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From: John_H on 26 Mar 2010 23:38
On Mar 26, 9:34 pm, Symon <symon_bre...(a)hotmail.com> wrote:
> On 3/26/2010 3:15 PM, Thomas Stanka wrote:> On 25 Mrz., 17:18, Jason Thibodeau<jason.p.thibod...(a)gmail.com>
> > Second problem, how do you avoid having more than one level
> > transaction in the oscillation ring?
> > (e.g. 01010).
>
> > bye Thomas
>
> Isn't the 01010 thing gonna resolve itself PDQ? It must be an unstable
> state.
>
> Syms.

It may be unstable in the long run but how long? Any idea how
solitons work? Me neither. Weird stuff happens. It could be that
the falling edge travels slower than a rising edge but at the same
time builds up a short time-duration effect that slows a rising edge
down below the falling edge speed. The rising edge gets close enough
to the falling edge to be slowed down to match the speed. Precisely.
Ring oscillators DO often support multiple pulses.

Gabor pointed out that "Normally a ring with a single enable input
wouldn't behave that way" (having multiple transitions) but what we
have is code created by an individual. Did he design the "normal"
ring oscillator or an abnormal one? Since there were questions,
concerns, and doubts I'm not confident the ring was designed with the
ability to exclude glitches. "Normal" comes from experience.
From: -jg on 27 Mar 2010 02:00
On Mar 27, 1:34 pm, Symon <symon_bre...(a)hotmail.com> wrote:
> On 3/26/2010 3:15 PM, Thomas Stanka wrote:> On 25 Mrz., 17:18, Jason Thibodeau<jason.p.thibod...(a)gmail.com>
> > Second problem, how do you avoid having more than one level
> > transaction in the oscillation ring?
> > (e.g. 01010).
>
> > bye Thomas
>
> Isn't the 01010 thing gonna resolve itself PDQ? It must be an unstable
> state.

Hehe.. perhaps in theory... ;)

- I went looking for this on the bench a while ago, and it is not as
'unstable' as you might think!
I managed to start, and run, ring oscillators with
shorter periods...
My conclusion was that local LCR artifacts meant the trend lines were
not monotonic... and so a reset line is always a good idea.
-jg


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