Keying devices for modular systems

摘要

A computer module/module chassis system is provided with a keying system having a binomial design having 2X keying arrangements where X is the number of bits or keying elements in the keying system. The keying system is especially useful in preventing misinstallation of a module in a slot having an incompatible electrical connection system. The usefulness of this keying system is enhanced by the fact that it can be installed late in the manufacturing process or at an installation site.