analogReadResolution() is an extension of the Analog API for the Arduino Due and Zero.
Sets the size (in bits) of the value returned by analogRead(). It defaults to 10 bits (returns values between 0-1023) for backward compatibility with AVR based boards.
The Due and the Zero have 12-bit ADC capabilities that can be accessed by changing the resolution to 12. This will return values from analogRead() between 0 and 4095.
analogReadResolution(bits) //bits: determines the resolution (in bits) of the value returned by analogRead() function. You can set this 1 and 32. You can set resolutions higher than 12 but values returned by analogRead() will suffer approximation. See the note below for details.
void setup() { // open a serial connection Serial.begin(9600); } void loop() { // read the input on A0 at default resolution (10 bits) // and send it out the serial connection analogReadResolution(10); Serial.print("ADC 10-bit (default) : "); Serial.print(analogRead(A0)); // change the resolution to 12 bits and read A0 analogReadResolution(12); Serial.print(", 12-bit : "); Serial.print(analogRead(A0)); // change the resolution to 16 bits and read A0 analogReadResolution(16); Serial.print(", 16-bit : "); Serial.print(analogRead(A0)); // change the resolution to 8 bits and read A0 analogReadResolution(8); Serial.print(", 8-bit : "); Serial.println(analogRead(A0)); // a little delay to not hog serial monitor delay(100); }