You should have a look at our live FSM view feature in Sigasi. Sigasi now has an interactive State Machine Viewer that updates while you type your code. You can also click it to navigate back to your source code. This interactivity greatly enhances the advantages you described in your post.
And it even works with unfinished or broken code.
You can watch a screencast at http://www.sigasi.com/screencast/vhdl-state-machine-diagram
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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