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L1 data SRAM after software reset through watchdog in BF70x

I have implemented a second stage bootloader and want to use a shared variable in L1 RAM. This variable will be shared with the main application.

Therefore I created a section in both ldf-files with NO_INIT 

      L1_data_b_shared_variable NO_INIT

 and I define the variable

#pragma section ("SHARED_UPDATEVAR", NO_INIT) 
  volatile unsigned char Update_Req;

My software in the main application write to the variable Update_Req and performs an software reset through watchdog like in

Always when my second stage bootloader starts after the watchdog reset and want to read the variable Update_Req in L1 RAM the variable is zero.

So my question is what is the status of L1 SRAM after a watchdog reset?  Does it retain the data it held before the reset or is it indeterminate? 

I implemented the same in the BF534 an it works but not with my BF707.

Best regards,


  • Hi Michael,

    Apologies for delayed response. From your mail, I could understand that you are looking for preserving L1 SRAM after watchdog reset. Please correct if my understanding is wrong.

    I've taken a look at your shared snippet and it seems fine. I also understand that you are performing Second stage loaders. Can you let me know how you are confirming that L1 data is not preserved?

    If possible can you share a minimal project that replicates the issue on ADSP-BF707 Ezkit?

    Anand Selvaraj.

  • Hi Anand,

    yes your understanding is correct. After a watchdog reset my second stage bootloader starts and want to read out data from L1 SRAM.

    For debugging I send the variable in L1 SRAM via a CAN Message. The variable has always the value zero.

    My projekt runs not on the ADSP-BF707 Ezkit but if you think it would be helpful I can share a minimal project. These are two projects , one for the application and on for the second stage bootloader.

    If it's possible i wouldn't like to share the project in the forum, so could you give me a contact or email. Please let me know.

    Regards, Michael  

  • Hi Michael,

    Can you please send a mail to Please refer this thread link while you send the project. A minimal project replicating the issue on ADSP-BF707 EZkit is enough.

    Anand Selvaraj.