HP 15C Memory Allocation

[Bill Balme]

I'm at my wit's end! Is my beloved 15C finally broken?
Everything seems to work fine - but I seem to have lost all memory. I can only store numbers in Registers 0 and 1. I have no programming steps available.
If I try 19 f[DIM][(i)] I get Error 10

All the diagnostics [ON]X, [ON]+ and [ON]divide work and show no issue.
All the keystroke functions work fine.

I just can't do any programming.

Please email any thoughts/advise...

Thanks,

Bill

[Randy]

You didn't say if you cleared memory: [ON] [-] like the other self tests. That should result in a "Pr Error" display.

That usually takes care of wierd Voyager behavior.

[Bill Balme]

Randy - you are my hero!
Memory restored - all with a couple of button pushes. Many thanks.

Bill

[Vieira, Luiz C. (Brazil)]

Hi Bill, all;

This sort of behavior only happens when

0 [f][DIM][(i)]

is performed. Registers Ro and R1 in the HP15C are permanent, can never be used with other purposes but store numbers. In fact, they are used as index to access matrix elements.

Beacause

19 [f][DIM][(i)]

did not work, I'd suggest two keystroke sequences that might probably solved the problem. The first one would be

[f][MATRIX]0

that clears all matrix definitions (dimension 0,0) and data, restoring all registers dedicated to matrices to the 'uncommited register segment'. After that, any register that could be used by matrices would be free for use by programs, though. The other one would be considering the existence of programs and clearing program memory with

[f]CLEAR[PRGM] (while in program mode)

In both cases, Randy´s precise solution works perfectly fine because all memory is cleared and default status is set. I decided to add this brief because sometimes, even when the problem is solved, the cause may be yet obscure. As I am an Engineer, I am always trying to find the cause so it can be avoided in the future...

Cheers.

Luiz (Brazil)

Edited: 24 Feb 2006, 12:10 p.m.