Abstract: A data management method for a long record length memory that is used for data acquisition writes data samples into an initial circular buffer within the memory having a size equal to a pre-trigger time. When a first trigger event occurs, the data samples are then written into a linear region after the circular buffer within the memory. The data sample acquisition in the linear region continues until a post-trigger and new pre-trigger time have elapsed after a last trigger event, at which point the acquisition terminates and the new pre-trigger time becomes a new circular buffer for a next trigger event. In this way all trigger events are captured with associated pre-trigger and post-trigger data.
Type:
Grant
Filed:
March 24, 2006
Date of Patent:
July 7, 2009
Assignee:
Tektronix, Inc.
Inventors:
Terrance R. Beale, Steven K. Sullivan, Kristie L. Veith
Abstract: A transition-density based data timing measurement method uses an estimated transition density (TD) value for an acquired data signal together with edge crossing times to estimate a data period for the acquired data signal. The estimated data period is used for symbol classification to determine a number of bits between adjacent edge crossings, which results are used to adjust the TD value. The adjusted TD value is then used to re-compute the data period.
Abstract: An expanded WIRE-OR Bus structure has a first WIRE-OR Bus arrangement and a second WIRE-OR Bus arrangement. Each of the first and second WIRE-OR Bus arrangements have connected thereto at least one driver element and at least one receiver element. An intelligent bi-directional signal coupling circuit includes a buffer element, a bus arbiter, and a bus driver amplifier. The coupling circuit couples signals between the first WIRE-OR bus and the WIRE-OR second bus, and prevents signals originating on one of the WIRE-OR buses from being coupled back to the same WIRE-OR bus.