200e

hm... i think i said that backwards in the old post. it was true for
whatever i was actually looking at, which may have been an original
281,  or maybe some weird flavor of 249e.

BUT the 200e spec says that pulses are triggered on the rising edge of
the 10v transient pulse. (lo -> hi transition); that said, i'm not
totally sure that this is how pulse detection is implemented on all
modules. it's unlikely we would notice if it was backwards because the
10v transients are so very very short.

if you are actually using a pulse generator where the 10v segments are
long enough that it makes a difference, then you should be able to
discern the 2__e-s behavior from that setup.
if you can't discern the behavior, it's probably a moot point.
if you can, and it's negative-edge triggered, that's technically a
bug, and could be fixed pretty easily (in firmware).

i don't really know what serge pulses look like... if they don't go at
least above 8v, they will not be recognized as pulses by 200e modules.

-eb


On Thu, May 29, 2008 at 1:53 PM, jjsynth <jjsynth@yahoo.com> wrote:
> falling edge: that i extrapolated from a post by ezra buchla (msg
> #618) where he explains about pulses used for clocking a sequencer. he
> wrote: ... you could also use an analog pulse as a clock any voltage
> with a
> (>=10v) -> (<10v) transition will work as long as the voltage source
> and the 200e share a ground. ... which I interpreted as triggering on
> the falling edge of the pulse. But maybe I'm completely wrong, that's
> why I asked.
>
> regards,
>
> J
>
> --- In 200e@yahoogroups.com, "Mark Verbos" <verbos2002@...> wrote:
>>
>> Who said Buchlas trigger on the falling edge of a trigger? A 281 has a
>> switch to select between AD and AR responses. What's happening when
>> that switch is thrown is that the level is being shifted so that the
>> input comparator is responding to either the 10 volt spike at the
>> beginning or the 5 volt gate (with duration). The length of the spike
>> at the beginning of a Buchla pulse is very short, but that really has
>> no bearing on the speed of the triggering. I would worry more about
>> the Serge sending out 5 volt gates. With those, you should be unable
>> to use the AR mode on the 281.
>>
>>
>> Mark
>>
>>
>>
>>
>>
>> --- In 200e@yahoogroups.com, "jjsynth" <jjsynth@> wrote:
>> >
>> > hello,
>> >
>> > after reading most of the posts in the archive I've come to understand
>> > that the falling edge of a pulse with a max level > 10V serves as a
>> > trigger (leading me to believe that this trigger pulse must have a
>> > very short duration). Has anyone in the group successfully triggered a
>> > 281e from a Serge? I have read that someone uses a TKB with his
>> > Buchla, but I am not sure how you would get a trigger to the Buchla
>> > that is in sync with other envelopes in the Serge when these are
>> > triggered on the rising edge whereas the Buchla triggers in the
>> > falling edge...
>> >
>> > thank you for your help,
>> >
>> > J
>> >
>>
>
>