As I've noted, software defined peripherals has been done before, by at least Scenix/Ubicomm (bankrupt), Parallax Propellar, and the XMOS chips. If you wanted to stretch a bit, you could include TI's PRU (featured in the BeagleBone) and the Cyprus PSoC's (programmable analog peripherals).
Another comment: parallel programming is still hard, whether it's cooperating virtual Arduinos or cooperating PLC tasks (side story: I recently realized we had some deadlocks in some structured text PLC code involving a couple of separate cooperating programs. It escaped dedication because it doesn't show up under normal circumstances...)
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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