I'm a starter with arduino. I tried to sample a 200 Hz sine wave or a square wave from the function generator and get the pulses from an analog output. Ideally, if it is a square wave, I would get the exactly the same pusles from the output. But the pulses I got varied in pulse widths, in other words, the duty cycle was not constantly 50% as the input. I assume there must be problems with sampling rate and PWM frequency. Can anyone help please?
Here's the code I get from the "Analog serial in out" example.
const int analogInPin = A0; // Analog input pin that the function generator 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);
}