Questa Base


Siemens latest entry into the Questa Simulation family provides all of the benefits of their flagship simulator at the most affordable price yet. Questa Base is a high-end simulator with unprecedented verification capabilities, specifically tailored for our ModelSim user community.

Introducing Questa Base

Questa Base is the next-generation simulator for ModelSim users. It is built on the customer-proven QuestaSim engine and innovations, and comes with a host of new features and functionality from the Questa Simulator family.

Questa Base is a high-end simulator with nearly all of the Questa Core features but with a simulation speed similar to ModelSim. As with other QuestaSim products, Visualizer is now included for free.

Why move from ModelSim to Questa Base?

Siemens EDA has introduced Questa Base, a new Questa simulation configuration specifically tailored to our ModelSim user community. Questa Base contains all the current performance and features you are familiar with in ModelSim, plus enhanced features and flows including:

1. Push-button compile & data management

Less scripting, less switches to remember, less design files management, less mistakes

Questa Base supports the new Qrun flow to improve compilation turnaround and simplify simulation runs. Qrun is a single flow “wrapper” that automatically invokes the appropriate VHDL, SystemC, or SystemVerilog compiler and optimizer based on the command line arguments. Qrun distributes the source files to the appropriate compilers and the switches to the appropriate tools, there’s no need to know which tool a specific switch or source file goes to, Qrun handles that for you.

2. Built-in optimizations on your design

Optimizations automatically performed on all designs, maximising performance

Questa Base is built on the customer-proven QuestaSim engine, which uses aggressive global compile and optimization algorithms to achieve industry-leading performance. For Questa Base this means fast debug simulation, a smaller database, and full debug visibility.

3. Next-generation debugger

Including premium debug solution with every Questa Simulator

As with other QuestaSim products, Visualizer is now included for free. Visualizer provides a full debugging experience and allows you to root-cause bugs faster, with an improved waveform window, and new features like: driver/receiver tracing, advanced searching, Finite State Machine debug & cross probing, schematics with smart hierarchical flattening, schematic exploration, biometric search, and more.

4. Many More New features and commands….

Checkpoint and Restore, 64-bit Windows and Linux support, mixed language as standard, Questa Clipboard, Questa Xprop, Visualizer Causality Tracing, improved GUI, improved customisability and Quality of Life features.

Key Features and Benefits

  • Simulation in advanced optimization mode, using vopt and the QIS flow
  • Superior debug with Visualizer – Visualizer is Siemens premium debug solution, offering you full debugging capabilities. Now included with Questa Base it gives you access to an array of new debugging capabilities
  • 64-bit support for Linux and Windows
  • ‘Classic GUI’ from ModelSim still available by default. You can use the same script, same database, same commands
  • Full off-line debugging enabling you to free up simulation licenses for more simulation runs per day
  • For ModelSim users access to a host of new QuestaSim features which allows you to find bugs earlier, improve quality, debug faster, and save time and effort
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Simulation and Debug

Combines high performance and capacity simulation with unified advanced debug and functional coverage for the most complete native support of Verilog, SystemVerilog, VHDL, …

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Verification IP

Questa Verification IP (QVIP) improves quality and reduces schedule times by building protocol and methodology reusable components that support many industry standard interfaces.

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HDL Simulation

ModelSim’s award winning Single Kernel Simulator (SKS) technology enables transparent mixing of VHDL and Verilog in one design.

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