US 6,389,565 B2 · Mechanism and display for boundary-scan debugging information

Abstract

A graphical user interface for displaying boundary scan test data, and method for producing the same, is presented. The user interface display allows a user to view boundary scan test data from a boundary scan testing device in a format well-suited for debugging. Serial data received from the testing device is organized into a parallel format to display predicted versus actual data values on a per node basis, to show how a node is passing or failing. In a preferred embodiment, the user views the frame cell number in the boundary scan chain, the device cell number within a device at that point of the chain, the device name, the pin of the device associated with the cell, the node associated with the pin, the predicted value for the cell, the actual value for the cell as if differs from the predicted value if it differs, and the cell numbers for drivers that match predicted and actual data. Frame cells can be displayed in numerical or sorted boundary scan chain order, failing status only, or passing status only. The preferred embodiment display has the capability to display interesting correlations in the data to assist the user in debugging the circuit under test, including devices driving at fail, devices receiving at fail, devices driving only passes, devices receiving only passes, nodes always failing, nodes sometimes failing, and nodes always passing.

Claims20

Dependent claims

A system for displaying boundary scan test data generated by a boundary scan testing device, comprising:

a graphical user interface process which receives a data packet, said data packet corresponding to a boundary scan frame and comprising a frame cell identifier, a node identifier, a predicted value, and an actual value, said graphical user interface displaying said frame cell identifier, said node identifier, said predicted value and said actual value, wherein said predicted value and said actual value are aligned in a parallel format that visually alerts a viewer to a match condition or a mis-match condition between said predicted value and said actual value.

A method for displaying boundary scan test data obtained from boundary scan cells of a circuit under test as generated by a boundary scan testing device, comprising:

receiving said boundary scan test data generated by said boundary scan testing device;
extracting a frame cell identifier from said boundary scan test data;
extracting a predicted value associated with said frame cell from said boundary scan test data, said predicted value comprising a prediction of a value associated with a boundary scan cell;
extracting an actual value associated with said frame cell from said boundary scan test data, said actual value comprising a test value associated with said boundary scan cell obtained by said boundary scan test;
extracting a node identifier associated with said predicted value and said actual value from said boundary scan test data;
and
displaying said frame cell identifier, said node identifier, said predicted value and said actual value, wherein said predicted value and said actual value are aligned in a parallel format that visually alerts a viewer to a match condition or a mis-match condition between said predicted value and said actual value.

4 more elements

Dependencies are inferred from the claim text.

Mechanism and display for boundary-scan debugging information

Life of this patent

Mechanism and display for boundary-scan debugging information

Life of this patent

Abstract

Claims20