[sdiy] (chuckle)....did I hear somebody say...SEQUENCER!!!!!!!

[Peter Grenader]

Les Mizzell wrote:

> 
> 
> Just out of curiosity, what's the upper clock rate for this thing?

About 700 hertz and here's why:

This sequencer does not have it's own clock., it needs an external clock to
operate.  I did this because I wasn't comfortable with any internal clock
design I could manifest and didn't want to run into limitations due to that,
drift being my largest concern.

Anyone who's had some experience with counters has realized that you run
into problems with timing and truth tables due to the ON time of the various
signals going into these inputs at any given time.  A way around this
potentially serious problem is to waveshape the pulse width of the input
stimuli AFTER they are in the box, thus limiting the on time interaction of
the various signals.  I've done this by one shots, using an RC to the base
of the transistors which process all incoming pulse signals.  In short,
there is a set max on time of 15 ms of all incoming signals as as they
received by the counter.

So that's what feel comfortable quoting as the limit, because that's the
limit I've accounted for in the design.  it will in fact run faster than
that, but the attributes of the beast may change at that point, because you
are forcing the RCs to reset before they're fully charged and there are
other things coming into play at that point.

I have a test patch giving Milton a little exercise right now. as soon as
his workout is over (i'm gonna give it a couple of more hours), depending on
if it catches on fire or not (a joke...kind of), i'll run it to the rails
and stick a frequency counter on there and give you all an update.

- P

> 
> Audio rate would be really nice!
>