OSVVM is an advanced verification methodology that defines a VHDL verification framework, verification utility library, verification component library, scripting API, and co-simulation capability that simplifies your FPGA or ASIC verification project from start to finish. Using these libraries you can create a simple, readable, and powerful testbench that will boost productivity for either low level block tests (unit tests) or complex FPGA and ASIC tests.

OSVVM is developed by the same VHDL experts who have helped develop VHDL standards. We have used our expert VHDL skills to create advanced verification capabilities that provide:

• A structured transaction-based framework using verification components that is suitable for all verification tasks - from Unit/RTL to full chip/system level testing.
• Test cases and verification components that can be written any VHDL Engineer.
• Test cases that are readable and reviewable by the whole team including software and system engineers.
• Unmatched reuse through the entire verification process.
• Unmatched test reporting with HTML based test suite reports, test case reports, and logs that facilitate debug and test artifact collection.
• Support for continuous integration (CI/CD) with JUnit XML test suite reporting.
• Powerful and concise verification capabilities including Constrained Random, Functional Coverage, Scoreboards, FIFOs, Memory Models, error logging and reporting, and message filtering that are simple to use and work like built-in language features.
• A common scripting API to run all simulators - including GHDL, NVC, Aldec Riviera-PRO and ActiveHDL, Siemens Questa and ModelSim, Synopsys VCS, and Cadence Xcelium.
• A Co-simulation capability that supports running software (C++) in a hardware simulation environment.
• A Model Independent Transaction (MIT) library that defines a transaction API (procedures such as read, write, send, get, …) and transaction interface (a record) that simplifies writing verification components and test cases.
• A rival to the verification capabilities of SystemVerilog + UVM.

You can find an overview of OSVVM at osvvm.github.io. Alternately you can find our pdf documentation at OSVVM Documentation Repository.

You can also learn OSVVM by taking the class, Advanced VHDL Verification and Testbenches - OSVVM™ BootCamp

A great way to get oriented with OSVVM is to run the demos. For directions on running the demos, see OSVVM Scripts.

OsvvmLibraries contains all other OSVVM repositories as submodules. If you want everything, this is the one you need to clone.

Be sure to use “–recursive” to include the submodules:

  $ git clone --recursive https://github.com/osvvm/OsvvmLibraries

Get a zip file from osvvm.org Downloads Page.

The OSVVM Utility library (named osvvm) implements buzz word verification capabilities including Constrained Random, Functional Coverage, Scoreboards, FIFOs, Memory Models, error logging and reporting, and message filtering that are simple to use and work like built-in language features.

The OSVVM script library implements a common scripting API to run all simulators - including GHDL, NVC, Aldec Riviera-PRO and ActiveHDL, Siemens Questa and ModelSim, Synopsys VCS, and Cadence Xcelium.
Our motto: "One Script to RUn them ALL"

The Model Independent Transaction (MIT) library (osvvm_common) defines a transaction API (procedures such as read, write, send, get, …) and transaction interface (a record) that simplifies writing verification components and test cases. The MIT library is used (and required) by all OSVVM verification components. Usi8ng OSVVM MIT makes verification component deveopment as easy as any "Lite" based approach.

The OSVVM Verification Component Libraries are a growing set of verification components commonly used for FPGA and ASIC verification. Each family of verification components is a separate git repository. The library currently contains the following repositories:

• AXI4 Repository
  • Axi4 Full Manager (burst), Memory (burst), Subordinate Verification Components
  • Axi4 Lite Manager and Subordinate Verification Components
  • AxiStream Transmitter and Receiver Verification Components
• UART Repository
  • UART Transmitter and Receiver
• DpRam Repository
  • DpRam behavioral model
  • DpRam Manager VC to read and write to the DpRam interface
• Ethernet xMII Repository
  • Verification components for Ethernet Phy and MAC that support GMII/RGMII/MII/RMII.

OSVVM co-simulation supports running software (C++) in a hardware simulation environment.
This includes either writing tests cases in C++ or running C++ models such as instruction set simulators.

PDF documentation for all things OSVVM.

OSVVM verification components use records for the transaction interfaces, so connecting them to your testbench is simple - connect only a single signal.

The OSVVM methodology uses records whose elements are a resolved type from the package ResolutionPkg.vhd.

The long term plan is to switch to VHDL-2019 interfaces. VHDL-2019 uses records just like OSVVM and adds mode views. So the transition to VHDL-2019 interfaces is fairly simple. Due to their similarity, OSVVM interfaces are an effective prototype for VHDL-2019 interfaces.

Testbenches are in the Git repository, so you can run a simulation and see a live example of how to use the models.

The OSVVM project welcomes your participation with either issue reports or pull requests. For details on how to participate see

You can find the project Authors here and Contributors here.

OSVVM Forums and Blog: http://www.osvvm.org/
Gitter: https://gitter.im/OSVVM/Lobby
Documentation: osvvm.github.io
Documentation: PDF Documentation

Copyright (C) 2006-2022 by SynthWorks Design Inc.
Copyright (C) 2022 by OSVVM Authors

This file is part of OSVVM.

Licensed under Apache License, Version 2.0 (the "License")
You may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.