Below you can find a list of Verilog/VHDL digital simulators.

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Veritak
 is a Verilog HDL Compiler/Simulator that supports the major Verilog 2001 HDL features. It provides an integrated environment, which includes a VHDL to Verilog translator, a syntax highlighting editor (called Veripad), a class hierarchy viewer, a multiple-waveform viewer capable of handling a gigabyte vcd files, source analyzer, and more -- it is available for Windows XP/2000/2003/Vista32/Vista64/Windows7 32bit/64bit.
Veritak is made available as shareware and its price is neglidgeble.

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NCSIM (Cadence)
 is a professional Verilog/VHDL Simulator that supports all HDL standards. NCSIM is provided by Cadence company and more detailed information can be obtained from local distributors (www.cadence.com).
For following OS platforms the simulator is available: Windows, Linux, Solaris

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Modelsim (Mentor Graphics)
 is a professional Verilog/VHDL Simulator that supports all HDL standards. Modelsim is now provided by Mentor Graphics company and more detailed information can be obtained from local distributors (www.mentor.com).
For following OS platforms the simulator is available: Windows, Linux, Solaris

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VCS (Synopsys)
 is a professional Verilog/VHDL Simulator that supports all HDL standards. VCS is now provided by Synopsys company and more detailed information can be obtained from local distributors (www.synopsys.com).
For following OS platforms the simulator is available: Windows, Linux, Solaris

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