The VBT100 (VME Backplane Tester) plugs into a VME or VME64x backplane and performs a series of tests that verify the integrity and safe operation of the backplane. These tests check for intrusive voltages, correct power supply voltages, signal shorts / opens and proper impedance. The tester is a single plug-in 6U VME board that operates in both empty and fully loaded backplanes with or without power.
The VBT100 has been designed to withstand and measure excessive voltages on both signal and power supply pins. This capability allows it to operate in faulty backplanes that could damage other boards. The tester also detects, measures and identifies which signals have excessive voltages so they can be repaired before boards are loaded into a backplane.
Other tests verify that the backplane is within specification insuring other VME boards will operate properly. The VBT100 continually monitors and measures the power supply voltages and displays out of range conditions. A short test checks all signals for shorts to other signals, power and ground. An open test verifies the proper connection of bussed signals. This test also checks for proper backplane terminations and identifies missing pullup and pulldown resistors. Impedance testing detects high and low impedance conditions that could effect backplane operation.
The front panel display and control switches allow the VBT100 to operate as a self contained unit. All tests are initiated by toggling a front panel test switch. The test results are stored in a buffer and displayed on the 24 character alphanumeric LED readout controlled by a scroll pushbutton. During testing information regarding the progress of a test is also displayed.
