ECC Error on Read While Write

[tgc-yilmaz]

Hello,

When Read While Write to a specific memory section by using MPC5674F, ECC error occurs and software cannot be run any more. The situation can be solved with soft reset, but this does not always be useful. At the same time, this situation can be corrected by clearing the specified memory section, but I must not lose that data. So, I need another solution for this, can you help with this?

Thank you for your help...

[davidtosenovjan]

Hi, I don't understand your issue too much. It would be fine if you share more details.

However you may seen following appnote dealing with ECC:

https://community.nxp.com/docs/DOC-103300 

[tgc-yilmaz]

I am using MPC56F4F and I want to both read and write to a specific area of the flash at the same time. However, I get an ECC error during this process and I cannot run the program again. Do you have an idea that can fix the error?

[davidtosenovjan]

RWW is only allowed within different partitions. It means if partition being read/executed is 'x', programmed partition must be not 'x'. Do you have it so? And do you have programmed block erased before programming?

[tgc-yilmaz]

Thank you for your answer...

I have programmed block erased before programming. But I'm trying to do this for the same partitions, that's why I get this error.
Well, I understand from your answer, "While the writing process is going on for the same partitions, reading can not be done, so this is not possible."

I have a few more questions for you:

• Is this correct, is there no way to do this, so can we not read while the writing process is going on for the same partitions?

• Is there a way to prevent the reading process to avoid making mistakes while writing for the same partitions? Even if I receive the request to read, can I not respond to this request and prevent an error?

• If we can not prevent this situation, how can we keep the program running when an error occurs? (I get this error in my work and I can't run the program again. Unfortunately, reading request can come while writing is in progress. this is not under my control. I need to solve this problem, somehow I have to keep the program executable.)

[davidtosenovjan]

    Is this correct, is there no way to do this, so can we not read while the writing process is going on for the same partitions?
- Yes, correct.
 

    Is there a way to prevent the reading process to avoid making mistakes while writing for the same partitions? Even if I receive the request to read, can I not respond to this request and prevent an error?
-  Such attempt will cause bus error (leading in core exception) and in the flash controller RWW error is set and operation is stopped.

    If we can not prevent this situation, how can we keep the program running when an error occurs? (I get this error in my work and I can't run the program again. Unfortunately, reading request can come while writing is in progress. this is not under my control. I need to solve this problem, somehow I have to keep the program executable.)
- It is needed to avoid RWW error. The simple solution is to execute code from SRAM. Or you can have certain area dedicated to user flash programming and just to have SW written the way it does not access the area when it is being programmed or erased. It is basically up to you.