A co-worker just got a 41cx and was interested in the MLDL modules. I never paid enough attention to know much about them and I'm not able to remember all the possibilities to tell him. Can someone here list (or give a link to) what's available, whether new (like Clonix or MLDL2000) or old (like Hepax or W&W), what's needed to put ROM images of the various modules in them, URLs for the modern ones, pros and cons for different applications, what they can and cannot do (for example, can they do the paging of the Advantage?), whether a card-reader shell or module shell is needed, whether kit or complete product, and any other important information. Depending on what we find out, I might want to get one too. Thanks to double modules, I have six modules plugged into my four ports; but I might like to add a couple more plus larger file memory. Thanks.


From the top of my head:

MLDL2000 by Meindert Kuipers:

Needs card reader shell or similar housing, stores ROM images in flash or RAM. Very flexible (multiple dip switch selectable configurations, USB connectivity to PC for full control of the RAM and ROM configuration) but adds considerably to the size of the 41. Bank switching (Advantage) and Hepax (on device development) are supported. Battery backup is possible.

Clonix & NoVRAM by Diego Diaz:

Clonix is a flash only ROM emulator which supports bank switching. It fits into a module housing. To flash ROMs you'll need a prommer device (for PICs). Bankswitching is supported.

NoVRAM in its various incarnations adds RAM for Hepax emulation and ROM storage but you still need a prommer. The size is the same. The contents is protected even if you remove the module. So you can use the Hepax file system to transfer programs between machines.

All MLDLs or ROM emulators will eat on your batteries to various degrees. This is somehow firmware dependent. (I'll need to update my devices.) AFAIK none of them can emulate extended memory (but they can hold the EM functions in ROM, of course.)

Edited: 28 May 2009, 5:11 a.m.


As marcus covered all the new mldl's, a quick word to vintage mldl's:

Without exception, they are a)much harder to find, b) much more expensive (recently a hp41cx with built in W&W mldl went for over 2000$ on eBay) and c) less versatile.

For someone starting with mcode, I'd probably recommend a simple NoVram. It has a very attractive price point, and the new USB pic programmers work very well and it uses only one physical port. Also, the HEPAX (and the emulation in the NoVrams) relocate themselves to page 6, saving one page.

For owners of the iPhone/iTouch there is now an even cheaper option - the fantastic i41cx+ program which allows hepax emulation.





and the new USB pic programmers work very well

What is the recommended programmer? Mine is a Windows-only-needs-physical-serial-port type of device which I'd like to replace. If the thing could burn EPROMS as well that would be absolutely great.


Diego offers one on his web-page but you can find it on eBay and other places easily. I never checked if it also does EPROMS but Diego can probably answer that questions.

If works much better than the old Serial programmer, especially as it works with Laptops as well.

I do have a USB burner that (claims to) do EPROMS as well as the Pic-chips but I have never tried it. I can get the name of it if you want.




Thanks Peter, please tell me the name and the price you've paid for it.


Hi Garth,

I'll add just one thing to Marcus excellent summary: get one yourself, it's worth every penny!

Clonix, or NoVRAM are much easier to handle.
MLDL is a Juggernaught - a tad difficult to master.


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