I understand the basic problem with embedded chips, but would someone please clarify the date problem. Does each chip have its own date? Is that the date when it will cease to function? I keep hearing about how "easy" it will be to fix each one when it shuts down (flash programming?) Please update my very limited knowledge.

Thanks, winna

-- winna (??@??.com), December 21, 1999

Answers

You 'keep hearing how easy it will be to fix each one when it shuts down (flash programming?)'

Sure, maybe using todays technology. Problem is these chips were built before flash memory. The program is built into the circuit board in the form of a prom and the entire chip must be thrown out, and they don't make them anymore, and reverse engineering the chip to too time consuming, and the board is inaccessable, buried deep inside the facility, and anyway, it doesn't use the date function, and besides it is not a mission critical valve.

Stop the winning

-- Winnin Winna (stopthewinnin@theworld.org), December 21, 1999.

The issue is not nearly as easy as they would have you believe. Not all embedded chips can be "flashed". That is, the code is permanently burned into the silicon. The entire chip would have to be replaced in those cases where the code had been tested non-compliant.

The code would be tested as with most other software applications, but if it can't be flashed with new code, or isn't in a socket, the chip must be de-soldered, and a new one soldered in place. Then the system must be tested. This process, for one small chip, could take as little as ten minutes, or as complexity grows, and the number of soldered connections grows, so does the time it takes to replace it. Not to mention the possibility of damaging the circuit board and other components.

The chips often have dates permanently encoded, but those wouldn't normally affect function. They're typically dates of manufacture.

The simple fact is that billions of chips were manufactured non- compliant. Many more billions are compliant. I have heard estimates of up to 500 billion embedded chips total worldwide. If even 0.0001%, a tiny fraction of a percent, were to fail, that could leave 5 million chips useless. Not all of them are in important systems, but some are.

-- Powder (Powder@keg.com), December 21, 1999.