Installing CAS OS on a Nspire CX OS 4.5.1

→ **MyCalcs** profile · by **brocheng** » 27 Oct 2020, 15:26

Hello everyone, I mistakenly upgraded my nspire CX to OS 4.5.1. And I want to use nLoader to install CAS OS on it.
But, I found that the nLoader supports up to OS 4.5 in the tutorial.
So, can I upgrade it to OS 4.5.3, and install Ndless 4.5.3 to install CAS OS according to the tutorial of nLoader ?
Thank you very much for your reply.
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Bonjour à tous, j'ai mis à niveau par erreur mon nspire CX vers OS 4.5.1. Et je veux utiliser nLoader pour installer CAS OS dessus.
Mais, j'ai trouvé que le nLoader prend en charge jusqu'à OS 4.5 dans le didacticiel.
Alors, puis-je le mettre à niveau vers OS 4.5.3 et installer Ndless 4.5.3 pour installer CAS OS conformément au tutoriel de nLoader?
Merci beaucoup pour votre réponse.

→ **MyCalcs** profile · by **critor** » 27 Oct 2020, 15:33

Unfortunately nLoader still hasn't been updated with 4.5.1+ support, and I don't understand why.

You shouldn't update to 4.5.3 or your calculator won't boot anymore.

If you have to update to 4.5.3, you'll have to remove nLoader. You just need to reflash a normal Boot2 image. And of course, no CAS anymore.

→ **MyCalcs** profile · by **brocheng** » 27 Oct 2020, 15:48

critor wrote:Unfortunately nLoader still hasn't been updated with 4.5.1+ support, and I don't understand why.

You shouldn't update to 4.5.3 or your calculator won't boot anymore.

If you have to update to 4.5.3, you'll have to remove nLoader. You just need to reflash a normal Boot2 image. And of course, no CAS anymore.

Thanks for your reply, the only way seems to downgrade my Nspire CX to OS 4.5.0.

Can I use a TTL downloader to downgrade it to OS 4.5.0 ?

→ **MyCalcs** profile · by **critor** » 27 Oct 2020, 16:48

Nothing so complicated in your case. Just :

update to non-CAS OS 4.5.3
install Ndless
then use BtMg or nsNandMgr to remove the downgrade protection
install non-CAS OS 4.5.0
and now proceed with the nLoader installation

→ **MyCalcs** profile · by **brocheng** » 29 Oct 2020, 15:37

critor wrote:Nothing so complicated in your case. Just :
update to non-CAS OS 4.5.3
install Ndless
then use BtMg or nsNandMgr to remove the downgrade protection
install non-CAS OS 4.5.0
and now proceed with the nLoader installation

I have followed your instruction, and everything works fine. My Nspire CX has been installed with CAS OS 4.5.

I really appreciate for your help.