verga man page

verga — VERrilog simulator for tkGAte


verga [-eslqi] [-d dtype] [-S script] [-P mods] [-t mod] [-B dir] [-D hash] [-W wmode] [files...]


Verga is a verilog simulator designed to be used with tkgate, but it can also be used as a stand-alone simulator.

Verga documentation can be found at:


The options are as follows:


Dump the list of error codes and associated messages that can be produced by verga.  This option is primarily for developer purposes.


Scan a Verilog file and output information about its modules and nets.  This option is primarily used internally by tkgate.


Show the verga license.


Run in 'quiet' mode, suppressing extraneous messages.


Run in 'interactive' mode.  This mode is intended primarily for use when verga is being invoked by tkgate.

-d dtype

Type of delays to use.  Can be 'min', 'max' or 'typical'.

-S script

Load simulation scripts for each '-S' switch.

-P mod

Print the named module from the parsed structure for each '-P' specified.

-t mod

Override the default and designate 'mod' as the top-level module.

-B dir

Directory to use as base directory when loading files

-D hash

Delete the input files after loading if 'hash' exactly matches a hash code computed on the file name.  This option should only be used by tkgate which writes the file to simulate to a temporary file before invoking the simulator.

-W wmode

Mode for warning message handling.  Can be 1 for "ignore warnings", 2 for "report warnings only if there were errors", 3 for "always report warnings" or 4 for "always report warnings and stop simulator even if only warnings".

History & Credits

TkGate begin life as an undergraduate project at Carnegie Mellon University (CMU) in 1987.  At that time it was called simply 'gate' and ran under the 'wm' window manager, a windowing system developed at CMU before X11 was widely used.  In this incarnation it was used by students in the computer architecture course at CMU to develop a simple microprocessor (dubbed "The Bat Computer").  After laying dormant for several years, it was resurrected in 1991 and ported to run under X11 with the Xlib API.  In this incarnation it was used several times by students in the introductory digital logic course, but after the author graduated and left CMU, it went into hibernation again.  This Tcl/Tk incarnation was begun in 1998.  While there is certainly some cruftyness in the implementation in places due to the multiple reincarnations, many new features have been added since the older wm and X11 versions, and the interface has been made much easier to use.

See Also

gmac(1), tkgate(1)


Jeffery Hansen (

Referenced By