Colorovo CityTab 10.1 (RK 3066) - Rom dump, CWM recovery, and need some advice
First of all thank you - especially Finless - for those great howto and walktrough threads that helped me, a newbye android user to get familiar with my unknown device.
So, my tablet is branded as Colorovo CityTab Vision 10.1 (link), and looks like that for most part, it's a pretty much "standard" 3066 device. Specs are on the website. There is currently no official downloadable firmware for this thing, but they promised me to make the stock firmware available for download soon. The stock firmware is a 4.1.1 JB, with 3.0.8+ kernel.
Anyway, I managed to dump the stock rom. The backup partition is empty, so no update.img avail there. I could unpack and repack all relevant parts of the rom: boot, recovery, system, kernel. Flashed back, and working. So good so far.
Then I decided to try create a CWM recovery for this thing. I took the general ramdisk only CWM image from androtab.info, and using the stock dumped recovery.img, I yould create a working device specific CWM out of it. Haven't tested everything yet, but it's basically working: backup, restore, wiping cache-es, formatting, updating from zip works fine.
Now, the problems.
I cannot seem to be able to get into recovery mode by using hardware buttons. I tried many combinations (it has power, menu and vol+/vol- buttons), but no success. Power + vol- seem to doing "something", because by using this combination the tablet does not make any response (screen remains black), while all other combination which includes power, actually starts the device up. So I guess, the the vol- + power combination is detected, it just does not go to recovery mode.
My question is: what is responsible for bringing the tablet to recovery mode by this button combination? Is it the kernel? Or the boot loader? Or something else? And of course the question: Can this be fixed somehow?
My second problem is that this device came with an empty misc.img. If I flash a misc.img with recovery command in it, the device goes into recovery mode, on the next boot. But then, it boot-loops into that. If I select "reboot" (normal) in CWM, it still boots into recovery. Now, here is my problem: I don't know how CWM (and generally) recovery supposed to work? Is that the normal behaviour to write "reboot recovery" command to misc.img and reboot, and then, CWM should clear misc.img on reboot? Or CWM does not touch misc.img at all, and my tablet is special going into recovery-bootloop until misc.img is cleared?
So, utimatelly, how could I get out of this problem, and make CWM reboot work (clear misc.img for me on reboot)?
The dreaded kernel/initlogo.rle thing. The stock boot.img doesn't have a initlogo.rle, so the boot logo is built into the kernel. I found the mentioned "logo_RK", "logo_clut", "logo_data" marks, so it is definitely in there, but I just couldn't get it out, no matter what I tries. The tab is a 1280x800 device, but I'm not sure at all, that the image resolution is actually 1280x800. Then, I tried to create my own initlogo.rle. Used the tools available (convert from imagemagick and to565) and created a 1280x800 image, which is being displayed on boot, but in a wrong size, covering only the top half of the screen. To be precise, if I use the linux tools, it ends up displaying the image in the top half, if I use the windows similar tools, it displays the image twice, next to each other, again, in the top half of the screen...
My ultimate goal is to replace the img in the kernel, because it's simply awful. I selected an image that I would like to put into the "community" rom (which I would provide for my fellow Colorovo owners), and one image for my personal use. Links to the images are below.
I have uploaded the complete dump, and the re-created boot, recovery, kernel images, along with the above mentioned CWM recovery.img here on my skydrive space. Look for the file "colorovo_dump.zip". I have included the parameter, de mtd info and the beginning 0x2000 bytes of the NAND as well (to check if you want to check it). And there are 2 images - pictures - outside of the zip in there: initlogo.png and initlogo-personal.png (the two showing a CPU) which I would like to use as a boot image. (Both images are basically the same, I've just added a logo to my personal one.)
Sorry about this long post. I'd really appreciate if someone could spend some of his time on me and help solving my above problems.
I'm downloading your dump file right now...with your boot images.
Can you download and run an app that tells you exactly what your screen resolution is?
Thanks for helping me rrileypm.
Well, it's funny, I went to the plastore, and installed the first app that came up searching for "screen resolution". Then, just for the sake of curiosity, I've installed the second one, and it told me a different resolution. Wow, nice...
So, I went ahead and installed as many screen res app as I could quickly find, and the jury's majority decision become to be 1280x752. There were a few votes for 1232x800 though. I'd say let's go with the majority decision first...
Regarding rebooting to recovery, it is not a problem now. I've already added a new menu item to the switchoff menu which does a sdb reboot recovery, which works. So from the running OS it's easy to get to recovery now. The problem is how to get there if the device is bricked, wont boot at all. Currently, the only idea I have is to flash a misc.img containing the boot recovery command, but then, it wont get out of recovery boot-loop. So either I need to add a new menu option to recovery to clear misc.img, or I need to reflash it again with a clear misc.img once I'm done with the recovery tasks. I can personally leave with it. However, I plan to release this stuff for my fellow colorovo owners, who might not deal with this as easy as me. So if there is a better solution, then I'd vertainly welcome that.
The stock rom has 1280x800 in the bootanimation. Does it play ok?
Yes, it plays ok. Actually, I have already replaced the stock boot animation with my own. I set 1280x800 in desc.txt as resolution, and no matter what image sizes I use, it displays the anim nicelly in full screen. The kernel boot logo behaves somehow different...
I believe the image resolution is 1280x800. Opening the kernel img in a hex editor and looking for the "logo_RK" and "logo_data" patterns, the next 4 bytes are: 05 00 03 20. This is 1280 and 800. Too coincidental to not to be the resolution, I suppose... Doesn't help though. If I dd out the next 1280x800x3 bytes (assuming its a raw) then I can't open it with gimp no matter what options I try. Same result if I assume it's a rle image with corresponding size...
I have Colorovo CityTab 10.1 (RK 3066). I executed RK batch tool with a wrong firmware and now I am not able to start the tablet.
If I press power button and Volume - I can connect through USB, seems that RK batch tool detect my device corectly. Still I can see only black screen.
I have downloaded yor dump files hoping this help.
I am not able to restore your backup using RK android tool.
I need some help how to use this software.
Could you please help me and write a simple guide how to do it?