HP-41CV extended memory


Hi all,

I just picked up a near new 41CV to replace the one I lost about 15 years ago. I loved the calculator then and I still do. Can I extend the memory for a 41cv? If so which HP part # do I need? The manual says you can't but I seem to remember that there was an extended function/memory module for the 41CV.




Jim --

Hello, bro'! About a month ago, I bought a 1986 HP-41CV in near-new condition in order to have one for the first time -- just couldn't afford the $300 as an 18-year-old in 1981.

While the built-in regular main memory is indeed maxed out (319 registers) on the -CV and -CX, you can add to the -CV (and -C) "extended memory" with required "extended functions" using the "X Functions" Pac (ROM module) HP82180A. The "X Memory" Pac (HP82181A) provides additional extended memory. My unit has both these modules (sorry, not for sale!).

Data is stored in this extended memory in the form of files with types "program", "data", and "ASCII". The "X Functions" utilities are used to download information stored in extended memory to main memory for access and use.

The -CX came with built-in functionality of the "X Functions" and Time (HP82182A) Modules and a text editor.

Additional info is available at this MOHPC website


Thanks Karl. I don't need the memory yet but will keep an eye out for the two modules.



Note that you *need* the X-func module to be able
to use the X-mem modules.
The X-func module provides 124 X-mem registers, and
each X-mem module adds another 238, for a maximum of
600 (unless my memory fails me).
(Max might be 620 or something perhaps?)


yep; it's 600 of which 598 are usefull. if you only have one file then two registers are taken up by the header. thats 298 coordinate pairs for a surveyor. i remember when that much memory seemed endless......

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