possible hboot downgrade

[Guest yueh]

Hi,

Basically I've rooted my desire, flashed defrost 0.7 to test froyo and after that tried to unroot it again.

When i noticed that the recovery mode shows hboot 0.75 after unrooting it, but i don't had enough time to reproduce it.

Would be nice if someone, possible with more experience than me, could also try it.

Phone Informations

- unbranded Desire

- updated to 1.21 and hboot 0.8 before rooting

Steps to test froyo

- used the rooting guide from modaco

- flashed defrost on it

As froyo/defrost is bit unstable, I decided to flash it back to 2.1 including unrooting it in the process.

It was not possible to use the RUU directly.

So I tried some additional steps.

Steps to unroot

- flashed MCR without additions

- still not possible with the RUU to unroot it

- used the guide here to change version to 1.15.405.1 (german, translation at the bottom)

- now it was possible to flash the Europe 1.15.405.1 RUU to it

- by luck checked the recovery and it showed hboot 0.75

Basic Translation

1. Tools needed:

1.1. Hex editor

1.2. rooted desire

1.3. misc.img

1.4. attachment flash_image.zip (in german guide)

2. creating misc.img

2.1. connect the desire to your pc and start a adb shell with:

----> adb shell

2.2. copy mtd0 to sdcard as misc.img

----> cat /dev/mtd/mtd0 > /sdcard/misc.img

3. edit misc.img

3.1. copy misc.img to your pc (or edit it directly on sdcard)

3.2. start a hex editor and open misc.img

3.3. in line 11 is the current version (example: 1.21.405.1)

3.4. change it to 1.15.405.1

3.5. save under a new name and copy it to sdcard

4. flash modified misc.img

4.1. download flash_image.zip, unzip and copy the content to the sdcard (attachment in german guide)

4.2. move via adb to the sdcard

----> cat /sdcard/flash_image > /data/flash_image

4.3. add execute bit

----> chmod 755 /data/flash_image

4.4. flash the modified image (don't forget to change name)

----> /data/flash_image misc /sdcard/misc-mod.img

(4.5. could need more than one try, seems there is no output on success)

[Guest EddyOS]

So you're saying you CAN downgrade the HBOOT?

Edited June 10, 2010 by EddyOS

[Guest yueh]

Yes, but as I said, i did not try it a second time to be sure.

Or even how it work and under which conditions.

[Guest aslsthlm]

Interesting, does´t work, anybody else who has tested it ?

[Guest pina]

lol, today I just noticed the same thing happened to me. I always thought I had bootloader 0.8... but suddenly, after the brick, it's been rooted to bootloader 0.75.

- First, I got 0.75, then my usb bricked.

- Then I unrooted my phone and the utility upgraded my rom and bootloader to 0.80

- After the brick-fix, I rooted my phone again

- In meantime I flashed several times several roms

- Today, I accidantely noticed my bootloader was downgraded to 0.75

I don't know how or when it happened, but I'm sure that something downgraded my bootloader back to 0.75. Maybe the brick-fix did downgrade the bootloader, or the unrooting proces AFTER the fix. I don't know but it should be one of them.

Edited June 10, 2010 by pina

[Guest mountnorth]

Yes, but as I said, i did not try it a second time to be sure.

Or even how it work and under which conditions.

Could you please do a "cat /dev/mtd/mtd0ro > /sdcard/misc-ro.img" and look which version is there in line 11?

edit: I just tried the procedure but the RUU said I'm at Version 1.21.405.1 although my flashed misc.img definately was at 1.15.405.1 (did cat again after reboot).

edit2: retried, might need a goldcard plugged in cause I get the customer-id error

Edited June 10, 2010 by mountnorth

[Guest yueh]

I'll try to reproduce it this evening at home, got no usb cable here at work.

There were also some quirks while unrooting.

I tried it several times and in some cases the RUU won't reconnected to the bootleader after it restarted the phone.

Reconnecting the usb and restartet the RUU then, resolved the error.

If I remember correctly, the version shows something with "MCR" in the version at the normal RUU update,

while I had to reconnect the usb, it showed the changed version in the misc.img.

Can't also remember if this was the case in my successful unroot.

I think it should be possible to reduce to steps to something like

- root phone

- modify misc.img and flash it back

- start RUU and possible disconnet usb after reboot or kill RUU

- restart RUU to flash a 1.15

I'm 100% sure that it showed hboot 0.75 after the successful unroot.

Edited June 10, 2010 by yueh

[Guest mountnorth]

Before I try further (my phone is 0.80 from O²) I'd like to know if it would be useful for anything or anyone if there is a way to downgrade hboot to .75 on a phone that was delivered with .80.

I have some more ideas to try but if its not of any use I'll not risk bricking my phone :)

[Guest yueh]

I don't really know, what a possible downgrade would offer.

Followed only paul on his progress to get root access and the first try to root is about 2 days ago.

Just want to share this information in case it would be useful

Currently im trying to reproduce it.

Phone as before

- HTC Desire

- 1.21 image

- hboot 0.8

Steps

- rooting as described in the modaco guide

- after this it is version 1.15 with hboot 0.8

- as described before change the version in misc.img to 1.15.405.4 and flashed it

- shutdown it and started into fastboot

- executed "fastboot-windows.exe oem rebootRUU"

- applied the HTC Bravo WWE 1.15.405.4 RUU to unroot it

- now it shows hboot 0.75 in fastboot

It seems that the RUU checks different informations, depending if it is started while the phone runs normaly or in fastboot mode.

[Guest judgey2k10]

lol i just come here to see if there was a way to downgrade it.

Can anyone comfirm plz as im stuck on 0.80 :)

[Guest xTc is loVe]

lol i just come here to see if there was a way to downgrade it.

Can anyone comfirm plz as im stuck on 0.80 :)

With this tut u can downgrade to an older version! Like from 2.1.5 for example to 1.1.7.

U CANT downgrade hboot ;-)

[Guest burst]

- used the guide here to change version to 1.15.405.1 (german, translation at the bottom)

XD love it to see my Guide floating around the World :)

[Guest pina]

U CANT downgrade hboot ;-)

I just told that you CAN downgrade, because I did it! I was on bootloader 0.75 and now on 0.80!

[Guest yabolek]

I just told that you CAN downgrade, because I did it! I was on bootloader 0.75 and now on 0.80!

That is not a downgrade mate :)

[Guest behnaam]

I confirm it working, using a slight different method. Running hboot 0.66 now, it was on 0.75 before. And dont ask me how I got hboot 0.66 :)

[Guest mountnorth]

I confirm it working, using a slight different method. Running hboot 0.66 now, it was on 0.75 before. And dont ask me how I got hboot 0.66 :)

Thanks for confirming and posting your guide, I still might try it with my phone that shipped with 0.80 if I'm in the right mood for it :)

[Guest Nicke]

Do you actually downgrade or are you just changing the numbers reported by the phone?

Edit: Ok, looks like it actually downgrades. Great! :)

Edited June 11, 2010 by Nicke

[Guest ersinjeofizik]

Do you actually downgrade or are you just changing the numbers reported by the phone?

Edit: Ok, looks like it actually downgrades. Great! :P

Works great, any additional informaton needed..

I made it, I flashed 1.15.405.1 and HBOOT Downgraded from 0.80 to 0.75 :)

thanks a lot :D

[Guest Prime-Time]

working nicely, thx for the tutorial.

Now i Can install My official RUU for my singapore Desire