Reverse engineering old C-MAP cartridge?

[szigi]

Hi,

I was wondering if there is any information on the pinout and data format of the really old CF-85 type C-MAP cartridge? I have an old Raymarine plotter, which uses this card. I'm not using the plotter for cartography (I'm sailing inland, and there never was a map for this area from c-map), just to display all kind of nav data in the cockpit, but if there were a way to create a map (via some flash + micro-controller cartridge emulator) for my area, I could zoom in to see tracks in larger scale (otherwise it won't let me zoom in more on the basemap).
Is this a far fetched idea?
I know I could get a new plotter, or ipad, but I'm more for the hacking challenge :-)