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HP Prime - Reset methods
Message #1 Posted by bluesun08 on 20 Nov 2013, 6:16 p.m.

I read several reset methods:

a) Reset hole (back of the unit)
b) On-Symb key
c) "F,C,O"-Reset
d) Esc+Apps+On
e) Reset(which?) + Backspace

Questions:
1. What are the effects of these particular reset methods?
2. Are there other reset methods?

      
Re: HP Prime - Reset methods
Message #2 Posted by Joe Horn on 21 Nov 2013, 12:15 a.m.,
in response to message #1 by bluesun08

Quote:
I read several reset methods:

a) Reset hole (back of the unit)
b) On-Symb key
c) "F,C,O"-Reset
d) Esc+Apps+On
e) Reset(which?) + Backspace

Questions:
1. What are the effects of these particular reset methods?
2. Are there other reset methods?
Here's my current understanding:

a & b: Simple warmstart, recovers keyboard control, restores most of RAM to the state it was in at the last power-down, thus possibly losing subsequent changes.
c: Displays the EA656 DIAGNOSTIC menu. Mostly used for resetting memory to factory condition ("Format Disk C") by pressing 4, 3, Enter, Esc, 9. This clears EVERYTHING, even the current language setting. (But not the OS & boot loader, obviously!) Many other operations are available in this undocumented diagnostic menu.
d: Clears most of memory, but maintains a few basic things (e.g. calculator name, color theme, language). Same as emulator's "Calculator Reset", or "Clear all memory" in the Memory Manager (which does NOT clear ALL memory).
e: Holding down the backspace key during a warmstart supposedly prevents some things from loading. If the machine crashes immediately upon turn-on, try holding down the backspace key.

Note: The F+C+O reset can be performed several ways, including holding down F+C+O during a warmstart, or simply holding down F+C+O while turning the calculator on.

I don't know of any other reset methods.

      
Re: HP Prime - Reset methods
Message #3 Posted by Alberto Candel on 21 Nov 2013, 1:41 a.m.,
in response to message #1 by bluesun08

Quote:
I read several reset methods:

a) Reset hole (back of the unit)
b) On-Symb key
c) "F,C,O"-Reset
d) Esc+Apps+On
e) Reset(which?) + Backspace

Questions:
1. What are the effects of these particular reset methods?
2. Are there other reset methods?

A difference that I noticed between (a) and (b) was that with (a) I lost everything (variables, Home Cas Functons ...) except my programs. Even the app view was rearranged to factory settings. With (b) I was able to recover everything except for something that may have caused the crash, like a graph, or an item in the input line of CAS or Home.

            
Re: HP Prime - Reset methods
Message #4 Posted by Joe Horn on 21 Nov 2013, 9:49 a.m.,
in response to message #3 by Alberto Candel

Quote:
A difference that I noticed between (a) and (b) was that with (a) I lost everything (variables, Home Cas Functons ...) except my programs. Even the app view was rearranged to factory settings. With (b) I was able to recover everything except for something that may have caused the crash, like a graph, or an item in the input line of CAS or Home.
The difference is not actually between (a) and (b), but a matter of how much you changed in memory between your last power-up and the reset. Every time you turn off the Prime, everything in RAM gets saved in flash. When you perform a warmstart (either by On+Symb or by paperclip), the current contents of RAM get blown away and replaced by whatever was saved in flash. Therefore this won't lose anything if you perform a power cycle before performing the warmstart. On the other hand, if you turn on your Prime, do a lot of work, then perform a warmstart, you'll lose everything you've done since power-up, EXCEPT for things that get saved immediately, like programs, notes, etc.

Here's a good example of this in action:
1. In Home, press Shift Esc (Clear)
2. 1 Enter 2 Enter 3 Enter
3. Turn off and back on (saves RAM to flash)
4. Shift Esc (Clear)
5. 4 Enter 5 Enter 6 Enter
6. On+Symb *or* paperclip reset
7. See 1 2 3 on the stack again, not 4 5 6.


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