Jim Lewis

Hi Jon,
Thanks for sticking with this one. Knowing which version of Questa you had made told me I needed to search harder in VendorScripts_Questa.tcl. I found the issue. It is fixed on Dev.

If you do not want to update to the Dev branch, you can edit the line in VendorScripts_Questa.tcl that says:
set SimulateOptions [concat $::VsimArgs…[Read more]

Which version of Questa are you using?

Historically Questa offered either a vsim or a vopt/vsim flow. Up until 2025, OSVVM only supported the vsim flow, but supports both vsim and vopt/vsim flow.

The startup VendorScripts_Siemens.tcl supports the vsim flow. VendorScripts_Questa.tcl supports the vopt/vsim flow.

To choose which one you…[Read more]

If you make this call:
SetSecondSimulationTopLevel glbl

Then OSVVM would do:
vsim -c -t ps -lib common_tb TbStream_SendGetBurst1_opt glbl -suppress 8683 -suppress 8684

That said, since a library is not specified for glbl, Questa will assume it to be in common_tb. So as a result, Questa may add the common_tb.glbl in their interpretation of…[Read more]

Hi Senthil,
This is now fixed on the dev branch of OsvvmLibraries on GitHub. You can get the dev branch by doing:

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

Best Regards,
Jim

It is Simon doing the heavy lifting.

Hi Eamon,
Simon posted the blog post that hopefully answers your question. See: https://osvvm.org/archives/2830

Best Regards,
Jim

Hi Eamon,
Simon posted the blog post that hopefully answers your question. See: https://osvvm.org/archives/2830

Best Regards,
Jim

Hi Eamon,
I have asked Simon to post a response to this. Unfortunately the website is having some issues with Simon being able to post a response to it. Hopefully it will be resolved shortly.

Many apologies. We usually get these type of things answered within a day or two of the post.

Best Regards,
Jim

Hi Senthil,
I will have this fixed shortly on the dev branch.

Best Regards,
Jim

Hi Senthil
OutputHomeDirectory is not the correct variable to be setting.
Please use OutputBaseDirectory.

I have tested it with settings as follows. In both of these the results are in the $CurrentSimulationDirectory.
variable OutputBaseDirectory “”
variable OutputBaseDirectory “osvvm”

I have not tested it with other than these…[Read more]

Hi Jon,
I recommend getting all of OsvvmLibraries. Then from the Script_user_guide.pdf, to start XSIM, do the following:

1.3.9 Xilinx XSIM
Using OSVVM in Xilinx XSIM is under development. So far, Xilinx seems to be able to
compile OSVVM utility library, however, we have not had any of our internal test cases
pass.
To run OSVVM scripts in XSIM,…

[Read more]

Hi Senthil,
Settings have been changed through time. What I say here pertains to the current release, 2025.06a. Typically I try to keep changes backward compatible.

You will find how to for OSVVM’s tcl and vhdl settings documented in OsvvmSettings_user_guide.pdf in OsvvmLibraries/Documentation. With respect to finding the settings files, it…[Read more]

Hi Senthil,
The next thing to know is that every feature in OSVVM VC is tested. That is why our test suite has so many test cases. Test cases for AxiStream are in the directory, OsvvmLibraries/AXI4/AxiStream/TestCases. A search for UU finds that test cases that test this capability:

TbStream_ByteHandling1.vhd – tests using X”UU” and X”WW” in…[Read more]

Hi Senthil
See OsvvmLibraries/Documentation/AxiStream_user_guide.pdf:

7.3 Setting and Checking TKeep and TStrb
On the AxiStream interface, a TStrb value that corresponds to a data value of ‘1’ indicates the value
contains valid data. A value of ‘0’ indicates it is a filler value. A TKeep value of ‘1’ indicates the value is
either valid data or a…[Read more]

Hi Minteng,
When an ID has a value of -2**31 (-2147483648), it has not been initialized yet.
OSVVM VC, such as AxiStream, initialize the TransRec.BurstFifo signal at time 0 ns delta cycle 1,
so it is not valid until time 0 ns delta cycle 2.

Are you working with an OSVVM VC or one of your own? If it is an OSVVM VC, time is either 0 ns
or the…[Read more]

Hi Remy,
Can you share exactly what you updated? Is it a particular OSVVM testbench or one of your own.

The test cases that do bursts as words will not work as they likely have dependencies on a specific size interface. The test cases that do bursts as bytes are expected to work though.

Best Regards,
Jim

Hi Hassan,
What version of OSVVM are you using? The current version is 2025.06a.
What simulator and version are you using?

> 1. When only the testbench code was compiled. Why did it say “failed”?
Perhaps you can share the log files with me so I can look at it. Ultimately I need a reproducer test case of this.
Also try puts $::…[Read more]

Hi Nigel,
In the OSVVM 2024.09 and 2025.02 releases, the 2019 compile switch was turned on if the Questa release is greater than 2024.2. With the OSVVM 2025.04a release and beyond the 2019 switch it is turned back off again. So I recommend getting the newest release of OSVVM (2025.06a) and this problem is resolved.

In Questa, your issue is…[Read more]

Hi Nigel,
In the OSVVM 2024.09 and 2025.02 releases, the 2019 compile switch was turned on if the Questa release is greater than 2024.2. With the OSVVM 2025.04a release and beyond the 2019 switch it is turned back off again. So I recommend getting the newest release of OSVVM (2025.06a) and this problem is resolved.

In Questa, your issue is…[Read more]