Circuit Allowing Card Hot Plugging and Unplugging
Original Publication Date: 1988-Nov-01
Included in the Prior Art Database: 2005-Feb-15
This article describes a circuit to be used in a communication controller allowing line interface cards to be plugged and unplugged without disturbing the other lines of the line scanner when operational. The circuit provides a temporary reset pulse to the logic circuitry on the card, and the frame inbound lead is blocked to avoid glitches or disturbances on the other lines until all the voltages are properly supplied to the card. (Image Omitted) The circuit is provided on each line interface card LIC connected to a line scanner through a multiplex card MUX which arranges the information from the lines into slots in a succession of frames making a superframe. Different length tabs are used in the LIC card connector for the various power supplies (ground, +5 volts and +8.