By Dwight Bues, EE Times Guru
The 1980s were the halcyon days of circuit board design. In the days before Gate Arrays were inexpensively available with sufficient gate counts to completely implement the desired functionality, many manufacturers were producing ICs that implemented functional blocks that could be included in widely varied designs.
Since I was employed designing VME Bus circuit boards at that time, I recall having great flexibility in implementing my designs.Enter the engineer whom we called “Mr. VVI” behind his back.Incidentally, VVI stands for Vanished Vendor Item.A VVI is a device that, although you verified its availability with the vendor, they either never actually did produce or unexpectedly cancelled.
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