TIM6 APB1 prescaler

Mykola_Levun · ‎2024-08-23

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).

SofLit · ‎2024-08-23

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.

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SofLit · ‎2024-08-23

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

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Mykola_Levun · ‎2024-08-23

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

SofLit · ‎2024-08-23

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

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Mykola_Levun · ‎2024-08-23

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

SofLit · ‎2024-08-23

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.

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.
PS: This is NOT an online support (https://ols.st.com) but a collaborative space. So please be polite in your reply. Otherwise, it will be reported as inappropriate and you will be permanently blacklisted from my help/support.

Mykola_Levun · ‎2024-08-28

Hello,

Thanks for the explanation, I understood everything.