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ZTPad Repeated Rebooting, Never Finishes

25K views 62 replies 5 participants last post by  dryster 
#1 ·
Tonight I was using my ZTPad as usual, not doing anything special, and I had it connected to AC at the time. I heard the kind of pop you get when you use the Reset hole. The tablet started rebooting, but it only showed the ZTPad splash screen and never switched to the Android splash. I tried resetting, but when it started again, it behaved the same and never finished booting.

Later on in another attempt, it did get to the Android splash, but then it popped again and rebooted.

Do you have any idea what is wrong and whether it can be corrected?

I bought my ZTPad from Ali Baba in April, so I don't know if there's any warranty left on it.

Lane
 
#2 · (Edited by Moderator)
As a last resort, you can always reflash a ROM onto your tablet to get it working again......

For a "never finishes booting" problem with my tablets, it's usually a dalvik-cache problem, and deleting the contents of the /data/dalvik-cache/ folder via adb while it's trying to boot usually fixes it for me, but it usually takes a long tme to boot up after clearing the dalvik-cache.....

Not sure if you have installed the android sdk on your PC to use adb - http://developer.and.../sdk/index.html
Once installed, you go to the platform-tools directory of it via the command prompt (where adb.exe is located)
Edit: Something simpler to use may be the download from Zenithink - http://www.zenithink.com/Eproducts_adb.php http://www.zenithink.com/UploadFile/ADB16R_and_USB_Driver.rar
Uncompress the RAR download somewhere, then via the command prompt on the PC (Programs/Accessories/Command Prompt), go to the folder where the adb.exe file is located (ie - cd C:\ADB16R_and_USB_Driver)

and then connect your tablet to your PC via the OTG port then type the following via the command prompt on your PC:
adb remount
adb shell "rm /data/dalvik-cache/*"
adb reboot
 
#3 ·
and then connect your tablet to your PC via the OTG port then type the following via the command prompt on your PC:
adb remount
adb shell "rm /data/dalvik-cache/*"
adb reboot
Thank you so much for coming to my aid, omarahum!

Which port is the OTG port? I presume it's not the USB port, and if it's not, I don't know what kind of cable I'll use to connect it to the PC.

Lane
 
#4 ·
Another question: If I recall correctly, when you flash a ROM, you lose everything you've added since you bought the device. Is that correct?

I'm downloading from Zenithink.com the ZT282_H3_1a_1GB_C91_Android4.0_0702_V1.4.zip file. I presume it's what I would use to reflash the ROM. Its version is Android4.0_0702_V1.4 while my current one is Android4.0_0327_V1.16 , but I presume that's OK.

Or might I see an improvement if I flashed one of your ROMs instead? I would like to do that, if I wouldn't mess something else up. I've seen posts from people who lost this and that capability from a flashing. Of course, I guess I could always go back to the "official" one above if things didn't work out.

Lane
 
#5 · (Edited by Moderator)
Yes, with the default command file that comes in the ROM, everything usually gets erased, that's why it would help you get your tablet working again, but you will lose all your data.... You can edit the command file (with a txt editor) and place a # infront of any of the wipe commands you don't want it to wipe, but in this case, with your tablet not being able to fully boot into Android, it would be better that you wipe the data partition at least or the whole tablet....

Yeah, the 0327 was compiled on March 27th and the 0702 is the newest (July 2nd)....

The 0702 ROM is set to 1GHz by default, so you wouldn't need to use one of my OCed kernels, and it seems you are cutting back on the apps on your tablet, so you wouldn't need my 2GB data partition mod kernel/recovery files either... But feel free to try anything you'd like, I hear swoody13's Zenidroid ROM and justinthegeek's ROM are pretty good, I only modify the kernel or recovery file to change the CPU 's max freq and the partition sizes of the nand....

Again, you can reflash a ROM onto your tablet if the adb thing doesn't help you, but you should try to see if it helps make your tablet boot up fully first....
 
