[G2 and Desire Z Android Development] gtrab:
ROOT - ROOTING the HTC DESIRE Z:

FREQUENTLY ASKED QUESTIONS​

1.- What is "root" ??

"Root" is the user account in Linux with all priviledges: The "root user" can edit anything on the system. For safety reasons, users do not have all those priviledges out of the box.

Remember: Android is Linux based. When you "root" your phone you gain write/read-access to areas of the phone you couldn't previously access.

Rooting the phone is optional of course.

2.- Why should I "root" my phone ??

Mostly, rooting is useful only for developers, unless you want to run a root-requiring app/mod or you want to flash your phone.

When you root your phone you are allowed to:

a) Run more linux (Android ADB) commands and use Superuser priviledges.

b) Use many apps that require root priviledges (Titanium Backup, Root Explorer, etc).

c) Change important system settings. In our case, rooting lets us turn off the ROM security in order to flash other firmwares and run some interesting tweaks like overclocking and installing hardcore recovery apps.

3.- Is "rooting" safe ??

Yes, if you read carefuly and follow the instructions nothing will happen.

4.- Will "rooting" erase all my info ??

No, it's just a change on system permissions.

5.- Will "rooting" void my warranty ??

Hmmm... good question, anyway you can always go back and un-root to pretend nothing ever happened :D

6.- After I have rooted my phone, can I uninstall the VISIONary tool ??

Yes.

Be aware that removing the VISIONary tool will NOT remove root ("un-root" your phone), it will only remove the rooting tool, obviously.

7.- Will I loose "root" if I uninstall (remove) the VISIONary app ??

No.

Paul's VISIONary app is just a rooing tool, root changes will stay.

8.- Is the process reversible ??

Yes it is.

9.- How do I "un-root" my phone (remove root) ??

Should you need to do so, just open VISIONary again, and tap "Unroot Now!"

10.- Can I flash a different ROM after I "root" my phone ??

No. To flash a non-official ROM (custom or unsigned) you need S-OFF. To flash an official (but not your orginal) firmware you need CID unlock.

Piece of cake, ain't ?? ;)

FLASHING the HTC DESIRE Z:

FREQUENTLY ASKED QUESTIONS​

1.- What is a "ROM" ??

"ROM" is "Read Only Memory". It refers to the phone's non-accessible, read-only internal memory. It contains the Android Operating System and all the original software that runs your phone.

Usually a FULL ROM (aka "firmware") consist of: a Recovery image, a Boot image (which contains the Kernel and the ramdisk), a System image (the operating system or "OS"), and a Radio image.

Frequently, we use the term "ROM" losely: we refer to a "ROM" or "firmware" as an image that can be flashed to that inetrnal memory.

There are "official" ROMs from HTC, and "custom" ROMs modified by users.

2.- What is "flashing" ??

Flashing is writing a new full firmware image ("ROM") or a portion of the firmware into your phone's internal memory.

You can flash a Recovery (like ClockworkMod), a Kernel (or boot image), a System (the OS), a Radio, or a full firmware which contains all of them.

3.- Why should I ever want to "flash" my phone ??

If you ever want to:

- Update your phone to a newer official firmware (since it's "official", this doesn't require root or S-OFF, and won't void your waranty).

- Debrand or downgrade your phone to another official firmware.

- Replace your stock ROM for a custom ROM, eg. with or without HTC Sense, other Android builds, etc..

- Install a better Recovery utility (like ClockworkMod or Amon_Ra).

- Change your Radio ROM.

- Replace the Kernel for an overclocked or modified one.

- Etc...

4.- What is "S-OFF" and why do I need it ??

Every phone has Security ON (S-ON) by default.

In order to get full write access (eg. to flash a firmware or install a custom Recovery tool) you need to turn S-OFF.

S-OFF is different from "root": S-OFF lets you flash unsigned images using the Fastboot option on the Bootloader or through a custom Recovery (ClockworkMod Recovery is the most used).

