Fix Bootlooped Coby 7033 Tablets

[vampirefo.]

Yes, what I did is to use your boot.img for the fatload, then
Folken 7035's boot.img, recovery.img and system in CW Recovery.
and unfortunately the kernel failed to write completely. it stops with an error, let's say, half way...

I'll post the error when I have a chance to reproduce it.

Thanks!

Ok, sounds like his boot.img is bad, we need to get someone with a 7035 to give us their boot.img, hopefully another complete dump.

 

[chrisautrey]

Vampire,

I registered today just to say thanks. I've been following the 7033 development here over the last 2 months or so since I picked up a couple of these on a fire sale. I was originally looking for the root piece, but of course Coby being what it is, one of them boot looped on me today getting stuck at the Coby screen.

I pulled the info from the first post and eventually determined that I have the 32MB version so on try 2 I got right into recovery. Your walkthrough is great and I am now back to a functioning tablet. Thanks for all you do.

 

[vampirefo.]

I think over time many of these tablets will be caught in a bootloop, Coby's security measures were over the top on these tablets.
And that is what will cause the tablet to bootloop. Glad this worked for you and that you took the time to register and post your results, alot of people wont.

Best Regards
Vampirefo

 

[tpaine]

@ coby7035

Here is Folken's 7035 dump, I can't verify that it works as I don't have a 7035, you will need the system and boot.img from a 7035 to fix your 7035, the 7033 recovery will work for you.

Just now rooted and dumped a 7035-8. I used 2 broken tabs to make one good one. the othere is also 7035-8, so if you would like to test, i will put the bad one back together.

http://www.androidtablets.net/forum...eneration-3-devices-part-ii-3.html#post305736

Btw, the uncompressed boot.img is 125mb.

 

[coby7035]

vampinfo hi!
just tried with this new provided boot.img
heres what ive got while writing kernel :

mtd: successfully wrote block at 4400000
mtd: not writing bad block at 0x04500000 (ret 1 errno 2)
mtd: not writing bad block at 0x04600000 (ret 1 errno 2)
mtd: successfully wrote block at 4700000
[...]
mtd: successfully wrote block at 7400000
mtd: successfully wrote block at 7500000
error writing kernelfailed with error: -1

then it stopped...

any clue ?
i have no time to retry anything right away but i would appreciate any advice.

thank you!!

@tpaine: Thanks for the dump provided; I hope we can make it work on my 7035 eventually!!!

'7035

 

[vampirefo.]

vampinfo hi!
just tried with this new provided boot.img
heres what ive got while writing kernel :

mtd: successfully wrote block at 4400000
mtd: not writing bad block at 0x04500000 (ret 1 errno 2)
mtd: not writing bad block at 0x04600000 (ret 1 errno 2)
mtd: successfully wrote block at 4700000
[...]
mtd: successfully wrote block at 7400000
mtd: successfully wrote block at 7500000
error writing kernelfailed with error: -1

then it stopped...

any clue ?
i have no time to retry anything right away but i would appreciate any advice.

thank you!!

@tpaine: Thanks for the dump provided; I hope we can make it work on my 7035 eventually!!!

'7035

We still need below from tpaine and others that have 7035, Folken's 7035 didn't work for you could mean there are different versions just like the 7033 had two different versions that we know of.

adb shell

cat /proc/mtd


after reboot

adb shell

dmesg > /sdcard/dmseg.txt

upload dmseg.txt

 

[tpaine]

We still need below from tpaine and others that have 7035, Folken's 7035 didn't work for you could mean there are different versions just like the 7033 had two different versions that we know of.

adb shell

cat /proc/mtd


after reboot

adb shell

dmesg > /sdcard/dmseg.txt

upload dmseg.txt

Tab is on loan to a friend. I will get it and do testing in the next few days and report results here.

 

[pp_eagle]

Hi everybody, and thank you very much for all the time and effort that you have dedicated to this forum. Special thanks to forum members vampirefo. and mcclain_ts, for their great contributions.

I've got a Coby Kyros Mid7033-4 tablet. I tried to install Google Play some time ago, and, unfortunately, I bricked it. Before doing anything, I tried to make a Rom dump, so that anything I was going to do, might be reverted. But, unfortunately, the ROM dump was incomplete, and some of the files have 0 Kb size. However, system.tar is 199.310 Kb!!!

I wrote this other thread time ago, without any success:
http://www.androidtablets.net/forum/coby-generation-3/55280-coby-kyros-mid7033-bricked.html

Time has gone by, and now I've tried to flash the modified boot.img of this thread, by vampirefo, but my 7033-4 doesn't reboot on its own. None of the attached utscripts work for me. Neither the boot.img / recovery.img from mcclain_ts, together with any of the utscripts. :-(

I guess that my 7033-4 will need its own boot.img / recovery.img. However, I've tried to find a valid ROM dump out there, and I haven't been able to find any.