#6 ·
The continuing saga...

I tried adb, but the boot was too erratic to allow me to mount the tablet to the PC. It never stayed connected long enough; at least, that's what I think was the problem.

I'm flashing the ROM now with the files I downloaded. It seemed to start OK, which was a great relief. I had to confirm that I wanted to do the update by pressing the Camera button. The screen now shows some text with this at the bottom:
System updating start...

It's been a pretty long time since it started. Will it tell me when it's finished?

Lane
 
#7 · (Edited by Moderator)
Hmm, after you typed in adb remount, what did it say? there shoud have been a # prompt if it did connect..... (Sorry, the previous sentence was if you typed adb shell, not adb remount...)

So you are flashing your tablet to 0702 I guess... You should be seeing the same thing as the last time you flashed your tablet, did your tablet freeze at the System updating start...? As with all the Zenithink ROMs, it should reboot automaticaly after it's finished updating everything....
 
#10 ·
I run Linux on my main machine, and I installed the full SDK package. I connected the frozen (as described above) tablet and tried a few adb commands. Here's what I got:
root@pc1:~/android-sdk-linux/platform-tools# ./adb devices
List of devices attached
0123456789ABCDEF offline

root@pc1:~/android-sdk-linux/platform-tools# ./adb remount
error: device offline

root@pc1:~/android-sdk-linux/platform-tools# ./adb shell
error: device offline

I was hoping the port would be available, but I guess not.

Lane
 
#11 ·
Hmmm, I'm not a linux user, so I probably won't be able to help you....

Yes, adb won't work when the tablet is frozen, but will while you see the animated android text bootanimation, even if it doesn't fuly boot to android...

On windows, two years ago, we also had to download the Google USB drivers using the SDK Manager, I'm not sure if you need to do that for linux, but if you are seeing two drives, it seems like your computer does recognize the tablet....
 
#14 ·
I just did the flash with the four logo files included, and it behaved quite differently. However, it still froze with this on the screen:
IMAGE updated!
System updating start...


I turned off the unit and restarted it. The ZTPad logo came up twice, as it should, and then the Android logo ran for a whiile. But then it "pop!" and everything started again. Subsequent recycling does not get to the Android splash.

I tried adb while it was trying to boot, and sometimes I could at least get a response:
root@pc1:~/android-sdk-linux/platform-tools# ./adb devices
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
List of devices attached
0123456789ABCDEF offline

root@pc1:~/android-sdk-linux/platform-tools# ./adb usb
restarting in USB mode
root@pc1:~/android-sdk-linux/platform-tools# ./adb remount
error: protocol fault (no status)


adb remount just showed the device offline until I tried the usb parameter. Then remount just sat there with no output. Turning the unit off generated the final error.

Following your suggestion, I'm going to try to flash the 0327 ROM later today.

Lane
 
#15 · (Edited by Moderator)
No joy with 0327. It basically proceeded the same as before and now shows on the screen:
Prepare enter mmc update mode
IMAGE updated!
System updating start...


I assume there should be very little delay after the above is displayed and then the device should boot normally.

So I turned the device off and then on again. The ZTPad splash displayed off and on about five times. Then the Android splash came on and ran for a while like it should. Then it froze and pop! here we go again. Very discouraging.

It seems like something's wrong somewhere, but I suspect it's not in the ROM, since I saw identical behavior after flashing both 0327 and 0702... assuming the flash was successful.

I can only get adb to recognize the device while the Android splash is on, and one time it seemed like it was doing something
root@pc1:~/android-sdk-linux/platform-tools# ./adb remount
remount succeeded
root@pc1:~/android-sdk-linux/platform-tools# ./adb shell "rm /data/dalvik-cache/*"
root@pc1:~/android-sdk-linux/platform-tools# ./adb reboot
error: protocol fault (no status)


So it looks like the remount worked, but I don't know if the shell did anything since there was no output. The error was generated as soon as I executed the reboot command.

