HISTORY Command

Saves simulation event history to interface with post-simulation display and analysis programs.

Command HISTORY
Abbreviation HI
Category Output & Monitoring

Function

The HISTORY command is used to save simulation event history to inter-face with post-simulation display and analysis programs. Two history files are created; the general history file and the sequential history file. Their default extensions are hig and his respectively. By default, history files are not created.

Usage

The HISTORY command is described in History Files.

The HISTORY command can be restricted to a specified interval of tests, for patterns, or time, for waveforms, with the PRANGE keyword option:

HISTORY PRANGE=<prange spec>

Specifying File Name

The FILE keyword option is used to specify the filename components of the two history files. The command:

HISTORY FILE:

assigns the default file, while the command:

HISTORY FILE=<file name>

assigns a file name explicitly. Note: no file extension should be specified in this form of the command.

Specifying Signals To Trace

The LIST keyword selects the signals for which events are to be saved. History file creation is enabled by this selection. The signals specified with this keyword are subject to name-based filtering (see STRING keyword option below); only unfiltered signals are accepted for history trace. The command:

HISTORY LIST:

selects all unfiltered signals, while the command:

HISTORY LIST=<signals>

selects all signals in the specified list that are unfiltered.

The NO prefix can be used to selectively remove signals. Signals specified with the NO prefix are not filtered. For example, the sequence of commands:

HISTORY LIST:

NO HISTORY LIST=abc

causes all unfiltered signals to be traced except signal abc.

Specifying A Dump Interval

Once enabled, history dumps (snapshots) are performed every 100 test steps (by default). This default can be changed with the command:

HISTORY PSTEP=<integer>

where <integer> is the test interval to perform the dumps. History dumps can be disabled with the command:

NO HISTORY PSTEP:

Name-Based Filtering

The STRING keyword may be used to systematically filter signals from subsequent HISTORY LIST specifications.

Filtering based on the name of the part generating each signal can be specified with one of two complementary options. The command:

NO HISTORY STRING=&NUMERIC

will cause any signals generated by a part whose lowest-level name component is purely numeric (e.g., a.b.c.153) to be filtered. Alternatively, the command:

NO HISTORY STRING=&ALPHANUMERIC

will cause any signals generated by a part whose lowest-level name component is not a pure numeric (e.g., a.b.c.d12) to be filtered.

Filtering based on the signal's hierarchical name can be specified with the command:

NO HISTORY STRING=<filter string>

where <filter string> is a pattern of characters, possibly enclosed in quotes.

For example, the command:

NO HISTORY STRING="#"

will filter all signals in subsequent HISTORY LIST specifications whose names contain the character "#".

The general form of signal-name based filtering is:

NO HISTORY STRING= <integer>*<filter string>

where <integer> specifies a filter string repetition factor. For example:

NO HISTORY STRING=2*"."

causes all signals at a hierarchical level of three or higher (their names containing at least 2 dots) to be filtered from subsequent HISTORY LIST specifications.

Using the STRING keyword without the NO prefix removes a filter. The command:

HISTORY STRING="#"

causes subsequently specified signals containing "#" in their names to be traced.