🚀 go-pugleaf

I am trying to construct a circuit that will provide a multistable
vibrator type signal given an impulse signal...

Let me explain why I am trying to accomplish this.  I have an old
Analog Synth (A Roland SH-101) that I am trying to sync to the rest of
my midi studio.  The 101 has an external clock input which I can use to
sync it's internal sequencer with the rest of my setup.  To build a
MIDI->Clock circuit is a much greater undertaking in both time and
expense than what I am trying to accomplish.  While rummaging through my
studio the other day, a thought occurred to me, I also own a Roland
TR-505 drum machine.  Although this machine doesn't have any sync
outputs or anything, it does have a little led on it that blinks on (i
believe) every other quarter note (half notes). Ideally, what I would
like to do is use this led to create a clock signal, but expand the
signal so that it is a multivibrator during the time it isn't on.  With
four years of Computer Engineering under my belt, my brain tells me that
this is not possible without some sophisticated software with out any
slew...the reason I say this is this is how the signal looks:

      |--------|    	                |
      |        |                        |
      | <-t1-> |      <-  t2  ->        |  etc...
      |        |                        |
      |        |                        |
-------        -------------------------|

Where t1 is always the same value regardless of tempo but where t2
varies according to tempo.  In other words, unless I use this straight
signal and invert it and feed the 101 with that there is no way I can
get a reliable clock signal to the 101.  

	The other thing I was thinking about was if I could either find
where the led circuitry was I might be able to increase the rate at
which it blinked or even more simply directly feed the clock signal from
the chip (The clock signal for the tempo generation not the clock signal
Of the circuit), I could reduce the frequency of it to a usable form.
From what I saw of the 505 inside, it looks like a lot of pre-fab
micro-controllers which would be what one would most likely expect in a
product which was mass produced.  Anybody have any tips in dealing with
these types of beasts.  I presume that although the majority of the
hardware is probably the DAC and memory (it is one of the first sampled
drum machines) there is probably a section dedicated to tempo
generation.  BTW It is quite possible for me to slave my studio to the
clock of the drum machine, so this is another reason, why it would be
beneficial to find the clock generator.

Any comments or suggestions welcome

Regards,
EM