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STM32H743XI silicon Y - DBGMCU dead ?

Dan4
Associate II

Curious if anyone else encountered this: I work on a design using STM32H743XI silicon Y and DBGMCU seems to be completely dead. Reading any register returns 0 (so no REV_ID/DEV_ID). Writing to get 'timer freeze on debug' does not work either and reading back the written registers returns 0's.

The Errata does not mention anything like that.

I am aware that the Debugger is supposed to see DBGMCU at 0xE00E1000 and the CPU at 0x5C001000, but neither works.

Am I missing something ? - there is no RCC clock enabling for this class of MCUs... ; the ref manual lists DBGMCU->CR bits D1DBGCKEN and D3DBGCKEN, which are not dealt with in the standard HAL, but again trying to set them and re-read, I get back 0's...

Thanks.

22 REPLIES 22
jeremi
Associate II

As I mentioned above, this issue has been fixed in Keil 5.29. LL_DBGMCU_APB1_GRP1_FreezePeriph works for me.

Sorry, I missed your post on the topic. I'm gonna try the latest MDK version.

Simon V.
ST Employee

Hello,

When the debugger is not connected and the clock gating feature is enable, the JTAG clock is automatically stop.

You must configure RCC_CKGAENR register to JTAGCKG clock gating disabled : the clock is always enabled then you can dump correctly REV_ID/DEV_ID @ 0x5C00100 address.

Regards,

Simon

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