You need to run gfree (full S-OFF) or flash an Engineering hBoot (partial S-OFF) to switch S-ON to S-OFF. You only have to do this once, not every time you want to flash.

A flashed Engeneering hBoot S-OFF will be lost if an original ROM is flashed with an RUU, but getting S-OFF with gfree will stay even if an original ROM is flashed again, because gfree modifies partition 7 of your phone to disable the emmc's write protection, and removes the brq filter from the kernel: full S-OFF.

5.- How do I return to "S-ON" ??

If for some reason (sending phone for warranty or repair, etc) you want to go back to S-ON:

- If you got S-OFF by flashing an Engineering hBoot, download the official HTC RUU for your phone version and flash the stock firmware back again. S-ON will be restored. This forum contains many threads with official RUUs.

- If you got S-OFF with gfree, it saved a backup copy to your SD card called "part7backup-xxxxxxxxxx.bin". It can be flashed back from a terminal emulator or from an ADB shell:

"dd if=/wherever/your/part7backup-xxxxxxx.bin of=/dev/block/mmcblk0p7"

6.- What is CID unlock and why do I need it ??

HTC uses CID lock to secure their phones.

The CID, or "Carrier ID", is a string that identifies carrier and language of your device; it is also contained on RUUs and is used to check that you only flash your device with the right, original ROM from your carrier/region.

CID unlock (aka "SuperCID", similar to Windows Mobile's "HardSPL") allows to flash any official RUU and install any ROM you like: from other regions, debranding, downgrading, etc.

gfree easily does both S-OFF and CID unlock.

7.- What is an "RUU" ??

RUU means "ROM Update Utility". It is a flashing tool.

RUUs are "official" shipped from HTC, they contain the flashing tool and a full firmware in a single package. RUUs are executed from a PC.

8.- What is "Radio" and what is the deal with different "radios" ??

They improve your phone signal, Bluetooth, WiFi and GPS reception, and perhaps battery life.

(Thanks Lennyuk !! you are da stig's radio cousin :D)

The official radios thread is located here

9.- Will "flashing" erase all my info an installed apps ??

- If you are flashing a Kernel, a Radio or a Custom Recovery, NO.

- But if you flash a system or a full firmware ROM, then YES: everything will be wiped off, so be sure to backup your stuff.

There's plenty of backup apps available for download from the Market.

(I use and recommend Titanium Backup, but it needs root :D)

You can also do a NANDroid backup.

10.- Will "flashing" void my warranty ??

Aha !! Good question again...

Anyway if your current stock firmware RUU is already available for download you can always flash it back, or you can backup your current ROM image, save it in your SD card or PC, and restore it later to go back to stock.

Enjoy your Desire Z the EZ-DZ way !! :)

BASIC SKILLS and FLASHING TERMINOLOGY:

FREQUENTLY ASKED QUESTIONS​

1.- What is "Bootloader" ??

The Bootloader is a firmware management tool included on every stock ROM, it lets you reset to factory default, use "Fastboot" to flash official images, or launch the Recovery utility.

From the Bootloader you can also check your S-ON or S-OFF state, your firmware and Radio version, etc.

You don't need root or S-OFF to enter the Bootloader because every HTC phone has it.

2.- How do I enter the Bootloader ??

Power off your phone, then, hold the volume down key and the power key.

(You need to disable "Fast boot" from Settings -> Applications, or remove the battery to really power off the Desire Z. Otherwise, power off will just hybernate the phone, and when restarting you will not be able to enter the Bootloader).

To exit Bootloader you have to remove the battery.

If you have a custom Recovery installed, you can select "Recovery" to go there and rebot the phone from the Recovery menu.

3.- How can I backup my current ROM (firmware) ??

With a NANDroid backup from a custom Recovery.

4.- What is a "custom Recovery" and how to do it ??

A custom Recovery (eg. ClockworkMod, aka CWM or just CM) replaces the original Recovery from your firmware with an enhanced version.

