Hitex have produced a matrix board for prototyping your custom hardware with an mbed module. We have made it very simple with minimal compinents added to keep the cost down. You can see the item on http://mbed.org/cookbook/HitexMatrix We have left off the ethernet connector, the mini usb and the SD card socket but could produce another version with these items populated on it. You can purchase the items yourself and solder them down which is not a difficult task to do, concidering all the routing has been done, however I wonder weather it is more useful to your user to have another variant with the parts pre-populated on it. Any comment on this would be helpfull. This is one of two board we currently supply for mbed development work. The other is the RS-EDP platform. http://mbed.org/cookbook/RS-EDP

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