Re: [myhdl-list] Introduction and Question

[Christopher F. <chr...@gm...>]

On 12/17/12 5:48 PM, Daryl Wasden wrote:
> Hello everybody,
>
> I thought I would introduce myself, since I've been monitoring this mailing
> list for a few months and dabbling with MyHDL for about the same amount
> of time. I have had some success, and I am probably looking at making it
> my primary language for IP development.
>
> My name is Daryl, and I am a graduate student at the University of Utah. A
> big focus of my research is in implementing real-time DSP algorithms for
> applications in wireless communications. To this end, I occasionally find
> myself requiring IP blocks that are not readily available to me, and I end
> up writing my own. I have had some success, but I'm still learning. I am
> extremely interested in MyHDL because of its ability for unit testing and
> incorporating Python-based algorithm code into my test benches.
> Currently, I use VHDL most heavily, although I learned HDL with Verilog.

Thanks for the introduction and welcome!

>
> For various reasons, I would prefer the end product to be in VHDL. For
> this reason, I was wondering if any progress had been made regarding
> CoSimulation with GHDL? If not, is there any reason I shouldn't try to
> work on this myself (i.e., someone already knows that it won't work)?
>

It might be worth investigating if GHDL has updated the VPI/VHPI 
interface in the latest version of GHDL.  I monitor the GHDL 
mailing-list briefly and have not seen any updates.  I think the GHDL 
developers have mainly focused on a move to mcode.  If the status of the 
VPI/VHPI has not changed it will be some work to implement cosimulation 
with GHDL.  It will require the missing VPI functions implemented in GHDL.

> I found this link: http://www.myhdl.org/doku.php/dev:vhdl_cosim
>
> Which I think suggests that the VPI interface is supported although I'm not
> clear that it says that...

I created this page and it was intended to be a working page towards 
GHDL co-simulation support.  The page lists which VPI functions are 
supported in GHDL (as of 03-Feb-2010).  The VPI function list was not 
complete enough to attempt a VPI port for GHDL.  I do not know if things 
have changed.

> I've never used cosimulation in VHDL or Verilog
> before, so I don't know much about it (yet). The manual for MyHDL 0.7
> says that GHDL support is not there, unless I'm misreading it. Although,
> it lists GHDL in the list of possible simulators.
>

GHDL is not available for cosimulation.  But it is supported simulator. 
  The flow for using GHDL is to convert the testbenches and run a full 
VHDL simulation that can be coordinated from Python.  See the following 
for some more information.

http://www.myhdl.org/doc/current/whatsnew/0.6.html#conversion-of-test-benches

Regards,
Chris