@Crusty: As I generally use Bascom to programme AVR I can run soft I2C or SPI on nearly any pin.
The thing is that a lot of Arduino users are absolute beginners -- they just want to plug the shields in and have them work -- it comes as a big shock to some of them when they upgrade to a Mega and find that 1/2 of their shields no longer work.
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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