Re: [myhdl-list] Developing PLI module for cosimulation with VCS

[James L. <rob...@gm...>]

Hi all,

Thanks for the quick responses. I'm hoping this gets placed into the same
email chain, since I foolishly forgot to subscribe to the mailing list
before sending my previous post.

I tried compiling both the icarus and cver versions of the PLI modules and
linking them in as shared objects, but the simulation seems to hang. I can
confirm the callbacks are being executed by placing some debug print
statements in myhdl_vpi.c, but when I dump the VCD, no signals are
generated, so I'm convinced the VPI routines are not communicating signals
correctly between the Python and the RTL.

Previous to attempting to use VCS, I used iverilog for cosimulation
successfully. So I am using all the same code with the only modifications
being how the simulator is called on the Python side to create the
Cosimulation object.

I am using the 0.7 release right now, but I will go ahead and try with the
latest dev release and report back with findings.

Best,
James

On Thu, May 10, 2012 at 10:23 PM, James Lee <rob...@gm...>wrote:

> Hi,
>
> I'm hoping to hack the PLI module for cosimulation with iverilog to make
> it compatible with VCS.
> Has anyone attempted something like this already and possibly provide me
> with some insight on what changes would need to be made?
>
> Just based on what I read about the iverilog implementation, it seems like
> the biggest hurdle is figuring out what type of callback to use and when.
> Would looking into if VCS can use the cbReadWriteSync callback instead of
> the cbReadOnlySync be a good place to start?
>
> Thanks,
> James
>