To: Roleigh Martin who wrote (33 ) 2/1/1998 1:02:00 AM From: C.K. Houston Respond to
TYPES OF EMBEDDED FAILURE I am adding to the good info Roleigh provided - DAVE HALL Roleigh #1: Message 3255685 Roleigh #2: Message 3304930 ONE The emebdded system does not have to be "date aware" to get messed up by dates. Note that many embedded systems constantly check each other to ensure no "gross control errors" are present in the control loops. We have seen a couple of year 2000 tests that caused two separate microprocessors to default to different dates. One microprocessor, in its check routine, noted the difference in dates as a "gross control error" and shut the system down. As it was designed to do. It just so happened that the original designers and programmers did not anticipate the date switch, so the embedded sytem did not either. IMPLEMENTATION COMPLIANCE means that all parts of a system receives the data/information that it expects to receive when it expects to receive it. With year 2000, that expectation (assumption) is filled with risk. TWO: If your system is centralized, then much of its operation depends upon control signals sent from a central control microprocessor. If that central M/P has date problems, then it may send out erroneous signals/commands to your instruments (instruments that could care less about the date). This will shut down an entire system easily. Has your engineer done total system tests? If not, why not? THREE: The older microprocessors, 286's and below, will NOT handle date transition at all. They default to 1980 whenever the power is turned off. Such M/P require manual date changes every time they are booted up. Does your embedded system use the older M/P? If so, will the automatic transition to 1980 mess up the O/S or any application that is running, even if the system does not care about dates? Hardware flaws have messed up numerous embedded systems, and Year 2000 is a definite hardware flaw in X86 chips. The main thing to ask people is do they want to bet their jobs, their freedom (from legal problems), and their wealth on there NOT being a Year 2000 problem in their embedded systems? Many people have found numerous problems in places where there should not be any. No place/system seems safe. So check, it's the least you should do. Dave Hall Opinions are my own and not those of my employer Message 3312881
