometers. However, when I read them with the Teensy's ADC I get what look very like audio/log values.
Can someone give me a sanity check here, as I'm really confused how this could be the case - I've checked this model on some other major suppliers website and it's also listed as linear. Is it possible that some sort of wiring issue could cause some sort of non-linearality with a linear pot (I'm thinking no, or at least not without the output being essentially noise)?
Here is the code I'm testing with: very vanilla (just a built in Arduino IDE example:
// These constants won't change. They're used to give names to the pins used:
const int analogInPin = A0; // Analog input pin that the potentiometer is attached to
const int analogOutPin = 9; // Analog output pin that the LED is attached to
int sensorValue = 0; // value read from the pot
int outputValue = 0; // value output to the PWM (analog out)
void setup() {
// initialize serial communications at 9600 bps:
Serial.begin(9600);
}
void loop() {
// read the analog in value:
sensorValue = analogRead(analogInPin);
// map it to the range of the analog out:
outputValue = map(sensorValue, 0, 1023, 0, 255);
// change the analog out value:
analogWrite(analogOutPin, outputValue);
// print the results to the Serial Monitor:
Serial.print("sensor = ");
Serial.print(sensorValue);
Serial.print("\t output = ");
Serial.println(outputValue);
// wait 2 milliseconds before the next loop for the analog-to-digital
// converter to settle after the last reading:
delay(2);
}
I've received a load of these slide potentiometers from here: https://www.mouser.co.uk/ProductDetail/Bourns/PTB0153-2010BPB103?qs=oyIm/3giSj5kYFpI22NVZw==
As you can see on the link, these are linear potentiometers. However, when I read them with the Teensy's ADC I get what look very like audio/log values.
Can someone give me a sanity check here, as I'm really confused how this could be the case - I've checked this model on some other major suppliers website and it's also listed as linear. Is it possible that some sort of wiring issue could cause some sort of non-linearality with a linear pot (I'm thinking no, or at least not without the output being essentially noise)?
Here is the code I'm testing with: very vanilla (just a built in Arduino IDE example:
// These constants won't change. They're used to give names to the pins used:
const int analogInPin = A0; // Analog input pin that the potentiometer is attached to
const int analogOutPin = 9; // Analog output pin that the LED is attached to
int sensorValue = 0; // value read from the pot
int outputValue = 0; // value output to the PWM (analog out)
void setup() {
// initialize serial communications at 9600 bps:
Serial.begin(9600);
}
void loop() {
// read the analog in value:
sensorValue = analogRead(analogInPin);
// map it to the range of the analog out:
outputValue = map(sensorValue, 0, 1023, 0, 255);
// change the analog out value:
analogWrite(analogOutPin, outputValue);
// print the results to the Serial Monitor:
Serial.print("sensor = ");
Serial.print(sensorValue);
Serial.print("\t output = ");
Serial.println(outputValue);
// wait 2 milliseconds before the next loop for the analog-to-digital
// converter to settle after the last reading:
delay(2);
}
