I’m a dev changing the horses, sniffing around on the Android platform. Originally wanted to start with “user” apps development (*), then hack slightly deeper into the architecture and internals. After a short sniff on my brothers TrekSTOR HD7 I searched for the best HW I could find and despite some logistic problems of getting my hands on it, I got the Tegra Note 7 (and its really great! I would say WOOOOW, more then WOW64, probably WOW128 ;-)
Before I could even start as a user-app dev, after a few days of BFU-only settling-in and playing around my device hung miraculously - after power on it goes through the first logo and than starts the animated one where it hungs for about 15-20 minutes, before I switch it off. If Im correct, this means, that either the init or the Zygote & Dalvik VM inicialization hangs somewhere.
Diagnostics so far:
I was never able to get it into the fastboot menu (power+volUp), when I needed to root it (droid 4.2.2) I had to restart it into fastboot through an ADB command.
(ok, I rooted the device about 2 weeks ago and I’am afraid that I messed up something using a full TitaniumBackup restore yesterday)
Thus, I have no way to do a “factory” restore - when started normally (and the USB debugging was ON as far as I can remember) it does not get so far to be seen on ADB and I have no way how to boot to fastboot protocol to do the recovery from the fastboot.exe and the “hardware” way of PWR+VolUP does not work.
However Im able to get to the APX mode (driver installed, Win7pro64b), but thats the end of the story, since that is the final frontier for my knowledge so far
Special observation: when it hangs during the boot and I make a forced power-off (Power for about 6 secs, then immediate release when it shuts down), it suddenly (within 2-3 secs) powers on again!!! Only way how to get it off permanently is to hold the power+VolUp+Down untill screen blank, continue hold the VolUp+Dwn for about 30 secs and then it is still - no APX mode, but the APX can then be reached as usuall)
What I need to know:
- any other way I can force it to get to recovery (fastboot) menu, as I have seen on varius videos and on my brothers tablet?
- if not, how to restore it back to the original state flashing it in the APX mode?
OK, I admit, I have no idea, WHICH part (bootloader? main image?) is wrong and what should I flash and how, since I have no clue of how the internal memmory is organised and what and how can be rewritten (and where to get the files from - I have only backed up the big ZIPs with OTA updates from nvidia sites). Since I dug a little deeper, I understood, that if the part when the device hangs is it’s system “only” (init/Zygote/Dalvik), then only flashing only the system partition of the memory should be sufficient, but have no idea how to do it in the APX mode.
Can anybody help? When further info needed, I will provide as far as Im able. This quite embrassing for me, since I wanted to get to these internals anyway, but it came much too early :-/
(*) eg. not going further then inside the Dalvik VM, using AIDE - it is mostly TXT only, git integration, small and fast to understand and to understand the logic, the compiler sources etc., without all the havoc Eclipse/IDEA/Visual studio android projs. have