@sheepdoll: Not sure if there is really a free PCB tool as one has to get the board made somehow.
I've been looking at that http://www.123dapp.com/circuits tool/site -- you can use a virtual breadboard and/or schematic to capture your design for an Arduino shield -- then use the real-time mixed-signal simulator to check how th ehardware works with your sketch -- then move into their PCB layout package to lay out the board -- all for free -- but as you say, you then have to pay to get the board built...
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used in Orion Spacecraft, part of NASA's Mars mission. Live radio show and live chat. Get your questions ready.
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