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cannot change data flash on BQ20Z95 GUI

Dear all,

sorry if this has been answered before, I can't seem to find the answer.
I'm trying to change a dataflash parameter on a BQ20z95 board I once used for a different purpose.

I verified that it is unsealed (I wrote the unseal command and the parameter are not greyed),

and I wrote the full access mode words (ffff ffff), to make sure I have full access.

when I write 0x60, I read (FFFF FFFF), so it means it is not locked, right?

still I get this result when I try to change a parameter. why is that?

best regards,

  • Was there an attachment/picture as i do not see it so I am unclear what result you refer to or what you are trying to do.

    Are the SS and FAS bits set when you power on or do a  reset (0x41) ?.

     

    What are you trying to do?

     

  • Dear Mike,

    I attached a picture, that was removed from my original post.

    I'm trying, for example, to change PUV threshold parameter.

    SS & FAS bits are 0. I sent RESET(0x0041), and it didn't help.

    and I tried with with 2 different PCBs.

    the PCB manufacturer confirmed that he did not lock the unit and it is approved to change any parameter.

    any idea?

  • can you attach a screen shot of the SBS screen so I can you have no permanent fail flags set. This would  prevent writing to FLASH and so you would need to clear them first. Also check pack voltage as that could be an issue to if it is too low.

    thanks

    Mike

  • Dear Mike,

    thanks for your assistance,

    no permanent fails, I can only see a CUV/PUV that occurs since the battery was programmed as 3S initially.

    I already calibrated the pack to be 2 cells in the calibration tab.

    any ideas?

  • Hi Ran,

    One thought - I see your pack voltage is 7256mV and am wondering what value you have programmed for "FLASH Update OK Voltage". According to the TRM sect C.9.1.1 the default value is 7500mV and below this voltage no FLASH update is allowed.

    Have you tried using bqeasy to load in a fresh senc and start again if this board has already been used just to get rid of any old settings ? Are you attached to real cells at the moment or using power supplies and resistors to simulate 2 cells. If so try increasing the pack voltage or if using batteries charge up the cells a bit. At this point maybe being attached to a power supply and resistors would make things a bit easier.

    Mike

     

     

  • Dear Mike,

    lading a fresh senc file did not work, since your first remark was accurate.

    once I charge the battery pack over 7500mV, I was able to change everything again.

    thank you very much!

  • hi Rian,

    your first problem as you wrote is that you cant change the DATA Flash constants, plz write in WRITE TO WORD COMMAND 2673  1712 and then press refresh

    then go to the data flash and change as you want the constants,


    secondly is your battery is 3 cell in series?

    if you have any questions you can contacts on laptotech@yahoo.com

    thx

  • Dear Zultan,

    thanks for you assistance,

    resting the PF flags (using WORD command) won't work, if the minimum voltage for flash is not met.

    it worked when I let the battery to be charged over 7.5V.

    Battery is 2 cells in series. and problem is fixed when you write it in calibration screen.

    thanks again.

  • Dear,

    I am unable to rewrite the constraints in data flash although SS and FAS flags and clear. Also i tried the 2 word command of 2673 1712 but problem still occurs.
    Kindly revert ASAP.
  • Hi Deepak,
    I responded to you earlier about FAS and SS on another post this morning, did you read my response, did it help , please close that if it did?
    It is really hard to help you efficiently if you keep jumping around posting on the end of old threads even ig they may seem related, please create a new issue for your problems so we can keep track of problem , what we tried to fix , progress etc .
    I assume from this thread you did manage to unseal and get full access now ? So why do you now send the PF clear key , do you have PF flags set? Can you post a picture of the PC screen looking at EVSW SBS window so I can see what you see ?
    What voltage do you have at top of cell stack and is it more than the "FLASH UPDATE OK VOLTAGE" which by default comes programmed as 7500. If you have less than 7500mV you cannot program the flash. You will need to raise the voltage applied to chip.
    Mike