#Arduino mega 2560 digital pins pwm how to
#Arduino mega 2560 digital pins pwm code
#Arduino mega 2560 digital pins pwm plus

the time during which the signal is HIGH is called the pulse width.

If we switch the signal between these two values at an extremely fast rate, say, 500 times in 1 second, the signal at the output will appear to be continuous it will seem as if it is an analog signal. The duration of on-time, i.e. A digital signal, in general, can have either of the two values: HIGH/ON or LOW/OFF. Note that timer 0 is the one on which rely all time functions in Arduino: i.e.PWM, or Pulse Width Modulation is a technique for getting an analog output using digital signals. Prescaler = 6 -> PWM frequency is PWM frequency is 31000 Hz Hi guys! After some day, I finally managed to change the PWM frequency of all PWM pins of my Arduino Mega 2560.Īll the explanations are foundamentally here:Īrduino Diecimila and the Atmega168: Changing PWM Frequency on the Arduino Diecimila and the Atmega168 Note that timer 0 is the one on which rely all time functions in Arduino: i.e., if you change this timer, function like delay() or millis() will continue to work but at a different timescale (quicker or slower!!!) Prescaler = 3 -> PWM frequency is 980 Hz (default value) Prescaler = 2 -> PWM frequency is 7800 Hz Prescaler = 6 -> PWM frequency is PWM frequency is 62000 Hz Prescaler = 3 -> PWM frequency is 490 Hz (default value) Prescaler = 2 -> PWM frequency is 4000 Hz Prescaler = 1 -> PWM frequency is 31000 Hz

I registered those values on all PWM pins, changing the value of prescaler (the only exception are pins 13 and 14, see later):

now we have a new PWM frequency on pin 9 and 10!.

TCCR2B |= myPrescaler //this operation (OR), replaces the last three bits in TCCR2B with our new value 011 In this case, 3 corresponds in binary to 011. Int myPrescaler = 3 // this could be a number in.

now that CS02, CS01, CS00 are clear, we write on them a new value:.

#Arduino mega 2560 digital pins pwm plus

TCCR2B &= ~myEraser // this operation (AND plus NOT), set the three bits in TCCR2B to 0 Int myEraser = 7 // this is 111 in binary and is used as an eraser Those bits in fact represent an integer number (from 0 to 7) called 'prescaler', that Arduino uses to generate the frequency for PWM.įirst of all, we have to clear these three bits, i.e they must be all set to 0:

The first three bits (from right to left!) are called CS02, CS01, CS00, and they are the bits we have to change. So, if we want to change the PWM frequency of pins 10 and 9, we will have to act on TCCR2B.

#Arduino mega 2560 digital pins pwm code

You can access a timer simply changing in your code (tipically in the setup()), the value of variable TCCRnB, where 'n' is the number of register. This is the list of timers in Arduino Mega 2560:Īs you can see, a given timer controls more than one pin (every change about a timer will affect all pins depending on it!). In order to change frequency on pin 'A', we have to change some value in the timer Whose frequency is 980 Hz (I checked with an oscilloscope). The PWM default frequency is 490 Hz for all pins, with the exception of pin 13 and 4, Here follows my brief instructions and descriptions!Īrduino 2560 has 12 pins supporting PWM. Here I simply modified a little bit the author'code to make it match with Arduino 2560.

#Arduino mega 2560 digital pins pwm how to

In this brief article the author explains very clearly how to change some values in Arduino Diecimila registers, in order to enhance the PWM frequency.