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  • Unbrick or fix NAND on the MK808

    OK so on the ug802 there are pads you can short to erased NAND and put the unit into MASK ROM mode. You do this as the ug802 does not have a button to put you in flash mode. But also MASK ROM mode is a special mode unlike flash mode. It erases NAND like it was a brand new chip.

    The MK808 has a reset button BUT it will only put it into ROCK Loader mode (flash mode). The only way to get it into MASK ROM mode it so short 2 NAND pins (like what the UG802 short pads do). I wish the MK808 had these pads to short but they do not.

    Now you might ask "Bob, why would I want to put the unit in MASK ROM mode?". Good question!
    If NAND gets corrupted or you flash another ROM with a loader not made for it, it can screw up NAND and from that point on you will get erased IDB problems, it wont flash properly and give errors, or a host of ROM flashing issues. The ONLY way to fix this is to put it into MASK ROM mode.

    So because Freaktab user natxito is having this problem I figured I would help. I took my unit apart and pulled off the heatsink over the NAND memory chip. I had to do this so I could see where pin 1 was and what the chip part number is so I could look up the spec sheet.
    NAND is H27UCG8T2ATR. I could not find this datasheet but this chip map is the same:

    http://www.hynix.com/datasheet/pdf/f...es(Rev1.1).pdf

    TECHNICAL: On most NAND chips by shorting pins RB and R/E together or in some cases RE and CE, it makes the processor boot up and think there is no NAND memory and puts it into MASK ROM MODE. It also "may" erase NAND.

    OK so here is a text explaination of how to do it. Later I may do a video if I have time.

    On the MK808 pry the cover off at the HDMI port. It helps to plug in a HDMI cable partially into the connector. Then use a screw driver to lift up the lid. The lid is the thinner of the 2 covers. Slowly pry around the edges of the case as you pull the snaps and remove the covers.
    NOW be careful! There are 2 antenna's. One on each side of the case with short wires. So go easy and try not to damage the wires or antennas.

    Once the have it apart the NAND chip is on the side of the board that DOES NOT have the USB etc connectors soldered to it. The chip is under the heatsink and the closest chip to the HDMI connector. If your holding the board with the HDMI connector at the top, pin one of this NAND chip is in the upper left corner of the board.

    Now you can try to pry off the heatsink if you like. It is pretty easy as it is just taped on with heatsink tape. However if you screw up the tape doing so, you will have to go to an electronics store and by more. Clean off the old and install new tape. THIS IS NOT REGULAR TAPE! It has to be heatsink tape.

    If you want to try this without removing the heatsink you still can do it.
    1) Start up my ROM flash tool from my ROM kit. NOTE: you must already have the drivers installed etc or this WILL NOT WORK!
    2) Hook up the USB cable to the OTG port of the MK808. Its the side port not the rear port.
    3) Look between the heatsink and the board and you can see all the pins of the NAND chip. Again pin 1 is at the top. Count down to pins 8 & 9.
    4) With a needle or a pin put the pin between pins 8 and 9 and hold it there. You are trying to short these 2 pins so make sure your actually on them.
    5) No plug in the USB cable to your PC to power on the unit.
    6) If you are shorting the pins the PC should bong and the flash tool should say at the bottom "Found RKAndroid MaskRom Rock USB". If not, then your not shorting the pins properly OR you never had the drivers loaded to begin with.
    7) Good! If you have MASK ROM mode then now erase NAND (IDB). Let it finish.
    8) Flash the ROM. YOu must have the loader check box checked or it will complain and tell you a loader must be flashed.

    Thats it! You should be unbricked and hopefully your ROM flash problems should be gone. If not, you can try to repeat the proceedure but if you still have issues, alas, you may have a failed NAND chip.

    Bob



    Attached Files
    "Pzebacz im, bo nie wiedzą, co czynią"
    "Прости им, они не ведают, что творят"
    "Perdona loro perché non sanno quello che fanno"
    "Vergib ihnen, denn sie wissen nicht, was sie tun"
    "Vergeef hen want ze weten niet wat ze doen"
    "Pardonne-leur car ils ne savent pas ce qu'ils font"
    "Perdónalos porque no saben que lo que hacen"
    "Oprosti im, jer ne znaju što čine"
    "Forgive them as they know not what they do"






  • #2


    Thanx for sharing your knowledge and for all the effort you are putting into this.

    Without people like you this "scene" would not be possible.

    Comment


    • #3
      Hey,

      Thanks for your trick, i just receveid my mk yesterday, and trying to flash with finless rom; but after while all gone corrupted and i tried this one and the mk is still alive

      Thanks for all

      Comment


      • #4
        Thanks for your help.

