docs: public void setAlwaysOn(Pin pin) {
          final int pwmOnValue = 0x1000;
          final int pwmOffValue = 0x0000;
          validatePin(pin, pwmOnValue, pwmOffValue);
          final int channel = pin.getAddress();
          try {
              device.write(PCA9685A_LED0_ON_L + 4 * channel, (byte) 0x00);
              device.write(PCA9685A_LED0_ON_H + 4 * channel, (byte) 0x10); // set bit 4 to high
              device.write(PCA9685A_LED0_OFF_L + 4 * channel, (byte) 0x00);
              device.write(PCA9685A_LED0_OFF_H + 4 * channel, (byte) 0x00);
          } catch (IOException e) {
              throw new RuntimeException("Error while trying to set channel [" + channel + "] always ON.", e);
          }
          cachePinValues(pin, pwmOnValue, pwmOffValue);
      }