Use of Engineering Change Levels for Diagnosing Card Incompatibility Problems
Original Publication Date: 1988-Mar-01
Included in the Prior Art Database: 2005-Feb-14
Encoded Engineering Change (EC) levels, by means of an index level, are etched into electronics cards to provide a mechanism for identifying true card part numbers without the overhead and expense of storing the entire part number on the card or in the unit. When used in conjunction with a base, or original, part number stored within the unit Vital Product Data (VPD), the true part number can be derived when necessary to service the equipment. Index values are etched into each card that requires EC level tracking. The product can then be serviced using the index value on a particular card to determine the 'real' part number. The EC levels are implemented by wiring resistor networks on the electronics card. An example implementation is shown in the figure.