        I think all of us appreciate your efforts and work.

        Jose Ignacio.

        Comment


        • #5
          Errorownload IDB failed

          EDIT: Issue resolved - Plugging the device into another USB port at my PC turned the trick. Flashing the new ROM then worked like a charm at first try.

          Hi Bob,

          thank you very much for providing instructions on how to unbrick the MK808.

          Unfortunately, they don't seem to work for me - at least not completely. I keep getting error messages
          Error: Download IDB failed
          ERROR: Run failed

          I have opened the box, have short-circuited pins 8 and 9 of the NAND chip, then connected the box to the PC using the OTG port.
          Your ROM Flash Tool detects the MK808 in Mask ROM mode and Erase NAND works fine. It's flashing the ROM that fails for me.

          Output in the status window reads like this:
          INFO: Start to erase NAND
          INFO: Erasing IDB OK
          INFO: Start to run
          INFO: Start to download boot
          INFO: Download boot OK
          INFO: Start to test device
          INFO: Test device OK
          INFO: Start to download IDB
          Error: Download IDB failed
          ERROR: Run failed

          I'm attaching the log file for more detail.

          I'd appreciate if you could take a look and provide some guidance. For how long is the short-circuit supposed to be maintained? Just until the driver has loaded and the Flash Tool has detected the device or throughout the NAND erase process or through the complete Flash process?

          Thank you very much.
          E_Zatopek
          Attached Files
          Last edited by E_Zatopek; 11-12-2012, 01:04. Reason: Issue resolved

          Comment


          • #6
            I think all of us appreciate your efforts and work.
            Remember what should be remembered, and forget what should be forgotten. Alter what is changeable, and accept what is mutable.

            Comment


            • #7
              thank you

              i had the original firmware and read about your rom that was excellent and decided to flash it, but the 1.5a bricked my device after first reboot (i suppose that this thing is related to the liberation of new space for apps in the nand), i tried to do A LOT of things but it seems that despite mostly in all the times, all those firmware flashed fine, when i booted the device went crazy and stop working and do a lot of crazy things... so after this new method my device was fixed, for that THANK YOU!, now... i dont want that this happen again so.. do you advice me that from now i will stick with your firmware updates and use your tool instead of the rockchip batch tools and their firmwares? because the normal rockchip firmwares has a different file system that might corrupt the filesystem that 1.5a creates (i believe)...

              and could i flash my nand by the mask rom method and after of this could flash with the rockchip batch tool?

              thank you

              Comment


              • #8
                Yes the BathTool also recogonizes MASK ROM mode. The box in the batctool is a different color than green in that mode.. As I recall it is red.

                Bob
                "Pzebacz im, bo nie wiedzą, co czynią"
                "Прости им, они не ведают, что творят"
                "Perdona loro perché non sanno quello che fanno"
                "Vergib ihnen, denn sie wissen nicht, was sie tun"
                "Vergeef hen want ze weten niet wat ze doen"
                "Pardonne-leur car ils ne savent pas ce qu'ils font"
                "Perdónalos porque no saben que lo que hacen"
                "Oprosti im, jer ne znaju što čine"
                "Forgive them as they know not what they do"





                Comment


                • #9
                  ugh...

                  EDIT: OKAY... SO, here is what I have done that I "think" may have fixed it as it appears to be flashing now... I went into the NEW Rockbatch tool and used the "upgrade" option to flash. It appears to be flashing normally now. Will know in a few minutes...

                  EDIT2: Helpful tip... I did this with the Heatsink ON as I really didn't feel like making a trip to Radio Shack for heat-sink tape. It was tricking to see though and I was using a needle that is reflective making it even MORE tricking to see. Here is an easy way to figure out where to stick your pin, if you notice in the close up picture, look at the line of copper going around the outside... there is a small "box" outcropping (in cropping?) protruding in towards the NAND chip. If you put your pin straight on and slightly to the left of that you will hit between pins 8 & 9 every time.

                  Get all the way through the steps, erase the IDB, but when i go to flash a new rom it fails to download the IDB...?

                  Not sure why?

                  If I leave the pin in place the whole time it will fail. If I take the pin out before flashing then it just hangs on "start to download IDB" ?

                  Any idea? I wasn't sure how long to keep the pin in place.

                  Thanks for your help and kind regards,

                  Roman

                  PSS I have tried different USB ports per the other posters comments... still not going...


                  BTW - Big thanks! Where else in the world would anyone find this information?!

