STMCubeMX V 5.0 TIM6 problem I'm using LL libraries. The interrupt generated with any setting always has a frequency around 3.6 MHz. Thanks for your help.

Well, go to debug mode and look at the timer register values. You can manually adjust them, run and stop the code to find out what maybe wrong. Debug phase. Or compare with a similar LL example coming from the closest stm32 nucleo board.

I have done other applications with STM32F4 64 and 144 pins with STMCube versions prior to V5.0 and everything works fine. I also compared the software but I did not find anything strange. I do not have much practice with debugging now however I will try. Thank you