Test vehicle for selectively inserting diagnostic signals into a bus-connected data-processing system
AssigneeInternational Business Machines Corporation
InventorDelwyn Roche Wheeler, Jr.
Life of this patent
Estimating the term…
Abstract
A test vehicle capable of being interleaved in a bus-connected data-processing system includes two unidirectional transmission units having outputs connected to opposite ones of bus connecting terminals and inputs connected to such terminals. A direction controller in the vehicle controls the transmission of signals through the unidirectional transmission units. Each of the transmission units has means for receiving diagnostic signals from an external source which also controls the directional controller which in turn controls the transmission units. The direction controller further receives signals from the transmission units for controlling transmission of signals therethrough.
Claims11
A test vehicle for a bus-connected data-processing system for selectively interjecting diagnostic signals on the bus via a pair of terminals adapted to be attached to a bus such that bus signals flow through the test vehicle via said terminals and to the exclusion of data processing signals normally on said bus characterized in that a pair of AND circuits are connected respectively to said terminals for receiving data processing signals therefrom, a pair of combining circuits respectively connected to receive signals from said AND circuits and having outputs connected to said terminals respectively not connected to said respective AND circuits, a pair of diagnostic input connections for receiving diagnostic input signals respectively connected to said combining circuits, and a direction controller receiving signals from said AND circuits and having a diagnostic control connection for receiving control signals and having electrical connections to said AND circuits for enabling one and only one of said AND circuits in accordance with signals received by said direction controller.
A test vehicle for a bus-connected data-processing system for selectively interjecting diagnostic signals on a bus via a pair of terminals to the exclusion of data processing signals characterized in that said test vehicle has a right transmission unit and a left transmission unit respectively interconnecting said terminals for transmission of signals in mutually exclusive opposite directions, and
- a direction controller connected to said transmission units for actuating and deactuating same and responsive to signals received from said transmission units for actuating and deactuating said transmission units for limiting signal transmission on said bus to one of said opposite directions.
A data processing test system including a bus-connected data-processing system, said bus having interjecting points located between two physically adjacent electrically connected units, said electrical connection being via said bus,
- a diagnostic unit for supplying control signals and diagnostic signals,
- a test vehicle interjection unit electrically interposed between said interjecting points on said bus and connected to said diagnostic unit for receiving said control signals and said diagnostic signals for selectively transferring said diagnostic signals to said bus, and
- transmission limiting means in said test vehicle for limiting transmissions in one of two directions on said bus whereby signals including said diagnostic signals are limited on the bus for facilitating analysis.
Dependencies are inferred from the claim text.