UPDATE July 2017:
Who knows more about the ESQ/SQ-80 architecture than Dr. Rainer Buchty?
The answer is:
No one alive, that’s who. I imagine this includes the original hardware team AND the guys who wrote the RAD SOFTWARE!
So I would be irresponsible if I didn’t point out that he has encouraged me to update the information on this page several times. And I have failed to do so (insert that chocolate ice cream emoji here)...
In his own words, I got several hardware details wrong. For example:
There of course is a timing circuit (the DUART timer) which drives the kernel task switcher. This task switcher in turn defines an overall hardware timing, which is shared, among other things, by LFOs and envelopes. This is embedded in one of the four main tasks.
Of zero and near-instant time parameters, he writes:
Nothing prevents an envelope to go from 0 to $LEVEL in zero or close-to-zero time. You can load a capacitor arbitrarily fast to bring it up to the desired voltage… Within the max current range, of course. --But if it's fast enough for discharging to produce a sawtooth wave in the audio range, then it's fast enough for envelope generators to consider it “indistinguishable from instantaneous”.
I’m paraphrasing a little, so any inaccuracies are in my wording, not in the initial information. Thanks, Doc, for your wisdom and experience with the hardware and software.
And I think my new band name will be “Indistinguishable from Instantaneous”