Command Dictionary Report Observe Data
FastScan and FlexTest Reference Manual, V8.6_4 2-347
Report Observe Data
Tools Supported: FastScan
Scope: Atpg, Good, and Fault modes
Prerequisites: You must use the Analyze Observe command prior to this
command.
Usage
REPort OBserve Data [filename] [-Replace]
Description
Displays information from the preceding Analyze Observe command.
The Report Observe Data command displays a summary of the information that
FastScan obtained from the preceding Analyze Observe command.
When the Analyze Observe command fails to detect an output pin for a minimum
number of the random patterns (as defined by the observe threshold), FastScan
identifies the output pin as inadequately observed. For each inadequately-
observed output pin the Analyze Observe command searches for the potential
source of the pin’s observe problem. This it calculates by tracing forward from the
pin through the most difficult-to-observe fanout gate until it reaches a gate which
has no fanout and an observability value less than the threshold.
The Report Observe Data command’s summary report lists up to a maximum of
25 source gates, which, if made observable, would affect a maximum number of
other gates. The command orders the list of gates by the low-observability gates
and includes the low-observability pins, the number of times observed, and the
calculated source gate.
You can write the summary report to a file by specifying a filename.
You use this command primarily when simulating Built-In Self Test (BIST)
circuitry.