I've seen that the content of build.prop file is helpful. Fortunately, this file was correctly backed up from my original ROM. I've found it into system.tar. Below you will find a copy of it.

@Vampirefo: I guess that you might help me. Could you please tell me what else I cold try?

Thank you very very much.


(copy of build.prop file
# begin build properties
# autogenerated by buildinfo.sh
ro.build.id=IML74K
ro.build.display.id=IML74K 20120921.165703
ro.build.version.incremental=eng.timy.20120921.165703
ro.build.version.sdk=15
ro.build.version.codename=REL
ro.build.version.release=4.0.3
ro.build.date=Thu Apr 26 14:48:15 CST 2012
ro.build.date.utc=1335422895
ro.build.type=user
ro.build.user=timy
ro.build.host=urbetter-linux4
ro.build.tags=test-keys
ro.product.model=MID7033
ro.product.brand=generic
ro.product.name=MID7033
ro.product.device=vortex
ro.product.board=
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.manufacturer=unknown
ro.product.locale.language=en
ro.product.locale.region=US
ro.wifi.channels=
ro.board.platform=vc882
# ro.build.product is obsolete; use ro.product.device
ro.build.product=vortex
# Do not try to parse ro.build.description or .fingerprint
ro.build.description=MID Serials 4.0.3 IML74K eng.timy.20120921.165703
ro.build.fingerprint=generic/MID7033/vortex:4.0.3/IML74K/eng.timy.20120921.165703:user/test-keys
ro.build.characteristics=tablet
# end build properties
ro.opengles.version = 131072
#
# system.prop for vc882
#
#
# system.prop for generic sdk
#

ifeq ($(BOARD_USES_VIDEO_RGB888),true)
ro.sf.lcd_density=120
endif
#add by liao for default language and timezone
persist.sys.timezone=Europe/Madrid
persist.sys.language=en
persist.sys.country=US
#
# ADDITIONAL_BUILD_PROPERTIES
#
#ro.sf.lcd_density=120
dalvik.vm.heapstartsize=5m
dalvik.vm.heapgrowthlimit=48m
dalvik.vm.heapsize=256m
ro.config.notification_sound=OnTheHunt.ogg
ro.config.alarm_alert=Alarm_Classic.ogg
dalvik.vm.dexopt-flags=m=y
net.bt.name=Android
dalvik.vm.stack-trace-file=/data/anr/traces.txt

 

[vampirefo.]

@pp_eagle
I don't understand your post at all, either you didn't follow instructions, or you haven't posted what you have tried.
Your post implies you flashed a boot.img you don't post how you did that, you state you bricked your tablet yet you can flash a boot.img doesn't make any sense.
Too many details are missing, so start from the beginning and post exactly what you have done or tried to do.

 

[pp_eagle]

@vampirefo:

Thanks so much for your fast answer. And sorry for not being clear enough. I will try again. This is what I did:

- April/2013: I was given a new Coby Kyros 7033-4 tablet, as a gift. My first tablet.
- I realize that it doesn't include Google Play. The tablet needs to be rooted, and some googleapps to be updated, in order to install Google Play. I find some posts containing the procedure. I've got some technical knowledge, so I decided to perform the "update".
- I consider myself a careful and prudent user. So, before doing anything, I made a ROM dump (incomplete, as I discovered later on). Though I tried to, I couldn't install CWM recovery. Seems to be a difficult task at this particular tablet model.
- Anyway, I continued with the update. I succeded in rooting the device. But I couldn't install properly the googleapps needed. At this point, I changed some permissions, or I forgot to change some file permissions during copy/paste googleapps files, and, with next reboot, the device entered in bootlooping state. I said bricked tablet, but I'm not sure whether mine is a bricked tablet or a bootlooping tablet. It just shows the Coby logo while booting, and it stays like that forever.
- I put the tablet back in its box, and kept it in the wardrobe. And posted the thread at this forum (http://www.androidtablets.net/forum/coby-generation-3/55280-coby-kyros-mid7033-bricked.html).
- February/2014: I enter this forum again (I use to enter from time to time), and find this thread.
- I think that this might be the fix for my tablet.
- I try your method. With the 3 different utscript files. With both your .img files, and mcclain_ts' ROM dump files. Both boot.img and renamed recovery.img. None of the combinations is able to reboot my tablet automatically after flashing boot.img.
- I'm able to manually enter recovery mode after every try. But ADB is disabled. I get the typical error at my desktop computer "device attached: 1234567890ABCDEF offline". If I try with my smartphone, ADB works OK, so I guess USB drivers & SDK tools are correctly installed at desktop computer.
- In my opinion, the microSD isn't the problem. I could see its contents from recovery mode (apply update menu item).
- I wonder if my tablet is that third 7033 model that you were looking for. (?)
- I see that utscript needs to be adapted for every specific 7033 version. That's why I posted a copy of my original build.prop file, extracted from the ROM dump I did before anything, just in case it could be helpful. Probably, most of my original system.tar dump is OK (I'm not sure). It weights 199.310 KB. Unfortunately, recovery.img weights 0 KB. And I can't find boot.img at my dump.

