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Root Casio C771 Unlock Bootloader and Install GNM Recovery via Fastboot

rasta4rest

Member
Nov 3, 2012
55
16
First of all , Do with your own risk.. im not responsible for any damage caused by your action . Im just share my experience and trial , this trick is working for me To Unlock bootloader , flashing recovery with GNM Recovery from fastboot [Command Line mode] , and finally Root your device from GNM Recovery. This is just alternative root method , i dont think it's an easier than THIS method but it's worth to try.

Im on M110 Build , still hoping for anyone here upload their M130 stock build , since i cant get OTA Update from here. But i guess this method work for all build.

The starting point is here :
In the Program Menu (##PROGRAM aka ##7764726, pass 000000) I found a setting called Bypass Booting and was wondering what it was. It is set on Disable and I don't dare enable it so I was just wondering what it does and if it would help in any of our endeavors.

I searched both the forums and Google and really haven't come up with any real results.

I've guessed that "Bypass Booting" was bootloader lock "bypassing", but how can i use that to install recovery from stock device without root access ?

Here's the step by step guide assuming everyone here has been enabling "bypass booting" - ON & C771 Boot Loader Interface driver installed on their device , just googling it or search on this forum to get the correct driver:
1. Download ADB , since im doing all my stuff from there and make sure to connect your device in computer with Debugging On [ see Setting > Application > Development > USB Debugging ] and Charge Only mode. [see attachment for ADB package for windows]

2. Execute this Command from Command Line [ im using Windows Command Line ] to Enter C771 Bootloader :
adb reboot bootloader
you should see stuck on G'zone logo on your Device after the process completed.

3. Check device already connected and can do the fastboot command
fastboot -i 0x0409 getvar version
- the command should have result = version: 0.5 <-- or something like that , it means the device already connected [ 0x0409 --> Vendor id of C771 ]

4. Assuming you're already have GNM Recovery image on you PC do this following command :
fastboot -i 0x0409 flash recovery "path-to-GNM-recovery"
screenshot of mine on attachment for example.

5.
When you see something like this on CMD Windows :
sending 'recovery' (6748 KB)...
OKAY [ 1.689s]
writing 'recovery'...
OKAY [ 1.106s]
finished. total time: 2.797s
That means the flashing process already done and succeed.

6. Now boot to Android with this command :
fastboot -i 0x0409 continue
no need for disassembly battery anymore from bootloader interface and continue to normal booting.

7. After booting process completed and your PC detected your ADB interface again. Run this command from CMD Windows :
adb reboot recovery
and you'll see GNM Recovery installed on your C771 Calculator eh sorry i mean Android Device. :D

8. Make Yourself familiar with GNM Recovery Interface on you Device , you can do root and anything you could normally do from Recovery Interface.
I'm still waiting for someone Cooking Custom ROM from this lovely calculator :D.

9. This is personal advisory , do a NANDROID BACKUP is strongly recomended first action after all of this done.
You should at all cost avoid to wipe /Sytem , /Boot , /etc except you really need to brick your phone for doing some development.



PS : I would prefer THIS TRICK. Once again , this is only an alternative method especially for you who have wifi error problem after rooting and lost superuser access , or accidentally restore to factory default , hoping the wifi problem gone suddenly by itself
 

Attachments

  • ADB.zip
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  • Fastboot.png
    Fastboot.png
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That's not unlocking your bootloader?
Try
fastboot oem unlock
M

Fastboot oem unlock , wont do anything on this "special" device.

Try:
fastboot -i 0x0409 oem unlock 0xKEY
but i dont know where to have the key.

Above trick just for unlocking to enable flashing GNM Recovery,not to enter fastboot mode (it's disabled i think).
It's just my opinion :-D
I just did it without root access to gain root.
 
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ok I got all you shown in the screen shot
but when I adb reboot recovery I get this screen


IMG_20130107_204814_zpseb59fc08.jpg


what to do

- I assume you have correct driver installed on your PC also you're already familiar with ADB Command.
-Are you sure have enabled bypass boot from device's program mode ?
-Make sure your device detected as bootloader interface in your pc.
fastboot -i 0x0409 getvar version
To check fastboot command has already recognize your device.
- put that gnm recovery .img on your one of Pc partition.
(In my case i put it on D:\casio\gnm_recovery.img)
- bold numeric was Vendor Id of casio,it's global for all Casio Commando.
- the screenshot was just example,please read through entire guideline step by step.
 
