Author Topic: Why is it impossible to downgrade from OS 3.9?  (Read 4379 times)

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Offline northern_snow

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Why is it impossible to downgrade from OS 3.9?
« on: August 19, 2014, 05:13:07 am »
What if I flash the boot2 through TTL?
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Offline Jim Bauwens

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #1 on: August 19, 2014, 05:37:49 am »
As nLaunch works at boot2 level, you might be able to use it (possibly with modifications) to downgrade it I assume. But maybe there is something that I'm not thinking correctly about that would render this impossible.

Offline Vogtinator

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #2 on: August 19, 2014, 06:33:04 pm »
nLaunch works on boot2 3.10.16 only, not higher, and this version of boot2 only works on HW < J.

Offline northern_snow

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #3 on: August 20, 2014, 03:45:58 am »

Well it's confirmed that it's still possible to downgrade OS 3.9. First delete OS, then delete boot2 and flash boot2 through TTL, then use nLaunch to enter OS 3.1 and use the NandManger to delete the minimum OS information.


The full process has been post here:http://scalc.org/forum.php?mod=viewthread&tid=71

Offline Vogtinator

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #4 on: August 20, 2014, 08:24:37 am »
But as I said, only possible on older calcs.

Offline northern_snow

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #5 on: August 21, 2014, 01:27:55 am »
Hmmm you are right. Only possible on HW<J.

Offline DJ Omnimaga

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #6 on: August 21, 2014, 02:44:07 am »
Wait, so it is possible on older CX models after all? I thought it only was possible on non-color models such as the Clickpad and Touchpad. ???

Offline Adriweb

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Re: Why is it impossible to downgrade from OS 3.9?
« Reply #7 on: August 21, 2014, 06:33:05 am »
in any case : on < J models, yes.

If 3.9 is already installed, then you'd need external hardware (to reflash the nlaunchable boot2). If it's < 3.9  then it's easier.
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