It doesn't seem like it's "bricked," since the ROM flash seems to work and the thing tries to boot, albeit unsuccessfully. OTOH, if the defect is in the BIOS (or whatever code there is before it gets to the ROM), I guess it's the same as being bricked.

Lane
 
#16 ·
Hi Lane, I'm assuming your circumstance is different, but, one trap I fell into with a tablet was that I was so focused on trying to fix and reflash the tablet that I did not realise that the battery had become dangerously low. The failures I was having were due to the tablet switching itself off because it was not meeting power requirements. I'm assuming you have the tablet plugged in?
 
#17 · (Edited by Moderator)
That's sort of the modern equivalent of "Is the computer plugged in?" :)

Seemingly a silly question, but really not. In my case, I had it on AC when the thing went "Pop!" the first time.

Now it seems to pop and reboot at the same point every time: during the Android splash phase. So there seems to be something definite that's causing the roadblock.

I have a bad feeling my tablet days are over for now. I bought it from China ($180 total), so I'm looking at $35 shipping each way, even if the warranty is still good.

Lane
 
#18 ·
And the reverse of that position, are you flashing the tablet with the power adapter plugged in? - another lateral thinking approach is to try flashing with the power adapter removed, ie, is it the power that is causing the pop? - just randomizing, but sometimes doing something different helps.
 
#19 ·
That's a good suggestion. I'm not sure if I did the flash with the power plug in, but I know I've done it a couple of times with it not plugged in.

The tablet has always made a pop when I shut it off with a paper clip in the little hole. It does sound like a spark. And it's the same pop when the boot process crashes during the Android splash phase.

Lane
 
#20 ·
Well, I don't know how easy it is to open your tablet, but, I know you've had it a bit so perhaps there is no "implied or inferred" warranty on it, plus, you know it will cost to ship it back, tracked. So, if all else fails, wiggle.

I would open the tablet and go through all the physical connections to see if they are good, I know my ZT-180 is easy to open, but yours may be more of a monkey puzzle, plus have a few of the warranty stickers present, so it's that bridge too far so to speak, open it and you forfeit the sending it back option.

Of course, we all know the reality of the sending it back option, so opening it is not such a decision, open, observe, wiggle.

If you're like me, fixing toasters is rocket science nowadays, so all we can do is see if the connections are good. You can also boot the thing and see if you can identify precisely where that pop is coming from.

And, I always encourage users, in the interests of science, to take pictures for the drooling masses.
 
#22 ·
Thanks for the suggestion, dryster. I have no hesitation about opening the thing up. I've done it twice before, as I described in the thread (with photos) How to Open Case; Getting Green Jaggies. Then I was looking to firm up the screen connectors. I didn't even bother putting the two little screws back in, since the clips hold the case tightly closed.

So I popped it open again. In addition to the two screen connectors, I only found one more connector, and it's snug. Just about everything is soldered, unlike a desktop PC.

I followed your suggestion and booted the device while it was open. I determined that the pop comes from the speakers and not from an internal spark.

There are two kinds of errors, as I see it. One is seen when the ZTPad splash occurs more than twice after turning the unit on. Normally it appears only twice, and then the Android splash comes on. After several appearances of the ZTPad splash, the Android splash comes on for a while, and then the second kind of error occurs, the pop. This seems to start the whole thing over again.

I don't know if the ROM flashing is doing as it should or not, since the unit freezes after these messages appear:
Prepare enter mmc update mode
IMAGE updated!
System updating start...


And thanks, Ben36, for the thought about charging. The unit has been well charged during these attempts.

Lane
 
#24 ·
Are all the files correctly in the folder and is the command file right? Maybe it can't find something it has to flash so just freezes up?
How would I know? I'm just copying the folder from the zip file to the sdcard and firing up the Z with Camera-Power.