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drivers installed, used the drivers provided and windows install some as well

Snap4_zpse12d9ab3.jpg



step1

Snap1-1_zps6ee128a3.jpg


step 2

Snap2_zpsd165be8e.jpg


step 3

Snap3_zps401b4201.jpg


and of course

what I get after I posted all ready
as you can see where I am grabbing the recovery img from in the screen shot
all commands executed successfully
I did a button combination only to get recovery screen that prompted me if I wanted to do a factory reset ..when all else failed as well
and yes
I went into the dialer and added ##7764726 hit send the I had the little windows to add the pass 000000
navigated to enabled bypass boot and it was off I did turn it on...

I followed it step by step..

and I'm very familiar with the cmd / shell I would on Linux servers and centOS Ubuntu etc
thanks for your reply
 
Upvote 0
drivers installed, used the drivers provided and windows install some as well

Snap4_zpse12d9ab3.jpg



step1

Snap1-1_zps6ee128a3.jpg


step 2

Snap2_zpsd165be8e.jpg


step 3

Snap3_zps401b4201.jpg


and of course

what I get after I posted all ready
as you can see where I am grabbing the recovery img from in the screen shot
all commands executed successfully
I did a button combination only to get recovery screen that prompted me if I wanted to do a factory reset ..when all else failed as well
and yes
I went into the dialer and added ##7764726 hit send the I had the little windows to add the pass 000000
navigated to enabled bypass boot and it was off I did turn it on...

I followed it step by step..

and I'm very familiar with the cmd / shell I would on Linux servers and centOS Ubuntu etc
thanks for your reply

Awesome :D
Then right before command
fastboot -i 0x0409 flash recovery GNM_img
try executing this command
fastboot -i 0x0409 oem unlock
Maybe that's the missing part.
 
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Upvote 0
I just rooted my droid commando. thanks to all the information on this forum. Like Hippy I have M130 and tried to flash recovery as described above. during recovery reboot I get screen shown by hippy. no options. I have to remove my battery to reboot to desktop. at this time what other recovery flash can I try? anyone out there with a m130 get this to work?

thanks
 
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Upvote 0
i just realized that I did not use the right image file. I didn't know that the commando had its own. I just downloaded the img file at the top assuming it was the latest version without paying attion to the acronyms.

thanks monky.
now that I have GNM recovery installed, i created a backup and started peeling off stock applications. my assumption is that the recovery flash I recovered in the dump files is no longer the stock since i was flashing the wrong one. how can i tell if its stock or not?

thanks again.
 
Upvote 0
i just realized that I did not use the right image file. I didn't know that the commando had its own. I just downloaded the img file at the top assuming it was the latest version without paying attion to the acronyms.

thanks monky.
now that I have GNM recovery installed, i created a backup and started peeling off stock applications. my assumption is that the recovery flash I recovered in the dump files is no longer the stock since i was flashing the wrong one. how can i tell if its stock or not?

thanks again.
so whats the right recovery for the c771 M130
2.3.3
in the thread you posted all in one recovery is where you get GNM ?

thanks
 
Upvote 0
Use the menu button of the phone....bottom left of your screen to execute your highlighted action. First thing you shud do is make a backup before you start peeling stock apps.
Goodluck
thanks very much for the detailed answer
for the noob

I did figure it out today playing around at luch

I did a nfull nadroid back up..
now I need to figure out what can go with out issue

thanks again
 
Upvote 0
So I got it to the stuck G'zOne logo

adb devices returns a blank list?

If I try fastboot it comes back:

'fastboot' is not recognized as an internal or external command, operable program or batch file

Driver missing? Or it didn't install the recovery... You unlocked the bootloader? Us terminal. Su reboot recover. You should have the Droid screen with options you us the volume buttons and the touch screen to make the backup
 
Upvote 0

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