Timers: Slave mode disabled and trigger source set to ITR0 when CK source is internal. What happens?

[ubaldot]

I am studying STM32 timers (I have a Nucleo F446re) and I am wondering what is a use-case for this configuration

Slave Mode: Disabled

Trigger Source: ITR0

Clock Source: Internal

In my understanding you use ITRx when you want to cascade timers (i.g. TGRO of a timer is connected to a ITRx of another timer) but I wonder what happens in this case, in particular when there a rising edge is detected in ITR0? 

[Sarra.S]

Hello @ubaldot, 

This can be used for synchronization purpose, even though the timer is not in a slave mode, the ITR0 trigger can be used to synchronize the start of the timer with another timer. For example, you might want the timer to start counting when another timer reaches a certain condition and generates a trigger output (TRGO). 

Also ITRx signals can be used to generate specific events or interrupts within the timer, when a rising edge is detected on ITR0 foe example, it can be used to generate an update event or set a flag that can be used in an ISR 

Hope that helps!