tkgate man page

tkgate — Tcl/Tk based digital circuit editor and simulator


tkgate [-xqs] [-X script] [-l file] [-p file] [-P printer] [files...]


TkGate is a graphical editor and event driven simulator for digital circuits with a tcl/tk-based interface.  Supported circuit elements include basic gates (AND, OR, etc.), tri-state gates, adders, multipliers, registers, memories and mos transistors.  Hierarchical design is also supported with support for user defined modules.  Save files are based on the Verilog netlist format.

TkGate documentation can be found at:


The options are as follows:

-X script

Automaticaly start the simulator and execute the specified simulation script.

-p file

Print circuit to file without starting GUI.

-P printer

Print circuit to printer without starting GUI.

-l file

Read the specified file as a library.


Automaticaly start the simulator.


Suppress startup messages.


Excute with a synchronous X server connection.  This option is primarily for debugging.

-L lang

Specify a locality to use if tkgate has been configued for Japanese support.  The locality should be either "ASCII" for English, or "ja_JP.EUC" for Japanese. This option can also be set via the LANG environment variable.

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



Jeffery Hansen (

Referenced By

gmac(1), verga(1).