A custom Recovery is better than the stock Recovery because it lets you safely flash unsigned or unofficial ("custom") ROMs, and lets you make full backups of your current whole firmware (memory) image (a NANDroid backup).

5.- How do I install ClockworkMod (CWM) Recovery ??

You need root and S-OFF.

Download ROM Manager from the market, install and open it.

Tap "Flash ClockworkMod Recovery", it will ask "Confirm phone model: HTC G2", tap yes (thanks for the tip stridger !!). When finished, it says "Successfully Flashed ClockworkMod Recovery!"

I recommend rebooting the phone after flashing the Recovery.

Now let's test it:

From ROM Manager, tap "Reboot into Recovery", it will ask "Are you sure you want to reboot into ClockworkMod Recovery?", tap OK.

Inside ClockworkMod Recovery, use the trackpad to navigate and select an item, or the volume buttons to scroll, and power button to go back.

Select "Reboot system now" to exit ClockworkMod.

If ClockworkMod Recovery doesn't start and you see a red triangle with an exclamation mark, flash it again. Sometimes it requires a second flash to work properly.

6.- What is a NANDroid backup ??

A complete system image that can be restored at a later date. It is more than a backup because it includes everything you currently have on your phone's internal memory: Boot, Recovery, System, Data, Cache, etc. It's a snapshot of your whole ROM.

To make a NANDroid backup, go to the "Backup and Restore" option in Clockwork and proceed. A NANDroid backup will be saved to the SD card's ClockworkMod folder.

TIP: Save a copy of your NANDroid backups to your PC. It will be useful if the SD card fails, your phone is stolen, or gets bricked.

7.- How can I restore a NANDroid backup ??

If you can access ClockworkMod Recovery it will be very easy to restore from its menu:

Enter the Bootloader (Vol down + Power), select "Recovery" and you will be redirected to ClockworkMod, from where you can restore your NANDroid backup :)

If you phone is bricked and you can't access the Bootloader, there's still a last chance:

You can try to flash ClockworkMod Recovery to your phone from your PC using an ADB shell and the "Fastboot" command. Tricky, but life saving.

Download the PC-flashable ClockworkMod Recovery image from here and copy it to your Andoird SDK/tools folder.

Then, open an MS-DOS command prompt, connect your phone to the PC, and flash it with this ADB command: fastboot flash recovery recovery-clockwork-2.5.1.2-vision.img

8.- What is ADB ??

ADB is the Android Debug Bridge. It uses linux commands to send instructions to the phone.

You can use ADB commands straight from an MS-DOS prompt or open an ADB shell to type linux commmands.

With ADB you can install apps, remove apps, flash images to your phone, and make many changes, all from your PC.

If you are not familiar with MS-DOS / LINUX commands this can be a bit complicated, so this is for slightly advanced users.

To get an ADB shell setup and running you need to download the Android SDK, add your SKD's path to the environmental variables, and then open an MS-DOS command line box on your Windows PC.

There's a good ADB learning guide here: ADB for noobs

(thanks steviewevie !!)

9.- What is a "Goldcard" ??

A Goldcard is a modified SD card which bypasses HTC's RUU SPL/CID check.

When inserted into your phone, it will let you override HTC's firmware flashing protection.

You can take an old spare SD card you may have laying around and convert it to a Goldcard. Size of the card doesn't matter.

When a Goldcard is inserted into the phone you can flash any official HTC firmware, even if it doesn't match your region (aka "debranding") or is older.

Of course the Goldcard is required inserted into the phone only during the flashing process. You can remove it afterwards.

10.- What is an "MD5 checksum" ??

It is a unique algorithm generated from any file, very useful to confirm a file's integrity after downloading/uploading/copying. It looks like a large alphanumeric number.

Many cookers and developers often offer the MD5 checksum number of their files, so the ROM, Radio or Kernel can be checked after download and before flashing, using any MD5 checksum app/program from a PC or the phone.

I use a free Windows app called winMD5sum to check the integrity of my downloads.

Enjoy your Desire Z the EZ-DZ way !! :cool: