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Replace EEPROM with MMC - Can this be done? Too adventurous??

Hi all,

I'm a radio controll modeller. In my hobby we have memory modules for our transmitters to hold model settings. Up until very recently these have all been eeprom based - I've built a few of the simple 16K ones myself. Slowly the manufacturers are going over to SD Cards, but there's still a lot of old school transmitters around.

What I'd like to do is replace the eeprom in the higher capacity modules with an MMC card - I don't know if this is even possible given the size restrictions. I've searched on the web and can't find anything like this. In my mind this would have 3 benefits: Simple backup to a PC, cheaper larger memory, one SD card would be compatible with all your transmitters so you wouldn't have to have memory modules for each one.

Here's an example of one of the larger cards - the maximum size supported by the manufacturer is 64K, hence the need to break it into banks. 64K can be used up pretty fast with a high end transmitter!
http://www.rc-market.com/ultrap_e.php

The I2C based control protocol is proprietary but fairly well understood here's a description
http://sylvain.lichtenberger.perso.sfr.fr/CampacSL.htm
http://www.rcdesign.ru/articles/electronics/mempac64k

What I'm thinking based on my limited knowledge is that you should be able to write a program for a PIC chip which could translate to SPI and pad information before storing it on an SD Card into 'virtual' 64K sections. It would be great to use FAT, but worst case you could easily write a program to read and backup the card at a base level.

I've never had the excuse to buy (or try) a PIC programmer until now. I have some experience in electronics and lots in programming (but all in high level languages like J2ME, C#, Delphi and VB) - would I be overreaching myself with this?
 
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