I'm opening a topic to list 1.x downgrade problems with TI-Nspire TouchPad, as I've had something frightening yesterday.

Feel free to contribute.


#1:
Calculator: TI-Nspire CAS TouchPad
OSes: 1.6 & 1.7
Problem: The OS doesn't start with any of the 4 available keypads (TouchPad, TouchPad CAS, ClickPad, and 84+). We either get a keyboard error dialog box, either continuous reboots.


#2:
Calculator: TI-Nspire TouchPad basic
OSes: 1.1-1.7
Problem: The OS doesn't start with the TouchPad keypad (continuous reboots).

#3:
Calculator:  TI-Nspire CAS TouchPad
OSes: 1.1-1.4
Problem: The TouchPad keypad keys are mixed and the arrow keys don't work at all.


#4:
Calculator: TI-Nspire CAS TouchPad
OS: 1.4
Problem: When plugging a mini-USB A plug into the Nspire (even if the cable is not connected to anything else) a dialog box is triggered saying that the connected USB peripheral is not working properly, asking to disconnect and reconnect the peripheral, and saying that the hardware might be faulty if the problem does persist.
When validated, the dialog box is triggered again allmost immediatly.
Moreover a strange alternative but regular noise could be heard from inside the USB connector; something like: noise for 1second, silence for 1 second, noise for 1 second...
It does not happen with a mini-USB B plug, and the TI-Nspire seems to be able to communicate properly with that plug.
A reboot didn't correct the problem.
After reupgrading to 2.0, the problem disappeared.

Here's a beta of Norse.
The manual decoder is included.

Should be very close to the final release, which will include the source code and the readme.


Have fun.

And the boot1 rom can't be erased, or can it?

According to some diagnostic strings quoted above, it seems that it is possible for the diagnostic software to reprogram the boot1.

Though it would be unlikely you would need to do that, remember, the nspire has 32mb of RAM, for TI's bloated OS

If I am correct, 32Mb of ROM, and 16Mb of RAM.

Not a problem.


Here's an animated GIF I've posted here in july when we discovered all this.
You can see all SD/Flash related menus and screens.

Of course, everything is failing...




Seems the diagnostic software can even update itself, by looking for its replacement code on the external SD card...

So it can flash everything:
- NAND ROM (boot1)
- NOR ROM (boot2 + diagnostic + OS)

- NOR ROM (boot1)
- NAND ROM (boot2 + diagnostic + OS)

I kinda got worried personally that it was unused Nucleus code that TI didn't remove.

The presence of flashing code in the diagnostic software (which is specific to the Nspire hardware) seems to prove the contrary. That flashing code was not forgotten but added.

Wonderfull Goplat!

I'm dreaming of seeing a photo of the TI-Nspire external SD card reader.


Do you think it is possible for us to build one?
I guess the data is being exchanged through the bottom connector, as there is no usb support at boot1 level (diagnostic software).