I would think this means it started OK:
Prepare enter mmc update mode

I would think this means it flashed OK:
IMAGE updated!

I would think this means it's trying to do some more updating:
System updating start...

...which never gets finished.

Lane
 
#25 · (Edited by Moderator)
Once you see the System updating start... it should be loading the ZT282.recovery file and following the instructions of the command file (what partitions to wipe, and what files in the zt-update folder to copy/untar onto your tablet).... This is the step which seems to be missing from your update attempts.....

I'd say try to flash the 0327 ROM onto your tablet, incase the 1GHz kernel and recovery files of the 0702 is causing you the problems.....

If you are still can't fash your tablet, even with the 0327 ROM, you may want to contact Zenithink....
http://www.zenithink.com/Efaq.php
1. How to deal with power-on issue?
If you meet the following problems during power-on process, please kindly contact with our techinical support via Email bcjiang@zenithink.com.
1. Black screen or no display output when power on, but the green light is on.
2. Upgrading is failure or hang during upgrading process.
3. Upgrading is success, but hang during rebooting with "ZTPAD" or "ANDROID" displayed on screen.
 
#26 ·
Once you see the System updating start... it should be loading the ZT282.recovery file and following the instructions of the command file (what partitions to wipe, and what files in the zt-update folder to copy/untar onto your tablet).... This is the step which seems to be missing from your update attempts.....
The recovery file seems to be executable code, not a script. The command file is mostly commented out, but there are a few lines that make some sense. All the files that command is looking for seem to be present.

I'd say try to flash the 0327 ROM onto your tablet, incase the 1GHz kernel and recovery files of the 0702 is causing you the problems.....
I already did that, and the results were the same as the 0702: freezing without rebooting.

If you are still can't flash your tablet, even with the 0327 ROM, you may want to contact Zenithink....
http://www.zenithink.com/Efaq.php
Thank you for the link. Following that suggestion, I have now emailed them with a description of the problem and what I've tried.

It sure would be great if they would provide warranty service within the US, since it would cost me $35 each way to send it to China... which I won't do.

Lane
 
#28 ·
#29 · (Edited by Moderator)
Have you got your tablet working yet? Any reply from Zenithink?
Not working and no reply yet.

That link opens an FTP session, and there are several folders listed. Am I correct that the correct folder is /pub/ZT282_NoBlueTooth and the correct file is M3C91_nobluetooth.rar?

I believe I have posted about the 0702 ROM on the Zenithink FTP before (where because of the included autoscript, you just power on the tablet to autoflash - no button combination to flashmode , and remove the autoscript and spl after a successfull flash)...
Is the autoscript in the zt-update folder? I'm surprised to learn that an 03027 tablet would have in its BIOS the command to look for a script in the /sdcard/zt-update folder every time the power button is used. But maybe it does.

I have just copied the contents of the 16 GB sdcard (the only one I own) to my hard drive. I am now going to wipe it and reformat it. Then I'm going to put the files that expand from the above-mentioned M3C91_nobluetooth.rar on it. Then I am going to power up without pressing the Camera button... at least for the first try.

Thanks again for sticking with me on this; I really miss having the tablet in my life.

Lane
 
#30 · (Edited by Moderator)
I used the Linux program GParted to erase the partition on the sdcard (every filesystem has at least one partition), create a new ~16 GB partition and format it to FAT32.

I copied to the empty sdcard the zt-update folder from M3C91_nobluetooth.rar and inserted the sdcard into the ZTPad.

I started the tablet with only the power button. It did not seem to access the sdcard, although it did a bit of extra flashing of the ZTPad splash before it switched to the Android splash, which cycled for a while before pop! and the process started over again.

I turned off the tablet power with a paperclip and then restarted it with Camera-Power. It recognized that the Camera button was depressed and brought up the different ZTPad splash, displaying the familiar
Prepare enter mmc update mode
IMAGE updated!
System updating start...


