Maybe I understand it a bit better now.
All parts are used many times or all the time and switching time is what makes it closer to goal.
(I have that HP Journal but it's in the que)
With noise I didn't mean ripple but more generally something that flips the error flag up.
My understanding of the value generation is seeking it using iterations and flipping comparator U7 is telling it's too far now.
That bit value is then put out to controller using ID7.
You can try trigging it with U6 pin 13 of digital board.
(right of text of down of 4 D-flops of upper left corner)
If you get much less than 20 bits you're probably getting only partial value and next part is completely its own thing and next pin 13 down/up.
It's also possible that you're getting same bit values.
The pin is operating so that first D-flop's R is up and Q is down, then R goes down allowing next S put Q permanently up, clock is never happening so D is also never happening.
With storing the trigger channel also you can see how long you should get bits.
Why High Res.
Last reference is so close to input that comparator misbehaves.
If iteration starts from center and comparator indicates less in both directions the value is exactly there in the middle.
But if comparator starts indicating more in both directions it's an error.
I don't understand those completion part offsets.
(3-73 of O&S)
Finally Q4 and Q8 are opened, Q5, Q6 and Q7 closed and offsets stored.
Where, the sample is complete and circuits are autozeroed.
The operation of the meter is pretty slow compared to what is available now.
So pretty much any logic analyzer will do.
I have many never used China gadgets.
Two months shipping brings up anybody's inner fortune teller.
Anyway, one of those is USB logic analyzer and no idea how it works, close to
https://www.sparkfun.com/products/15033A/D 383984 seems to be the only module version in all models.
Much more likely you are upsetting the software with almost anything else.