On Wed, 12 Feb 2003 steve@spiketech.com wrote:
Interesting points. I still disagree though, the fact that a timing
diagram implies by the placement of events relationships between
signals which may not exist. Timing diagrams are often ambiguous about
sets of transitions for which there is no required ordering but one
is often present in common usage. I probably have a skewed view here
as I don't generally work with clocked circuits.
Well, I almost exclusively work with clocked circuits. Perhaps that is
the largest reason for a difference of opinion.
Timing diagrams still serve a place in my design bag of tricks.
Agreed, I usual used them to expand particular examples of interfaces
but I prefer to specify interfaces in other ways.
Actually, from a GTKWave point of view, being able to annotate with
causal-relationship arrows (either by hand or from a textual/graphical
spec) would be quite cool and very handy for visualising relationships
between signals in real communications (or example communications acting
as specs.).
I see two different applications here - one of which already has some
support, the other which is more along the lines similar to the product
"Timing Designer." We can already add labels and comments to our traces
using GTKwave if memory serves. You can't draw connective arrows
between waveforms on the drawing area though (If I understand what you
are talking about). At the same time there is a definite place for a
program that can create waveforms effiiciently just for documenation
purposes. Heck - something that could be edited in a word document or at
least included as a graphic would be the use for such a tool. I suspect
you can get by with some of the vector graphic tools - but something
that was build to display waveforms in particular, allow annotation as
you mentioned, and could include values in a "pretty" manner within the
waveform would be of utility.