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Associate
Jul 15, 2023 8:53 AM UTC
Question

STM32WB55 external clocks(32.768KHz, 38MHz) not working

Hello All

I have a cutom board. I am working on STM32WB55VGQ6(BGA129).
2 crystals(32.768KHz, 38MHz) output waves are not coming.
I checked waveform by using an oscilloscope and OSC-IN/OUT pins are ground level(0V)
Voltage conditions all 3.3V : VDD, VDDUSB, VDDRF, VDDA, VDDSMPS
Crystal part# : FW384WFIN1, AGS05-32.768KHZ-6T
Expers please help me.

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17 replies

AScha.3
Super User
Jul 15, 2023 9:00 AM UTC

did you set the lse+hse in Cube ?  and flash this program then ?

AScha3_0-1689411608703.png

otherwise cpu running on internal clock only.

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Associate
Jul 15, 2023 12:29 PM UTC

Hi AScha.3
Thank you for response.
I'd tried connect to my board with STM32cube but STM32cube can not access my board.

AScha.3
Super User
Jul 16, 2023 1:39 PM UTC

so this is first problem, you have to care about.

without loading a program - no external clocks running.

+ connect with...stlinkV2 ? or how to..? and boot pin at gnd ? or try bootloader ?

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KKIM.6
Senior
Jul 15, 2023 10:10 AM UTC

I'm using WB55 but WB55 use 32 MHz, Not 38 MHz. you need to check spec whether 38 MHz is correct.

You can check whether clock is correctly implanted to microcontroller following this example that company provided.

https://www.youtube.com/watch?v=qNJR9vL1D0c

Associate
Jul 15, 2023 12:24 PM UTC

Hi KKIM
Thank you for fast response.
STM32WB55 supports 64MHz.
I'd changed 16MHz OSC it still not working

MM..1
Super User
Jul 15, 2023 2:18 PM UTC

StLink pinout? What is your cube ? IDE or Programmer sw?

Associate
Jul 17, 2023 1:15 AM UTC

Hi MM

Thank you for response.

I'm using STM32CubeIDE(ver 1.13) and microUSB 5pin cable, not use STlink.

MM..1
Super User
Jul 17, 2023 4:26 PM UTC

Your choiced bootloader load isnt native suppoerted in IDE. You need handle load sw manualy or over script. Too you cant debug with this setup. Why you choice this?

MM1_0-1689611158158.png

 

Associate
Jul 20, 2023 1:40 AM UTC

Hi MM

Thanks a lot for your help.
I'll take a good look at the document you said.