Well, this page
http://www.nhtsa.dot.gov/cars/problems/studies/record/chidester.htm says the
following (along with other technical details):
"When 150 msec have elapsed from algorithm enable, the data stored in RAM
are transferred to the EEPROM. It requires about 0.7 sec to permanently
record all information. Once a deployment record is written the data are
frozen in EEPROM and cannot be erased, altered, or cleared by service or
crash investigation personnel."
That doesn't necessarily mean that the data can't be altered by low-level
access to the circuitry, unless they are using a special EEPROM chip which
can be permanently write-protected, which they may well be.
Robert Hancock Saskatoon, SK, Canada
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