code: public static byte[] setDisplayClock(byte divideRatio, byte oscillatorFrequency) {
          if (divideRatio < 0 || oscillatorFrequency < 0) {
              throw new IllegalArgumentException("Divide ratio and oscillator frequency must be non-negative.");
          }
          byte param = (byte) ((oscillatorFrequency << 4) & divideRatio);
          return new byte[]{COMMAND_CONTROL_BYTE, SET_DISPLAY_CLOCK, COMMAND_CONTROL_BYTE, param};
      }
docs: timing configuration commands