About Robin7331

Robin7331 · 2021-04-07

Hello guys :waving_hand:I am having a STM32F401CDU6TR on a custom board and I am not able to run it at 84 MHz SYSCLK. The source is an external 8 MHz crystal with two 22pF caps as seen here:I created the project in CubeMX as a Makefile project. I o...

Robin7331 · 2021-04-07

Your right. Thanks for that.It initially was on scale 2 but as I was desperate so I tried many things. Including a different voltage scale :grinning_face_with_sweat:

Robin7331 · 2021-04-07

Absolutely. But it had another problem as well. USB DFU was not working. And sometimes BOOT0 = HIGH was not recognized and it would boot right into flash instead of using the integrated bootloader. All those problems: vanished 朗✌�?And it makes sense ...

Robin7331 · 2021-04-07

Guys. It works! :party_popper: The problem was that I took the wrong cap value for VCAP.I took 2.2nF instead of 4.7uF.Now, there is no problem anymore with having a SYSCLK of 84 MHz. Thanks for the heads up @Community member You made my day :waving_...

Robin7331 · 2021-04-07

Well here's another measurement. Looks a lot better I guess :)Will test if the MCU boots in about an hour. But thanks so far!

Robin7331 · 2021-04-07

Oh you are right! Thats clearly a bug. Thanks for pointing it out. Will swap that for a 4.7uF one.

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Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)

Re: Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)

Re: Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)

Re: Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)

Re: Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)

Re: Unable to run STM32F401 at 84 MHz Sysclk (works fine at 48 MHz)