                  Comment


                  • #10
                    I do not know if the RKbatch tool can be used in this way. The RK Android tool can. It has to say MASK rom mode at the bottom when you do the pin short thing. If you have drivers installed for RKBatch tool then RKAndroid tool should also work as it is the same drivers.

                    Bob
                    "Pzebacz im, bo nie wiedzą, co czynią"
                    "Прости им, они не ведают, что творят"
                    "Perdona loro perché non sanno quello che fanno"
                    "Vergib ihnen, denn sie wissen nicht, was sie tun"
                    "Vergeef hen want ze weten niet wat ze doen"
                    "Pardonne-leur car ils ne savent pas ce qu'ils font"
                    "Perdónalos porque no saben que lo que hacen"
                    "Oprosti im, jer ne znaju što čine"
                    "Forgive them as they know not what they do"





                    Comment


                    • #11
                      Originally posted by Finless View Post
                      I do not know if the RKbatch tool can be used in this way. The RK Android tool can. It has to say MASK rom mode at the bottom when you do the pin short thing. If you have drivers installed for RKBatch tool then RKAndroid tool should also work as it is the same drivers.

                      Bob

                      There is no option to clear IDB in RKbatch, however RKBatch does recognize the MK808 in this mode as it gives a "blue" square instead of the green (firmware update mode), flashing yellow (update in process), red (failure), or purple (device powered on and android booted and connected to USB mode). So it definitely sees this mode as something different. It allows you to start a firmware update process....

                      Now onto the next ridiculous hurdle. I have 4 M3 tablets here and 1 of them absolutely refuses to go into firmware update mode . Meh... Going to try you tool to see if it can reboot the device.

                      Regards,

                      Roman


                      UPDATE: THANKS THANKS AND THANKS! The older flash tool you use actually got this bloody device to go into firmware update mode. The other 3 M3's I had worked with no problem using the button combination but I had this one unit that just absolutely wouldn't do it. Your "reboot to flash mode" button really saved my hide .

                      UPDATE 2: Meh... it flashed normally and THEN once it was done, it refused to reboot. Now it appears to be totally dead. This is so odd, I have never had any rk3066 device give me problems like this until this M3.... sigh....

                      UPDATE 3: Apparently it was still in firmware update mode (this is getting odder and odder) as I just plugged it back in and it was recognized in both tools. I am attempting to flash again. Perhaps I will need to use the "upgrade option again in the one tool or maybe erase the IDB first?

                      Regards,

                      Roman

                      Comment


                      • #12
                        It rebooted to flash mode because it could not load recovery.img. So that was a bad flash. YES erase IDB always when trying to recovery from a brick.

                        Bob
                        "Pzebacz im, bo nie wiedzą, co czynią"
                        "Прости им, они не ведают, что творят"
                        "Perdona loro perché non sanno quello che fanno"
                        "Vergib ihnen, denn sie wissen nicht, was sie tun"
                        "Vergeef hen want ze weten niet wat ze doen"
                        "Pardonne-leur car ils ne savent pas ce qu'ils font"
                        "Perdónalos porque no saben que lo que hacen"
                        "Oprosti im, jer ne znaju što čine"
                        "Forgive them as they know not what they do"





                        Comment


                        • #13
                          Originally posted by Finless View Post
                          It rebooted to flash mode because it could not load recovery.img. So that was a bad flash. YES erase IDB always when trying to recovery from a brick.

                          Bob
                          I am starting to think my supplier screwed up and sent me one unit using the older PCBA motherboard (idiots). That is really the only explanation for the really odd behaviour.

                          -Roman

                          Comment


                          • #14
                            Rom Flash tool

                            Where can I find this rom flash tool?

                            Can you please provide a link?

                            Does this involve the drivers?

                            Thanks

                            Comment


                            • #15
                              You are the bomb finless!!

                              I am seriously thinking about starting up the finless fan club! lol. All joking aside I just want to say thank you so much for this fix! Im kinda of a tech savy guy but chances are I would have never come up with this on my own. I got my mk808 less than a week ago and my intentions for geting it were to have something inexpensive to tweek and hack on, so thats what ive been doing. I was trying some methods to get JB 4.2 running on my 808 but the only thing I suceeded at was severly bricking the little guy. Wouldn't turn on, wouldn't re-install any firmware wouldn't do anything other than raise my blood pressure.I have to tell you I thought my little android gadget that ive grown to love so quickly was done for good! So I came accross your little trick and it certainly saved the day. It also saved me 65 bucks that I would have spent on another if this one was dead. Not to mention the month or two it takes to get to the USA from China. Thanks Finless Bob!

                              Comment

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