proj_lab03b 疑问

  // initialize the frequency of execution monitoring module
  femHandle = FEM_init(&fem,sizeof(fem));
  FEM_setParams(femHandle,
                USER_SYSTEM_FREQ_MHz * 1000000.0,                  // timer frequency, Hz
                (uint32_t)USER_SYSTEM_FREQ_MHz * 1000000,          // timer period, cnts
                USER_CTRL_FREQ_Hz,                                 // set point frequency, Hz
                1000.0);                                           // max frequency error, Hz

  // initialize the CPU usage module
  cpu_usageHandle = CPU_USAGE_init(&cpu_usage,sizeof(cpu_usage));
  CPU_USAGE_setParams(cpu_usageHandle,
                     (uint32_t)USER_SYSTEM_FREQ_MHz * 1000000,     // timer period, cnts
                     (uint32_t)USER_ISR_FREQ_Hz);                  // average over 1 second of ISRs

 这两个函数 在系统中有什么作用？