TIM6 APB1 prescaler

[Mykola_Levun]

Hello,

STM32F103RB microcontroller.
The Figure1 (see attached image) shows clock tree of STM32F103RB microcontroller. Before TIM6CLK, there is a block, which is highlighted in red rectangle. What's IF (APB1 PRESCALER  = 1) x1 ELSE x2 label in this red rectangle? APB1 prescaler can't equal to  "1". APB1 prescaler can be in states listed in the Figure2 (see attached image).

[mƎALLEm]

APB1 PRESCALER  = 1 ->  "Not divided" which is the first value (0xx).

[Mykola_Levun]

Why is this (IF (APB1 PRESCALER  = 1) x1 ELSE x2)  shown so strangely in the clock tree diagram?

[mƎALLEm]

Do you mean APB1 PRESCALER needs to be = 0 in the clock tree?

[Mykola_Levun]

I mean, why is APB1 PRESCALER  = 1 the same as "Not divided" which is the first value (0xx)?

[mƎALLEm · Accepted solution]

Sorry, didn't understand ..

Value divided by 1 = Value so it's not divided. A clock divided by 1 keeps the same frequency on the output prescaler -> frequency not divided.

[Mykola_Levun]

Hello,

Thanks for the explanation, I understood everything.