In order to trigger ADC's at a regular interval, TRGO output from a Timer is often used. The currect class definition of the HardwareTimer does not allow this to happen. The easiest way for this is to add a function/method that does something along the lines of
enableTRGO() {
TIM_MasterConfigTypeDef mct;
mct.MasterOutputTrigger = TIM_TRGO_UPDATE;
mct.MasterSlaveMode = TIM_MASTERSLAVEMODE_ENABLE;
HAL_TIMEx_MasterConfigSynchronization(&s_TimerInstance, &mct);
}