TIM2 autostart ADC1 (Scan, 4 channel) w/o HAL_ADC_Start_DMA() ?

[PRenn.1]

I'm searching for super coding comfort in CubeIDE.   Currently TIM2 resets/updates.
In HAL_TIM_PeriodElapsedCallback()  I "manually" start HAL_ADC_Start_DMA() the Scan conversion of four channels and have the four results shipped into my progs memory, via DMA.   Works like a charm.

But there is the mighty diagram  (Fig.31) on p.213 of the STM32F411CEU6  reference manual, 
clearly showing that ther are alternatives to starting the ADC manually via software.  
Among a lot of options there is TIM2_TRGO or TIM2_CHx configurable as ADC trigger input.

So,  is the following possible:
1) TIM2 loops indefinitely at a speed configured by me after being started once in main().
2) At every interation TIM2 triggers the start of  the ADC (HOW?).
3) The ADC is configured to convert 4 channels.
4) The ADC is configuired to ship the result of every conversion to my memory via DMA.

Currently I've no idea how to click / dropdwon  CubeIDE to get 2)  working.

The result would be very cool:
no callbacks at all,  all steps in that process chain done automagically,
the software coder simply has to look at DMA destination buffers, and do his thing.

[MasterT]

Check it out:

https://github.com/STMicroelectronics/STM32CubeF4/tree/master/Projects/STM32F411RE-Nucleo/Examples_LL/ADC

https://github.com/STMicroelectronics/STM32CubeF4/tree/master/Projects/STM32F411RE-Nucleo/Examples_LL/ADC 

[PRenn.1]

Nice examples, thx!

I found TIM2 settings :

/* Set timer the trigger output (TRGO) */
LL_TIM_SetTriggerOutput(TIM2, LL_TIM_TRGO_UPDATE);
/* Enable counter */
LL_TIM_EnableCounter(TIM2);

sounds familiar, but directly via the LowLevel interface routines.  TIM2_TRGO UPDATE is set.

There are ADC Setting, too:
/* Set ADC group regular trigger source */
LL_ADC_REG_SetTriggerSource(ADC1, LL_ADC_REG_TRIG_EXT_TIM2_TRGO);

So the TIM2 Output is set to TRGO_UPDATE and the ADC is set to have TIM2_TRGO as trigger source.
=> Exaclty what I tried in CubeIDE (CubeMX confgiured, I think) but no data delivered.

Question is what / where to click in CubeIDE HAL-config to setup both
TIM2_TRGO_UPDATE and ADC trigger_source TIM2_TRGO 

[MasterT]

There is no such option like set both. I even can't find to set TIM2_TRGO in the timer's sub-menu tabs. Regarding setting linked two lines timer-trgo And adc-trigger, feature wouldn't make sense if more than one timer has active trigger line or many adc linked to different triggers, so this  linkage delegated to programmer, to set it "manually".

[PRenn.1]

There are only three HAL_ADC_Start routines:  polling, IT (Interrupt) and DMA. 
Somehow I'm missing "HAL_ADC_Start_trigger"   or "HAL_ADC_Start_TIM2TRGO" .

If I comment out the HAL_ADC_Start_DMA in the TIM2 interrupt routine, and only do one single HAL_ADC_Start_DMA right befor the "main loop" 
I get  exactly one setup of conversions, and nothing exlse although the TIM2 happily counter and overflows etc

[CactusPete]

I'm in a similar situation. H7 family should be able to start DMA transfer via synch signal and emit an event (not software start), but nobody at STM seems to understand either our questions or the chips are now too complex for STM to figure out how to use.