Computer bus structure permitting replacement of modules during operation.

摘要

A computer bus structure (20) is provided which permits replacement of removable modules (12, 14) during operation of a computer (10) wherein means are provided to precharge signal output lines to within a predetermined range prior to the usage of the signal output lines (42) to carry signals, and further, wherein means are provided to minimize arcing to pins designed to carry the power and signals of a connector. In a specific embodiment, pin length, i.e., separation between male and female components of the connector, are subdivided into long pin (40) length L and short pin (42) length 5. Ground connections (50) and power connections (46) for each voltage level are assigned to the long pin lengths. Signal connections (84) and a second power connection (52) for each voltage level is assigned to the short pin lengths. The precharge/prebias circuit comprises a resistor divider coupled (92, 94) between a power source (49) and ground (98) with a high impedance tap (95, 82) coupled to a designated signal pin (84), across which is coupled a charging capacitor (90) or equivalent representing the capacitance of the signal line (82). Bias is applied to the precharge/prebias circuit for a sufficient length of time to precharge the signal line (82) to a desired neutral signal level between expected high and low signal values prior to connection of the short pin (84) to its mate.