pwm on Wio Terminal

#include "Adafruit_ZeroTimer.h"

// Adafruit Zerotimer library uses A5(PB9) as waveform output for TC4 Channel 1
// Wio Terminal uses D1

// This can be seen here:
// https://github.com/Seeed-Studio/ArduinoCore-samd/blob/bcc92a8edfd324989e41080bb3521ddfbee4dc2e/variants/wio_terminal/variant.cpp#L31


// So need to replace A5 with D1 here:
// https://github.com/adafruit/Adafruit_ZeroTimer/blob/e8e9eb3556326eea3ff3a28266d578c971d2d4d0/Adafruit_ZeroTimer.cpp#L337   



Adafruit_ZeroTimer zt4 = Adafruit_ZeroTimer(4);

void setup() {
  Serial.begin(115200);

  //delay(10000);
  pinMode(D1, OUTPUT);
  zt4.enable(false);
  zt4.configure(TC_CLOCK_PRESCALER_DIV1, // prescaler
                TC_COUNTER_SIZE_16BIT,   // bit width of timer/counter
                TC_WAVE_GENERATION_MATCH_PWM // frequency or PWM mode
                );

                
  if (! zt4.PWMout(true, 1, D1)) {
    Serial.println("Failed to configure PWM output");
  }

  else {
    Serial.println("PWM output configured");
      
  }

  // 10kHz 50% duty cycle square wave
  zt4.setPeriodMatch(4799, 4799/2, 1);
  zt4.enable(true);
}

void loop() {


}