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STM32F4 Bootloader Version

Associate II


We have Custom Board Build Around STM32F4 Micro Controller in one of the Micro Controller Boot-loader Version is 0x91 Available to do Flashing and All but in Other Board Boot-loader Version is 0xFF and Not Available to do Flash, Anybody Know About this And what Exactly Issue is there So kindly Share your Points on this.


Thank You 


ST Employee

Although you have indicated that you are using something from the STM32F4 family, you have not specified the exact type. The bootloader ID 0x91 is contained in several variants:

  • STM32F40xxx
  • STM32F41xxx
  • STM32F42xxx
  • STM32F43xxx

However, if you only read 0xFF instead of 0x91, it is very likely to be a fake STM32.

If you have the label from the packaging, you are welcome to send me the bulk ID by PM (not publicly here, because it can be misused) and I will then check whether they are original parts. If you don't have the bulk ID, you'll have to contact the dealer to prove the origin of the STM32F4.

Hope that helps?


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