Basic questions about Clonix41 & Nov32/64?


Hi all,

Have recently visited Diego's Clonix41 site as the product sounds interesting but am confused about it's purpose/range of functions & how it overlaps with the Nov-32/64 modules :(? . A simple explanation would be much appreciated as it sounds like a benficial add on to my HP41CX.




Hi, Micheal,

Except for one word, the Clonix has only flash memory. With memory that requires a burner to be changed, you can use the vast majority of the modules out there that think the ROM address space on the 41C is - well - ROM. What the NoV32 and NoV64 give you is 32K and 64K respectively of static RAM. This allows you to run all of the modules the Clonix will run, but also the "MLDL" setups, which treat part of the 41C's ROM address space as RAM. These systems allowed development of mcode programs right on the calculator.



Howard, I don't have a Clonix (only NoVRAM and NoV-32) but Diego's spec sheet says that Clonix has 512 words of RAM. At time of programming these 512 words can be addressed at F000. Not much, but enough to put in a few user code programs or M-Code functions. Those specs may be old, but when I communicated with Diego last year I thought they were still correct.


Reading the Clonix41 manual, I see that you are correct. I only own Nov-32 and NoV-64, so I have no direct experience with Clonix41. I thought the bank switch port at x4100 was the only writable memory on a Clonix41. Of course, that's wrong in another way too: the Clonix41 doesn't have this memory mapped register, since there are no banks to switch.

Thanks for clearing that up.



CLONIX41: 24K ROM (6*4K HP-41 ROM images). You burn this with a burner from your PC.

NoVRAM: 8K ROM (2*4K ROM images) + 16K HEPAX RAM (you can save programs to this RAM and run them from this RAM space. You can also save XM-files and the whole calculator RAM. Or you can save ROM images into this RAM [rather useless as this would be the same as the Clonix41, only the Clonix is cheaper]. And, you can use the HEPAX RAM to create your own MCODE programs (!))

NoV-32: 8K ROM + 32K HEPAX RAM (divided into two blocks of 16K each where only one block is accessible at a time. You choose which block to access by writing the WORD "0" or "1" into the address 4100h [see the HEPAX manual for doing this via the function HEXEDIT or do it via the ICEBOX ROM which would then have to be one of the 4K ROM images]).

NoV-64: 2*8K ROM (two blocks, one accessible at a time) + 64K HEPAX RAM (four blocks of 16K, one accessible at a time). Use HEXEDIT or ICEBOX ROM to switch between the various ROM and RAM blocks: In address 4100h, write the WORD x0y where x is the ROM block to activate ["0" means no active block/no ROM, "1" means first 8K ROM block active, "2" means second block] - y means which RAM block to activate: "0", "1", "2" or "3".

CLONIX-D: 2*24K ROM images in two block. The active block depends on which port you plug the module into (really cool).




Thanks Howard & Geir, your explanations were very helpful. I take it the software for "burning" to Rom & setting RAM functions comes with the product?




Yes indeed.

Go get it! It's the best add-on for your 41 ever.



One question: how much power do these modules use?

HEPAX can be power hungry, drainig betteries rather quickly, son I am curious.



From what I can see; just slightly more drain while in sleep or standby, but around 4x drain on actual run. In practice; Not a problem, use rechargeable batteries.


Diego has the power usage specs for Clonix on his web site. Based on the RAM that is used for the NoVram versions, there should not be any additional power consumed, except during writes into that memory.

Sleep (HP-41 turned off) 10 micro-Amps

Standby (HP-41 on, but just sitting there, doing nothing) 100 micro-Amps

Run (HP-41 running a program) 13.5 milli-Amps


Gier, some corrections are in order:

NoVRAM has 24K of Flash ROM, just like Clonix. In the standard configuration (HEPAX emulation) 16K is used for the HEPAX code, and the other 8K is avaiable to use as another ROM.

NoV-32 - Same 24K of Flash ROM.

NoV-64 - Has 48K of Flash ROM. 16K for HEPAX ROM, 16K in block 1 ROM, and 16K in block 2 ROM. (I really need to get one of those!)



Correct. I didn't include the HEPAX ROM in my post.

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