TkGate 1.8.7 / 2.0a7

TkGate is a event driven digital circuit simulator with a tcl/tk-based graphical editor. TkGate supports a wide range of primitive circuit elements as well as user-defined modules for hierarchical design.
The distribution comes with a number of tutorial and example circuits which can be loaded through the "Help" menu. The example circuits include a simple CPU, programmed to run the Animals game. TkGate is free software provided with source code under the Gnu Public License.
Main features:
Graphical circuit design
- Hierarchical design through user defined modules.
- Easy to use point-and-click user interface.
- Create hyperlinks to move about in circuit or load other files.
- Multi-lingual interface (Catalan, English, French, German, Japanese, Spanish, Welsh)
- Verilog-like save file format.
Logic simulation
- Control through the GUI or through script files.
- Suitable for simulation at transistor, gate or register transfer level.
- Six valued logic model including 0, 1, floating, unknown, "low" and "high".
- Support for custom delay models.
- Graphical display of simulation results.
- Breakpoints, single-step and clock-step simulator control.
- Static critical path analysis.
Primitive circuit elements include:
- Basic gates (AND, OR, etc.)
- Switch-level NMOS and PMOS transistors
- Tristate buffers
- Alu components (Adders, shifters, multipliers)
- Memory elements (Registers, RAMs, ROMs)
- An interactive "tty" element allows design of circuits that can interact with the user.
Support tools include a microcode/macrocode compiler to assist in creating large projects such as microprocessor designs.