code: func (r *Adaptor) DigitalWrite(pin string, val byte) (err error) {
  	sysfsPin, err := r.DigitalPin(pin, sysfs.OUT)
  	if err != nil {
  		return err
  	}
  	return sysfsPin.Write(int(val))
  }
docs: // DigitalWrite writes digital value to specified pin