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eBirdman
Senior
April 26, 2026
Question

STM32H743 - Setting External Event source for HRTIM Timer in CubeMX ?

  • April 26, 2026
  • 2 replies
  • 83 views

There are 4 external events that can be chosen to trigger and reset individual counters of each HRTIM timer unit in STM32H743 MCU. CubeMX shows those events once the Event Configuration is chosen "Enabled" . Yet only Source 1 is active (allowed to be chosen) but the Source 3 that I need to connect internally to the TIM2 TRGO output is inactive (cannot be chosen) . Why? My attempts to use AI got strange results - after searching the STM documents AI concluded that CubeMX is limited , it allows only external on-pin connections and any internal connections must be manually coded in addition to the generated code. 

If it is so then why does CubeMX show those other options yet does not allow to choose them? Or is there way to activate those options ?

Please anybody give me suggestion.

Note: the STM32CubeMX is the latest downloaded and installed yesterday. The MCU library pack is also current.

eBirdman_0-1777170134029.png

 

2 replies

mƎALLEm
Technical Moderator
April 27, 2026

Hello,

I did the exercise and I can see TIM2 TRGO is not grayed out for HRTIM external event 2 source:

mALLEm_0-1777286076469.png

and can be selectable:

mALLEm_1-1777286107063.png

What MCU part number you've set in CubeMx?

I've attached my ioc file.

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eBirdman
eBirdmanAuthor
Senior
April 27, 2026

Thank you for  giving me hope but I am yet to repeat this in my configuration. My MCU package is STM32H743VITx (100 pins package) . TIM2 TRGO enabled and configured but still greyed out as a choice for HRTIM... I'll try to compare the .ioc files, will try to pinpoint the difference... 

Is your CubeMX the latest v.6.17.0 ?

April 27, 2026

thanks for this....