And that's all. I can try to give you a more detailed explanation about any of the previous steps, if needed.

I will appreciate so much your help. Please, if you have the time, tell me what else I could try, or retry, to fix the tablet.

Thank you very much.

 

[pp_eagle]

@vampirefo:

I've been looking into the incomplete ROM dump I did before anything.

There is a compressed file, named system.info.gz. It contains a text file named system.info. Please, take a look to the beginning of that text file, I think it could be helpful, because it shows up the memory map and the device mounting table of my 7033-4 tablet. It is different from yours, and from mcclain_ts':

Android ROM dumper v0.82b

## system memory map

60026000-60027000 : galcore register region
60030000-60030408 : musb-hdrc
60031200-600313ff : vc088x-ohci

60031200-600313ff : ohci_hcd
60031400-60031fff : vc088x-ehci

60031400-60031fff : ehci_hcd
60043000-60043fff : v8-uart
60044000-60044fff : v8-uart
60045000-60045fff : v8-uart
60046000-60046fff : v8-uart
97400000-9b3fffff : galcore managed memory
9f400000-9fffffff : fb_mem

97400000-9b3fffff : gpu_mem
60026000-60027000 : gpu_base
60047000-60047fff : v8-i2c.0
60048000-60048fff : v8-i2c.1
80000000-923fffff : System RAM

80030000-80587fff : Kernel text

80588000-8073dd6f : Kernel data
ff033000-ff033fff : v8-sdio.0
ff034000-ff034fff : v8-sdio.1
ff035000-ff035fff : v8-sdio.2

## mtd
table
dev: size erasesize name
mtd0: 00a00000 00200000 "SysInfo"
mtd1: 00a00000 00200000 "Uboot"
mtd2: 00200000 00200000 "Resimg"
mtd3: 01600000 00200000 "Security"
mtd4: 06200000 00200000 "kernel"
mtd5: 01c00000 00200000 "RKer"
mtd6: 18000000 00200000 "System"
mtd7: 68000000 00200000 "Data"
mtd8: 20000000 00200000 "Cache"
mtd9: 55200000 00200000 "user"

mtd10: 00400000 00200000 "bbt"


I could send you any file of my ROM dump, or the whole dump, if you want.

Thanks again for your help.

 

[vampirefo.]

Your output is different, and that would make your tablet the 3rd version of 7033.

However knowing that doesn't help, unless someone reading this thread having the same version as you uploads the required dmesg.

Until I get it nothing I can do, I can't guess on kernel / bootloader entry points.

You tried both files I made, neither worked for you, so your entry point is different than the two I know.

I never guessed on them either, I was given the information I needed to calculate the entry points.

 

[angellugo2012]

Greetings to all.


and followed this thread from several months ago, hoping if aver achievement also get my kyros tablet 7035. which also remained in logo COBY and from there wanted not to progress, I'll be awaiting this thread if surgue some progress ..

 

[coby7035]

Hey again!!

So, Ive been retrying to work with vampirefo<s great tool
Both MID7035 boot.img writing process wont come to an end, it stops with an error about in the middle of it.

Lets say I could write a Mid7033 kernel (boot.img) to the Mid7035 tablet.
I was at unTARing mid7035_system.tgz
Ive got a real bunch of :
tar: can't create symlink from xbin/findfs to /system/xbin/busybox: Operation no
t permitted

Anybody faced that ?

Anyway... after rebooting thru CW Recovery, its still stuck at COBY logo screen ! Vampirefo already told me that I shouldnt be able to use a 7033 boot.img because they are different.
Nonetheless, even its a 7035 tablet, it shows as a 7033 in Windows7 32 bits! Having nothing to lose, I tried anyway..!
LOL

And for the convenience of other mid7035 users, heres the link to the latest dump for 7035-4 (posted on april 25th 2014), personnally Im going try it right away. Ill post the result ASAP.

***UPDATE*
still the same error while writing boot.img from the dump file provided above...
"
mtd: successfully wrote block at 7300000
mtd: successfully wrote block at 7400000
mtd: successfully wrote block at 7500000
error writing kernelfailed with error: -1
#
"

 

[twisted_transistor]

Vampirefo.
Really thank you very much. I clean my Coby Kyros Mid7033, follow your job and the tablet it's a live again.
Thanks again and I recommended your job in my blog.