[ibis-macro] Re: FW: Question on clock_times

  • From: Scott McMorrow <scott@xxxxxxxxxxxxx>
  • To: Wenyi.Jin@xxxxxxx
  • Date: Fri, 26 Mar 2010 17:33:46 -0400

The specification is not clear concerning the meaning of the clock_times vector. I see two valid interpretations: 


   * Clock_times are relative to the start of the current block
   * clock_times are relative to the start of the 1st block
I do not see this defined in the specification. If it is, then please point me to the section. 

--
Scott McMorrow
Teraspeed Consulting Group LLC
121 North River Drive
Narragansett, RI 02882
(401) 284-1827 Business
(401) 284-1840 Fax

http://www.teraspeed.com

Teraspeed® is the registered service mark of
Teraspeed Consulting Group LLC



Jin, Wenyi wrote:
(1) for CASE 2 and CASE 3, how can clock_time begin from 0? It is already 2^nd block.
(2) If some call generate valid clock_time, some not, that means DLL has to track
the information like block number to decide from which block begin return clock time.
(3) DLL can always return clock time even CDR is in lock-in stage, it is the EDA tool that
Specified after how many UI or block, to make use of clock_time. *From:* ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] *On Behalf Of *Dmitriev-Zdorov, Vladimir 
*Sent:* Friday, March 26, 2010 2:08 PM
*To:* ibis-macro@xxxxxxxxxxxxx
*Subject:* [ibis-macro] Re: FW: Question on clock_times
Please clarify if the following clock time patterns are legitimate when performing several GetWave calls (for simplicity/brevity, let's assume that we have only 10 bits per call and will use integers instead of small double values). Which of the following 3 cases are allowed? 


CASE 1:


After the 1-st call:

0 1 2 3 4 5 6 7 8 9 -1


After the 2-nd call:

10 11 12 13 14 15 16 17 18 19 -1


After the 3-rd call:

20 21 22 23 24 25 26 27 28 29 -1


etc.


CASE 2:


After the 1-st call:
-1 # # # # # # # # # # // First call does not generate clocks 


After the 2-nd call:

0 1 2 3 4 5 6 7 8 9 -1


After the 3-rd call:
10 11 12 13 14 15 16 17 18 19 -1 // time increment continued from the last call 


etc.


CASE 3:


After the 1-st call:

-1 # # # # # # # # # #


After the 2-nd call:

0 1 2 3 4 5 6 7 8 9 -1


After the 3-rd call:

0 1 2 3 4 5 6 7 8 9 -1    // i.e. always start from zero


etc.


-----Original Message-----
*From:* ibis-macro-bounce@xxxxxxxxxxxxx [mailto:ibis-macro-bounce@xxxxxxxxxxxxx] *On Behalf Of *Muranyi, Arpad 
*Sent:* Friday, March 26, 2010 2:38 PM
*To:* ibis-macro@xxxxxxxxxxxxx
*Subject:* [ibis-macro] FW: Question on clock_times


Kumar,


So are you saying that the vector can begin

with a bunch of -1 and then have valid number

later in the vector?  Lie this:


-1 -1 -1 -1 # # # # # # # # -1 -1 -1 -1


If this is true, is it also true that you can

have alternating -1 and good values in the

vector?  Like this?
-1 -1 -1 -1 # # # # # # # # -1 -1 -1 -1 -1 -1 -1 -1 # # # # # # # # -1 -1 -1 -1 


Arpad

==============================================


------------------------------------------------------------------------

*From:* C. Kumar [mailto:kumarchi@xxxxxxxxx]
*Sent:* Friday, March 26, 2010 3:29 PM
*To:* Muranyi, Arpad
*Subject:* Re: [ibis-macro] Question on clock_times

arpad:
let me take shot at this

1. Yes -1 indicates end of clock vector
2. clock vector is the clocks associated with the particular wave vector in the particular getwave call. 

3. some models can have delayed start for returning a clock vector.
Once a legitimate clock vector is returned , the eda tool is expected to use that information to sample the wave returned by the getwave call. Other wise the eda tool may rely on its own devices to sample the wave, (usually this is an 'ideal' clock)
4. some models may modify the wave form but may never return a clock vector. (i.e -1 in the first position) 


------------------------------------------------------------------------

*From:* "Muranyi, Arpad" <Arpad_Muranyi@xxxxxxxxxx>
*To:* ibis-macro@xxxxxxxxxxxxx
*Sent:* Fri, March 26, 2010 4:08:16 PM
*Subject:* [ibis-macro] Question on clock_times

Hello AMI experts,

I would like to ask a question about the clock_times vector.
The spec says that "The last clock in indicated by putting a
value of -1 at the and of clocks for the current wave sample".

We got a DLL from a vendor which seems to fill the vector
for the first few GetWave calls with -1 and then it starts
filling it with good numbers.

What is the interpretation of the specification?  First,
does the above text refer to the entire vector, or each
little section independently that a single GetWave call
returns?

If it is for the entire vector, then having -1 in the first
few thousand locations would mean that everything else
after that is garbage, correct?

If it is per GetWave call, is the EDA tool expected to
assemble something from bits and pieces that are returned
by the various GetWave calls?

Thanks,

Arpad
===============================================================
---------------------------------------------------------------------
IBIS Macro website  :  http://www.eda.org/pub/ibis/macromodel_wip/
IBIS Macro reflector:  //www.freelists.org/list/ibis-macro
To unsubscribe send an email:
To: ibis-macro-request@xxxxxxxxxxxxx <mailto:ibis-macro-request@xxxxxxxxxxxxx> 
  Subject: unsubscribe



--
Scott McMorrow
Teraspeed Consulting Group LLC
121 North River Drive
Narragansett, RI 02882
(401) 284-1827 Business
(401) 284-1840 Fax

http://www.teraspeed.com

Teraspeed® is the registered service mark of
Teraspeed Consulting Group LLC

Other related posts:

  1. Home
  2. ibis-macro
  3. Archive
  4. 03-2010