Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Programming > VHDL > metastability

Reply
Thread Tools

metastability

 
 
fabbl
Guest
Posts: n/a
 
      01-16-2004
Chris,
To do this the tool would have to create timing paths, redundant to what
synthesis and PAR tools do. What you really need to do is design your code
with fan-out and delay in mind. Timing reports from PAR and synthesis
provide visibility into timing issues (most of the time) and will be more
reliable than something second guessing your design from a design entry
point of view.



"Chris" <> wrote in message
news:bu8qas$v0k$...
> Do any programs exist which can analyze VHDL code and predict any problems
> with metastability?
>
>



 
Reply With Quote
 
 
 
 
Chris
Guest
Posts: n/a
 
      01-16-2004
Do any programs exist which can analyze VHDL code and predict any problems
with metastability?


 
Reply With Quote
 
 
 
 
Marcus Harnisch
Guest
Posts: n/a
 
      01-16-2004
"Chris" <> writes:
> Do any programs exist which can analyze VHDL code and predict any problems
> with metastability?


Novas' nLint comes to mind. It checks whether registers in different
clock domains are connected back-to-back and reports a violation if it
could find any of the common synchronizer structures. You can also
tell it about your own synchronizer modules, which will then be looked
for. That's to cover the most common case.

Best regards,
Marcus

--
Marcus Harnisch | Mint Technology, a division of LSI Logic
| 200 West Street, Waltham, MA 02431
Tel: +1-781-768-0772 | http://www.lsilogic.com
 
Reply With Quote
 
VhdlCohen
Guest
Posts: n/a
 
      01-17-2004
>"Chris" <> writes:
>> Do any programs exist which can analyze VHDL code and predict any problems
>> with metastability?

>
>Novas' nLint comes to mind. It checks whether registers in different
>clock domains are connected back-to-back and reports a violation if it
>could find any of the common synchronizer structures. You can also
>tell it about your own synchronizer modules, which will then be looked
>for. That's to cover the most common case.
>


@HDL also provides a similar product.
http://www.athdl.com/pdf/Clock_Domain_Datasheet.pdf

-----------------------------------------------------------------------------
Ben Cohen Trainer, Consultant, Publisher (310) 721-4830
http://www.vhdlcohen.com/
Author of following textbooks:
* Using PSL/SUGAR for Formal and Dynamic Verification 2nd Edition, 2004 isbn
0-9705394-6-0
* Real Chip Design and Verification Using Verilog and VHDL, 2002 isbn
0-9705394-2-8
* Component Design by Example ", 2001 isbn 0-9705394-0-1
* VHDL Coding Styles and Methodologies, 2nd Edition, 1999 isbn 0-7923-8474-1
* VHDL Answers to Frequently Asked Questions, 2nd Edition, isbn 0-7923-8115
------------------------------------------------------------------------------
 
Reply With Quote
 
Marcus Harnisch
Guest
Posts: n/a
 
      01-19-2004
Marcus Harnisch <> writes:
> Novas' nLint comes to mind. It checks whether registers in different
> clock domains are connected back-to-back and reports a violation if it
> could find any of the common synchronizer structures.

^^^^^
could not

I sure you got that, but still...

--
Marcus Harnisch | Mint Technology, a division of LSI Logic
| 200 West Street, Waltham, MA 02431
Tel: +1-781-768-0772 | http://www.lsilogic.com
 
Reply With Quote
 
Jos De Laender
Guest
Posts: n/a
 
      01-19-2004
Chris wrote:

> Do any programs exist which can analyze VHDL code and predict any problems
> with metastability?


Guess you should be a bit more specific on what you mean ...

Do you really mean 'metastability' ? This being a physical phenomenon ,
there's no way to predict this on the VHDL (logical) level.

Or are you referring to - as other posters are interpreting it - predicting
trouble because I was sloppy in synchronizing ? There all major EDA vendors
have something in their portfolio to help you ...

--
Jos De Laender
 
Reply With Quote
 
fabbl
Guest
Posts: n/a
 
      01-20-2004
I'd like to add that I don't think it is a good idea to try to predict
place/route results at the logical level. Think about how a tool would have
to do this. It's best to read STA reports and design with timing in mind.
I'm sure the market may see the demand for a tool and try to fill it, I'm
skeptical as to the trustworthiness of the results.


 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Will metastability not occur at the same clock domain? Tsun VHDL 1 11-29-2011 05:09 PM
Avoiding metastability on asynchronous inputs Ardni VHDL 0 11-07-2008 12:05 PM
Metastability or what? woko VHDL 3 09-05-2005 07:52 AM



Advertisments
 



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57