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HP Forum Archive 15

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hp41cx auto power off wake up problem
Message #1 Posted by fulcrum on 21 May 2005, 8:57 a.m.

Hello, I have a hp41cx and when it auto powers off I am unable to restart it normally, I have either to remove the batteries and pu them in again and turn it on or push alot of keys and finally it starts after a while trying. How can I solve this? Thank you

      
Re: hp41cx auto power off wake up problem
Message #2 Posted by Vieira, Luiz C. (Brazil) on 21 May 2005, 10:34 a.m.,
in response to message #1 by fulcrum

Hi, Fulcrum;

Although I tend to think of hardware causes, are there any ROM modules attached to it? If so, have you tested if it happens without them? I'm asking about these because I have an HP41CV that used to be hard getting back to life if left resting for some time. The problem was the batteries contacts.

If SW related problems, are there any scheduled activities? I mean, any programmed alarms? Have you tried a master clear as well ([ON]/[<-])?

Not too much of a help, but maybe you cantry some of these.

Success!

Luiz (Brazil)

            
Re: hp41cx auto power off wake up problem
Message #3 Posted by Fulcrum on 21 May 2005, 12:02 p.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

Thank you very much, Luiz, I have three modules installed, Novram, double x-mem, advantage, I am trying to do a master clear but seems I cant do it how can I press [on] [<-] if the calculator turns off? Thank you

                  
Re: hp41cx auto power off wake up problem
Message #4 Posted by Raymond Del Tondo on 21 May 2005, 3:23 p.m.,
in response to message #3 by Fulcrum

So we seem to have found the one which causes your calc to hang.
AFAIR the Clonix/NoVRAM documentation says that the
10 minute timeout event isn't caught by the NoVRAM firmware so far.

Please take a look there.

Diego Diaz can tell you some more specific details.

Raymond

                        
Re: hp41cx auto power off wake up problem
Message #5 Posted by fulcrum on 21 May 2005, 7:04 p.m.,
in response to message #4 by Raymond Del Tondo

Helo, Raymond and Luiz I have tried with all modules to restart after an auto power off, and is the double xmem module which has the issue, as with the novram the calculator resumes ok. I think I will change it by two xmemory modules... Regards

                  
Re: hp41cx auto power off wake up problem
Message #6 Posted by Vieira, Luiz C. (Brazil) on 21 May 2005, 11:41 p.m.,
in response to message #3 by Fulcrum

Hi, Fulcrum;

I'm glad you could find a solution; that's good news! Now, just to add some info about the master clear:

1-with the HP41 turned off, press and hold the back-arrow key;
2-while holding the back-arrow key, turn the calculator on; (notice that the display remains empty)
3-release the back-arrow key.

If everything goes fine, you should see

[MEMORY LOST]
in the display.

Best regards.

Luiz (Brazil)

Edited: 21 May 2005, 11:49 p.m.

                        
Re: hp41cx auto power off wake up problem
Message #7 Posted by Fulcrum on 22 May 2005, 5:31 a.m.,
in response to message #6 by Vieira, Luiz C. (Brazil)

It is so nice to be part of this forum... Thank you!

                              
Re: hp41cx auto power off wake up problem
Message #8 Posted by fulcrum on 22 May 2005, 5:39 a.m.,
in response to message #7 by Fulcrum

Hey, after a hard reset the calculator resumes ok with the modules connected! You were right Luiz, regards

                                    
Re: hp41cx auto power off wake up problem
Message #9 Posted by Diego Diaz on 22 May 2005, 10:34 a.m.,
in response to message #8 by fulcrum

Hi,

This is quite surprising, NoVRAM modules don't handle the power control signals required to overcome an AUTO POWER OFF situation under some circumstances.

- 1st NoVRAM is configured as an Advanced HEPAX.

- 2nd HEPAX page is mapped into an even page.

This is by no means harmful to your calculator nor the contents of its memory. A simple workaround consists in unplugging and reinsert the NoVRAM module, after that you can switch your calculator ON normally.

When used on a C or CV, HEPAX will place itself in page #5, unless you've got a TIME module inserted.

On a CX, TIME is standard in page #5, so HEPAX usualy goes to page #6 where the problem arises.

So, regardless the functionality of the Dbl. X-MEM (which can of course be faulty), I'd like to know if your NoVRAM is configured as Avd. HEPAX and, if so, confirm the tests on your CX, whith the NoVRAM module only.

Let us kown of the result please.

Cheers

Diego.

                                          
Re: hp41cx auto power off wake up problem
Message #10 Posted by fulcrum on 22 May 2005, 3:12 p.m.,
in response to message #9 by Diego Diaz

Diego, I have the novram configured in advanced hepax, and after the hard reset, all modules resume ok with on key. I have novram with ppc rom and hepax flashed in port 1, double x-memory in port 2 and advantage in port 4. Port 3 is empty and is a hp41cx. I repeat, all works ok and resumes well, no faulty modules. Un saludo desde Madrid!

                                    
Good news, indeed! d8^)
Message #11 Posted by Vieira, Luiz C. (Brazil) on 22 May 2005, 12:12 p.m.,
in response to message #8 by fulcrum

Hi Fulcrum, guys;

in some cases, the most exotic behavior in the HP41 (beeping for each/any keystroke, no auto shut-off, amongst others) ususally disapears after the 'memory clear' procedure. I cannot find a single explanation, I just think of main processor register/flags with 'not allowed' contents or state.

Best regards and good luck with your HP41 system!

Luiz (Brazil)

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