Ti Nspire CX wont boot

→ **MyCalcs** profile · by **champsilver** » 29 Dec 2019, 23:28

Hello,

i followed the tutorials and installed a CAS OS on my nSpire CS now it starts and shows the warning that CAS Software is installed but it wont boot further. It shows a X in a Red Dot.

I neither can boot in any menu from here. What to do ?

→ **MyCalcs** profile · by **critor** » 29 Dec 2019, 23:54

Hi.

The red X usually means you did select a wrong file when building your nLoader image on the calculator.

Try to :

hold the keys
without releasing them, press and release the reset button on the back
if the calculator didn't turn back on automatically, still without releasing the 3 keys, type the key, twice in a row if necessary

→ **MyCalcs** profile · by **champsilver** » 29 Dec 2019, 23:59

Hey, thanks for the fast reply, i really am in need of your competen support rn

I did that, holding the buttons while restarting, it boots and than shows the same red X again ..

→ **MyCalcs** profile · by **critor** » 30 Dec 2019, 00:10

Thanks.

Assuming you did accurately follow this tutorial, that combo should have made your calculator ignore nLoader and boot normally on its emergency Boot2 copy.

Maybe you can try again ? It's a little tricky. If for example you hold a 4th key by mistake, release the keys before the calculator screen turns back on, or hold

instead of

, it won't work.

If it still doesn't work, then I'm sorry but there is no software-only way of repairing your calculator.

The only way will be to buy a cheap USB-TTL interface and connect it to the dock connector like this to reflash the Boot2 :

→ **MyCalcs** profile · by **champsilver** » 30 Dec 2019, 00:13

Okey, i think i need to reflash the Boot2..

Can i buy any USB-TTL interface ? And is there a tutorial for doing that ?

→ **MyCalcs** profile · by **critor** » 30 Dec 2019, 00:36

No specific tutorial, but we can help and provide you the right informations when needed.

Any USB-TTL interface should be compatible. So the only important thing is the connections.
I used to proceed like this :

→ **MyCalcs** profile · by **champsilver** » 30 Dec 2019, 00:40

Ok, so im gonna order an USB-TTL and get back to you asap. Do i need to open the back cover of the Device or is it enough if i just adjust the cables ?

Thanks alot already

→ **MyCalcs** profile · by **critor** » 30 Dec 2019, 00:48

It's possible without opening anything, by just adjusting and securing the 3 needed cables.
Any of the 2 ground contacts is ok, you don't need to connect both.

→ **MyCalcs** profile · by **champsilver** » 30 Dec 2019, 00:56

This one should work, shouldnt it ?

→ **MyCalcs** profile · by **critor** » 30 Dec 2019, 00:59

Yes, it should work by just connecting the TXD, RXD and GND pins.

But note it's going to be difficult to connect them to the dock connector with the provided female-to-female cables. So unless you have some other cables...