What is the best way and safer way to make one led blinked and, at the same time, control one motor?

STM32 has the capability to perform checksum self checking.If no, there is some way to verify that the program have been loaded properly.

I would like to create a kind of calendar with one STM32 MC. When the application will advise me to do scheduled activities. I was thinking to use timer interrupt and I would like to know if there is a quantity limitation of timer interrupt per STM32...