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HP Forum Archive 16

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How to know if my 41CV is realy a CV and not a C
Message #1 Posted by Pedro J. Arias on 22 May 2006, 12:54 p.m.

I have bought a 41CV but I am not sure if it is a CV or a C. When I press PRGM screen says 00 REG 46. Is that the usual for a 41CV or not. In addition if I remove the lateral little port at the right side, no contacts or pins and so on are visible, I can see only plastic. Is that the usual?. Thanks for someboy to respond to me ASAP.

Regards, Pedro

      
Re: How to know if my 41CV is realy a CV and not a C
Message #2 Posted by Vassilis Prevelakis on 22 May 2006, 1:15 p.m.,
in response to message #1 by Pedro J. Arias

 Pedro J. Arias wrote:
> When I press PRGM screen says 00 REG 46. 

This just shows the free memory allocated for programs. Assuming you do not care about the programs or data in your calc, you can clear all memory (turn calc off and then turn it back on while pressing the <- key), and do a SIZE 100. If this works and there are no memory modules [1] attached to the calc, you have a CV. If it fails, you have a C.

If you want to preserve memory, do a CAT 1, noting the sizes reported next to each END statement and add them to the 46 you have available. This is the entire program memory. If it is > 64 you have a CV, if not, do a RCL 99 to see if memory has been assigned to registers. If this succeds, you have a 41CV.

BTW the "lateral port" just provides access to the battery compartment, and unless you have a really early model you should not see any contacts there. If you have the rechargable battery pack this port allows you to plug in the charger while the pack is inserted in the calc.

**vp

[1] memory or quad memory should not be connected to a CV anyway, but having X-memory modules is OK and does not affect this procedure.

Edited: 22 May 2006, 1:19 p.m.

            
Re: How to know if my 41CV is realy a CV and not a C
Message #3 Posted by Pedro J. Arias on 22 May 2006, 1:29 p.m.,
in response to message #2 by Vassilis Prevelakis

Thanks a lot after doing SIZE 100 and after PRGM screen says 00 REG 219, so I think is a CV. Is that right?

Thanks once again

                  
Re: How to know if my 41CV is realy a CV and not a C
Message #4 Posted by Thomas Okken on 22 May 2006, 6:42 p.m.,
in response to message #3 by Pedro J. Arias

Yes, 319 registers (SIZE 100 + 219 program registers in your case) is the correct number for an HP-41CV. (Actually it has 320 registers, but the permanent .END. instruction consumes 3 bytes, so there are only 319 "free" registers).

- Thomas


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