I have an HP Prime that has been giving me the following problem for a few months:
It often crashes and only lets me type one number.When this is written I cannot delete it or press any other key.Only On and Shift seem to work, although not always.When the calculator enters this state, the only way I have to fix it is by pressing the Reset button on the back of the calculator, and despite being fixed, it does not take more than 1 month for the problem to recur.
I attach a video for a better understanding of the problem.
Unfortunately, there are certain bugs in the calculator (especially in the CAS) that can cause the calculator to be in an invalid state, where some internal data structures are screwed up. I've seen some pretty strange behaviour, including error messages in Chinese. These appear to be caused by insufficient argument checking in the CAS functions.
If this is the cause of the problem, the solution is to reset using ON-Symb; this appears to reset whatever data structures are broken.
Hope this helps.
Jurjen Bos Calculator nerd since 1980. Cryptographer by profession.