How to change Arduino nano 33 ble sense pwm frequency？

Official Hardware Nano Family Nano 33 BLE Sense
1

The analogWrite frequency of nano 33 ble sense is 500HZ.However，I need 330HZ.
How can I change the pwm frequency?
I have noticed that by using <Servo.h>，we can change servos’ pos from 0 to 180.That means <Servo.h> can change pwm frequency less than 500Hz.
Thanks!

2

Hi @jaxdgskvemvemx. You can do this using the Mbed OS API:

https://os.mbed.com/docs/mbed-os/v6.15/apis/pwmout.html

The core library for the Arduino Nano 33 BLE Sense is built on Mbed OS, so you have all its API available for use in your sketches.

3

Thanks for your reply！I will read it carefully！Thanks！

4

You are welcome. Please let us know if you run into any problems.

I usually am satisfied with the standard Arduino API, but I did play around with PwmOut a couple of years ago. This is a sketch I wrote at that time using Mbed OS to set the PWM frequency to 500 kHz and duty cycle to 50%.

const byte PWMPin = 5; // Arduino pin number
const unsigned int PWMPeriod = 2; // us (minimum value is 2)
const float PWMDutyCycle = 0.5; // ratio

void setup() {
  // set up the pwm object for PWMPin
  mbed::PwmOut* pwm = new mbed::PwmOut(digitalPinToPinName(PWMPin));
  digitalPinToPwmObj(PWMPin) = pwm;

  // set the PWM period to PWMPeriod
  pwm->period_us(PWMPeriod);

  // start the PWM signal with the duty cycle set to PWMDutyCycle
  pwm->write(PWMDutyCycle);
}

void loop() {}