Re: [sv-ac] Proposal uploaded for Mantis 2654 (Ballot Comment #93)

Hi Ed,

Yes.  However, when I look at a waveform viewer I never see the sampled 
value of a signal.  I only see the signal.  The text and diagrams will 
be much more clear if they show actual signal values.  Note that Figure 
16-3 shows actual signal values changing in the middle of the cycle as well.

I have uploaded a new proposal which makes fixes to 16-12 and 16-13.  I 
believe that both these figures are within the scope of this comment. 
Fixes for 16-14, 16-15, and 16-16 will have to wait unless there is 
another comment covering them.

Tom

On 04/24/09 11:33, Eduard Cerny wrote:
> Hi Tom,
> 
> Fig 16-14: if it shows sampled values, then I do not think the figure is wrong, it is missing the failures, but the success is correct. The figures rely on the fact that sampled values are shown.
> 
> ed
> 
> 
>> -----Original Message-----
>> From: owner-sv-ac@eda.org [mailto:owner-sv-ac@eda.org] On Behalf Of
>> Thomas Thatcher
>> Sent: Friday, April 24, 2009 2:24 PM
>> To: Lisa Piper
>> Cc: sv-ac@eda.org
>> Subject: Re: [sv-ac] Proposal uploaded for Mantis 2654 (Ballot Comment
>> #93)
>>
>> Hi Lisa,
>>
>> The other diagram don't just LOOK off.  They are wrong!
>>
>> In Fig 16-13, the same waveform changes need to be made that I made for
>> Fig 16-12.
>>
>> Fig 16-14 is just plain Wrong!  If you look at the property:
>>
>>      property data_end;
>>         @(posedge mclk)
>>         data_phase |-> ((irdy==0) && ($fell(trdy) || $fell(stop))) ;
>>      endproperty
>>
>> In the waveform given in 16-14, the property succeeds in cycle 7, not
>> in
>> cycle 6.  However, the Property Fails in cycles 3, 4, 5, 7, 8, and 9!
>> This is not shown in the figure.
>>
>> With this example, it might be better to just reverse the implication.
>> The property as written doesn't really make sense.  i.e.
>>
>>         ((irdy==0) && ($fell(trdy) || $fell(stop))) |-> data_phase
>>
>> Figures 16-15 and 16-16 are wrong as well.  In Figure 16-15 the
>> sequence
>> data_end_exp should match in cycle 7, and data_end_rule should evaluate
>> to true in cycle 9.  Figure 16-16 repeats the error from 16.14.
>>
>> However, since the comment only mentioned one figure, we probably don't
>> have authority to change all four diagrams.  I will change both 16-12
>> and 16-13, as they are part of the same example.
>>
>>
>> Our options:
>> 1.  Make the change I suggested, moving the signal transitions to the
>> middle of the cycle.
>> 2.  We could pull the signal transitions all the way to the previous
>> cycle.  If we did this, I would add the "the sampled value" to the text
>> explanation below, like this:
>>
>>         Because the sampled value of signal burst_mode is hight at
>> clock
>>         tick 1 and low at clock tick 2 . . .
>>
>> 3.  We could leave the signal transitions alone.  If we did that, we
>> would need to edit the figure anyway to move the match indications one
>> cycle later.  We would then need to edit the explanation text to change
>> the cycle numbers.
>>
>> Tom
>>
>> On 04/23/09 18:53, Lisa Piper wrote:
>>> Hi Tom,
>>>
>>>
>>>
>>> The problem I have with this solution is that it makes other diagrams
>>> look off too.  For example - Figure 16.13 and 16.14. I thought
>> someone
>>> (Ed??) was going to look at clarifying that the signals shown in the
>>> diagram are actually depicting the sampled values of signals, in
>> which
>>> case the change would be to say:
>>>
>>>
>>>
>>> "Because the sampled value of signal burst_mode is high at clock tick
>> 1
>>> and low at clock tick 2, $fell(burst_mode) is true at
>>>
>>> clock tick 2."
>>>
>>>
>>>
>>> Lisa
>>>
>>>
>>>
>>> Ps Figure 16.14 is misplaced too in my copy
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: owner-sv-ac@server.eda.org [mailto:owner-sv-ac@server.eda.org]
>> On
>>> Behalf Of Thomas Thatcher
>>> Sent: Wednesday, April 22, 2009 12:59 PM
>>> To: sv-ac@server.eda.org
>>> Subject: [sv-ac] Proposal uploaded for Mantis 2654 (Ballot Comment
>> #93)
>>>
>>>
>>> Hello Everyone,
>>>
>>>
>>>
>>> I have uploaded a proposal for Mantis 2654 (ballot comment #93).  The
>>>
>>> solution for this comment was simply to edit Figure 16-12, and move
>> the
>>> signal transitions forward to the middle of the cycle, before the
>> clock
>>> edge.  I re-created part of the figure to illustrate the change.  Let
>> me
>>> know if I need to do something more to help the editor with this
>> change.
>>>
>>>
>>> Thanks,
>>>
>>>
>>>
>>> Tom
>>>
>>>
>>>
>>> --
>>>
>>> This message has been scanned for viruses and
>>>
>>> dangerous content by MailScanner, and is
>>>
>>> believed to be clean.
>>>
>>>
>>>
>> --
>> This message has been scanned for viruses and
>> dangerous content by MailScanner, and is
>> believed to be clean.
> 
> 

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.