void TIMER_1_INST_IRQHandler(void)
{
    switch (DL_TimerA_getPendingInterrupt(TIMER_1_INST)) {
        case DL_TIMERA_IIDX_ZERO:
            DL_TimerA_getTimerCount(COMPARE_0_INST);
            freq = DL_TimerA_getTimerCount(COMPARE_0_INST) + DL_TimerA_getTimerCount(COMPARE_1_INST) * 65536;
            // freq = 999;  /* 測試頻率 */
            // printf("freq = %d Hz\r\n\r\n", freq);
            timer_measure_freq_end_flag = true;
            DL_TimerA_setTimerCount(COMPARE_1_INST, 0);
            DL_TimerA_setTimerCount(COMPARE_0_INST, 0);
            break;
        default:
            break;
    }
}