...and freezing as usual.

But I certainly appreciate the opportunity to try something else. I'm always willing to try!

Lane
 
#31 · (Edited by Moderator)
I compared the zt-update folders from M3C91_nobluetooth.rar and ZT282_H3_1a_1GB_C91_Android4.0_0702_V1.4.zip and found they were not the same. Here are the files listed in each:

M3C91_nobluetooth.rar
media
system

command
data.zt280.tar.bz
media.zt280.tar.bz
system.patch.zt280.tar.bz
system.zt280.tar.bz
ZT282_H3_1a_1GB_C91_Android4.0_nobluetooth.txt
ZT282.kernel
ZT282.recovery

ZT282_H3_1a_1GB_C91_Android4.0_0702_V1.4.zip
media
system

command
data.zt280.tar.bz
media.zt280.tar.bz
system.patch.zt280.tar.bz
system.zt280.tar.bz
ZT282_H3_1a_1GB_C91_Android4.0_0702_V1.4.txt
ZT282.kernel
ZT282.recovery
ZT282.sd
ZT282.spl

Noting the former did not have a ZT282.spl I deleted the former's zt-update from the sdcard and copied onto it the zt-update from the latter.

Regretfully, it all behaved the same as with the former zt-update, whether starting with only the Power button or the Camera-Power combo.

Lane
 
#32 · (Edited by Moderator)
Sorry for confusing you, i thought deskwizards post was pretty straight forward....

I meant for you to try this 0702 ROM on the FTP - ftp://zenithink.cn:1...0_0702_V1.4.zip

As it contains an autoscript file, you should put the zt-update folder on your sdcard, insert it into the tablet, and then just power on for it to auto-flash....

If it does succeed (or I guess even if it doesn't), remove the autoscript file and the spl from the zt-update folder so it doesnt try to autoflash again the next time you power on your tablet....
 
#35 ·
I meant for you to try this 0702 ROM on the FTP - ftp://zenithink.cn:1...0_0702_V1.4.zip

As it contains an autoscript file, you should put the zt-update folder on your sdcard, insert it into the tablet, and then just power on for it to auto-flash....
Too many different threads of thought here, so let me address just one with this reply.

If the filenames are accurate, the above-linked file is the same one I got a couple of days ago via HTTP from the Zenithink site and have tried to flash several times:
ZT282_H3_1a_1GB_C91_Android4.0_0702_V1.4.zip

I'm downloading the one you linked, and I'll compare it to the one I already have, to be sure they're the same.

The most recent attempt with 0702 was what I reported earlier today, where just pressing the Power button did not execute any script. Only pressing Camera-Power would do anything other than the failed boot cycling.

Lane
 
#33 ·
@omarahum

Is there any way to externally analyze the boot progress on the device? - it seems that something is working, access to the SD card and the update files etc. Can a script be written that will log the events to a text file on the SD card so that LL can see what is actually happening from a system point of view?

LL could then read that text file on his PC and upload it here.

I have no idea how to do it, but it is logical that it can be done, especially if the tablet is reading a script from the SD.
 
#34 · (Edited by Moderator)
I remember deskwizard mentioning a recovery log in /cache/recovery/last_log, but again, since I don't have this tablet, and the ZT-280 that I do have doesn't seem to behave the same as the ZT-282's, I don't know if there is anything that's on the sdcard that gets outputted...

If he had adb working, he could try to see the logcat or dmesg to see why his tablet isn't booting fully with what's on his tablet already...

Sorry, wish I could help more, but have limitied knowledge of Android, and even less about the ZT-282's, and even less than that with Linux....
 
#38 ·
I remember deskwizard mentioning a recovery log in /cache/recovery/last_log, but again, since I don't have this tablet, and the ZT-280 that I do have doesn't seem to behave the same as the ZT-282's, I don't know if there is anything that's on the sdcard that gets outputted...

