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Self-Repairing Computers
Roland Piquepaille writes "Our computers are probably 10,000 times faster than they were twenty years ago. But operating them is much more complex. You all have experienced a PC crash or the disappearance of a large Internet site. What to do to improve the situation? This Scientific American article describes a new method called recovery-oriented computing (ROC). ROC is based on four principles: speedy recovery by using what these researchers call micro-rebooting; using better tools to pinpoint problems in multicomponent systems; build an "undo" function (similar to those in word-processing programs) for large computing systems; and injecting test errors to better evaluate systems and train operators. Check this column for more details or read the long and dense original article if you want to know more."
For a much better, and more detailed, discussion of Recovery Oriented Computing, you're better off visiting the ROC group at Berkeley, specifically David Paterson's writings.
ooooooh! What does this button do? - DeeDee, Dexters Lab.
Well, yeah. That's basically a watchdog timer. It's very common in embedded stuff, because it's cheap to implement - in fact, many microcontrollers have it built into the hardware. In microcontrollers they're very simple - a counter counts up (say) 1024 clock pulses, and if it rolls over then reset the CPU. In normal operation then every time round the main loop you'd write to a specified IO port to kick the watchdog once every millisecond or so - this resets the counter. It's crude but effective, and is very commonly used in things like ECUs for automotive electrickery - although the software is simple enough to be thoroughly tested (BMW 735i's aside) there's still dirty power and mechanically harsh environment to deal with. And your ABS ECU doesn't have , does it?