If he had adb working, he could try to see the logcat or dmesg to see why his tablet isn't booting fully with what's on his tablet already...
adb is working just fine, but the tablet has to be polling the device port to get a connection. I've observed that the port is not available during the ZTPad splash, but become available during the Android splash. Unfortunately, the Android splash lasts only a brief time before the pop! and the tablet reboots.

Lane
 
#37 ·
I think that whatever is being flashed will probably end in the same behaviour, so to get to the "root" of it, a bootlog needs to be created, to see where the log actually fails. Again, I'm in the same boat as Omarahum here, I have just enough knowledge to make myself dangerous.
 
#42 ·
Lane,
Does the tablet ever gets to actually flashing files?
My guess would be no.

Random guess: (some already mentionned)

1) bad sd card
2) wrong spl (wrong tab, not wrong version)
3) internal flash is dead
4) none of those

I never had my tab stop at the updating system image... part.
The first thing it does (as I understood) is mount the sd card and mmc, that is why I keep coming back to those.

I will try to make myself a 3.3v serial adapter and check if we have the u-boot console on there...
don't expect this to be quick/easy thought...

When flashing the SPL, the message was SPL match right?
Maybe its just #2...

Sorry not to have more insight to give you...

DW

PS: did you try to make a rescue SD card?
 
#43 ·
Thanks for the thoughts about my problem.

Lane,
Does the tablet ever gets to actually flashing files?
My guess would be no.
Something gets flashed, because the boot without sdcard has changed. The original boot problem was: ZTPad splash > ZTPad splash > Android splash > Pop sound in speakers > Repeat previous steps forever. Now the boot is: ZTPad splash > ZTPad splash frozen forever.

PS: did you try to make a rescue SD card?
No.

We have a new development. I received a reply to my email to jjyang@zenithink.com. He (or she) sent me a new ROM zip 0809 to try. He said to be sure to have the unit >80% charged and to leave the AC connected while flashing. There was some difference in what I saw during the flashing process. Here is my report to him:
The ZTPad update splash (logo with star background) came up, went off, came up again with text at the bottom:

IMAGE updated!
System updating start...

Then there was something big and yellow that flashed briefly on the screen (not seen in other ROM installs), and the screen went dark and stayed dark. It's very dark gray, not totally black with no signal. The green LED is lit.

I powered off with a paper clip, removed the sdcard, and powered on. The usual ZTPad splash (no star background) came up, went off, came up again and stayed there permanently. It never switched to the Android splash. I have to use the paper clip to turn it off. This is repeatable.
I don't think I'll try anything else until I get another email from jjyang.

Lane
 
#44 ·
Hi Lane,

Thank you for the update with your issue.
I will follow this thread closely.
Sorry I can't do more for the time being, time is scarce...

If you send him/her another email, perhaps you could ask what those symptoms COULD mean,
maybe it could point us in the right direction.

DW
 
#46 · (Edited by Moderator)
I understand you have (had?) a mislabelled Z. Omahahum provided me with links for trying the 1n possibility. I used the 1n recovery and kernel with the 0809 package. The update process reported a version "dismatch" (sic), and I had to press the Camera button a couple of times to get it to proceed anyway. There was no change in the results.

I did not try the 1n .spl file, because Omarahum said it might brick the tablet, and I don't want to take a chance on that until I hear back from the Zenithink tech. I'll let you know what he says.

I also tried flashing the 0809 ROM 6 times, first with the command file and the rest of the times without. No difference in results.

Lane
 
#48 · (Edited by Moderator)
No I haven't had a mislabeled tab, but I was wondering if yours was.
deskwizard, I thought you said your tablet was labeled as 1n (barcode), but the 1a files work on your tablet.... So then don't you have a mislabeled tab?
Mine's 1n ... but then shouldn't the touchscreen stop working?
it's 1a ... damn sticker is messing with my head
 
#50 ·
Hope you feel better soon....
 
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