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Xeys42 wrote: ↑Mon Dec 02, 2024 8:54 pm Still doesn't add up. The way I see it is this:

Looking at the 3 pictures on my first post above:

'And' works as expected as input 1 is on and input 2 is off.
'Nor' and 'Xnor' don't work as expected as 1 is on, 2 is off and according to truth tables in this state the output should be off.

When input 1 is connected to the Mini LFO, it is alternating between (0V / 'Off' / Logic Low) and (+5V / 'On' / Logic High) on a regular basis, as shown by the red Multi-Oscilloscope trace in my most recent post.

utdgrant wrote: ↑Mon Dec 02, 2024 9:59 pm When input 1 is connected to the Mini LFO, it is alternating between (0V / 'Off' / Logic Low) and (+5V / 'On' / Logic High) on a regular basis, as shown by the red Multi-Oscilloscope trace in my most recent post.

Exactly, that's more or less what I said about the LFO inverting the signal and not the gates as stated in a post by ColinP.

Logical inversion (NOT) is an operation that takes an input and produces an output.

Its truth table is...

A Q
0 1
1 0

So when its input (A) is 0 its ouput (Q) is 1 and when its input is 1 its output is 0.

The Mini LFO isn't doing any inversion, instead its square wave output produce a signal that alternates between 0 V and 5 V (which the logic gates interpret as 0/1, false/true, off/on).

Lets look at the truth table for NOR again...

A B Q
0 0 1
0 1 0
1 0 0
1 1 0

Now in the patches in question the B input is always 0 so we can simplify the truth table and omit the rows where B is 1...

A B Q
0 0 1
1 0 0

We can further simplify the truth table as the B column has no impact on the result. So we end up with...

A Q
0 1
1 0

This is exactly the same truth table as inversion so a 0 input produces a 1 output and a 1 input produces a 0 output.

So in conclusion, a NOR gate with one input that is always 0 acts as a NOT gate (commonly called an inverter) that inverts the signal from the Mini LFO.

Xeys42 wrote: ↑Tue Dec 03, 2024 11:03 am

utdgrant wrote: ↑Mon Dec 02, 2024 9:59 pm When input 1 is connected to the Mini LFO, it is alternating between (0V / 'Off' / Logic Low) and (+5V / 'On' / Logic High) on a regular basis, as shown by the red Multi-Oscilloscope trace in my most recent post.

Exactly, that's more or less what I said about the LFO inverting the signal and not the gates as stated in a post by ColinP.

I think this is a problem of definitions.

"Invertion" is a process with an input and an output. The output is a function of the input.

The Mini LFO is not inverting ANY input signal, because it does not have a signal input jack.
The Mini LFO is outputting a square wave signal which OSCILLATES between the values of 0V and +5V. The clue is in the name "Low Frequency OSCILLATOR".
The Mini LFO is a signal SOURCE.

The NOR and XNOR gates in your patch (and my patch) are INVERTING the signal presented to their left-hand input jack. They then send the INVERTED input signal to the gate's output jack.
The OR and XOR gates in my patch are buffering / replicating the signal presented to their left-hand input jack. They then send the NON-INVERTED input signal to the gate's output jack.
The logic gate is a signal PROCESSOR.

You can use the ACE Comparator (available free of charge in the Dome Music Tech Freebie Collection) as a single-input logic NOT gate / inverter:
The red trace is the raw oscillating Mini LFO output signal. The green trace is the Mini LFO output signal after it has been processed (logically INVERTED) by the ACE Compare module.

Thanks guys, my brain hurts now, lol. I will study the replies and come back here once I've fully understood everything. In the meantime I will also check out the Dome Music Technologies package.

After further studying this thread, I believe I've been misunderstood.

Let's read again what I wrote in an earlier post:

"Looking at the 3 pictures on my first post above:
'And' works as expected as input 1 is on and input 2 is off.
'Nor' and 'Xnor' don't work as expected as 1 is on, 2 is off and according to truth tables in this state the output should be off.
I went on the test the Boolean module by having nothing plugged into the inputs and only the output plugged into the sequencer. Obviously this means both inputs are off. All the 6 different boolean modes worked as expected in this case.
This backs up my original theory that the LFO pulse wave signal must be inverting the output, not the module itself as suggested in one of the replies above."

Ok, I can see how this was confusing although on the right track when I wrote of how the LFO pulse wave must be inverting the output.

Let's look at this line which was part of a reply to one of my replies:

"The Mini LFO is not inverting ANY input signal, because it does not have a signal input jack."

The mini LFO clearly doesn't have an input jack. I didn't say anything about the LFO inverting an input signal.

And:

"The Mini LFO is outputting a square wave signal which OSCILLATES between the values of 0V and +5V. The clue is in the name "Low Frequency OSCILLATOR"."

That's more or less what I meant, furthermore I know what an LFO is, I know it's an OSCILLATOR and it really doesn't need to be shouted in capitals!

When I wrote "Exactly, that's more or less what I said about the LFO inverting the signal..." I didn't mean the LFO was inverting any input, I meant the LFO was inverting the signal it was sending to the Boolean operator. That was my original reasoning as to why the boolean operator wasn't behaving as expected. Now I know it's the square wave signal causing there to be an 'on/off' output as it goes up and down. from 0 to 5 volts and back again.

I was right! OK, I didn't word it correctly initially I admit, this has led to the misunderstanding I guess however, I re-explained it in my other reply which began: "Looking at the 3 pictures on my first post above:"

I now know it's the square wave changing the output of the boolean operators originally in question. What you have been trying to tell me here is what I already knew was happening at the time of writing the post quoted above.

Apologies if this comes across as a little harsh, I don't mean to be, however, above all, I totally understand what is going on now. Thanks again for your help even though this has been a most frustrating topic.

It's all a question of semantics, I suppose. Is this Mini LFO performing an analogue inversion of its triangle wave output, or is the attenuverter? Or both? Is the Mini LFO performing a logical inversion of its triangle wave output, or is the ACE Compare, with a threshold value of 0V? Or both?
It's great that all the modules in your original patch were doing "exactly what it says on the tin" and that none were in error, despite the title of the thread.

I hope you can also see how completely bonkers the original patch loooked to us, now that you understand what the individual elements are doing and how they interact with one another. I mean, even if the Boolean Logic module had been taken out of the equation, running a Mini LFO output into the Start jack of the Sequencer just seems a bit....unorthodox. Wouldn't you agree?

After further studying this thread, I believe I've been misunderstood.

Well, in my defence at least (I can't speak for anyone else), your original patch gave the impression of someone who didn't really have a firm concept of what they were trying to achieve or how to achieve it. Your subsequent replies seemed to bolster that impression and I admit to becoming increasingly frustrated with trying to find different ways to say the same thing again and again - that the CA Boolean Logic module behaves exactly as it should.

There have been other threads where newbies to the world of modular dig their heels in that they're right, and seem impervious to the explanations of other forum members. After a while, it becomes difficult to avoid getting a little snarky in return. I hope you can forgive me for lumping you in with that category of poster. And forgive me FOR SHOUTING IN ASCII.

Xeys42, Grant doesn't need me to vouch for him, but he is perhaps the kindest soul on this forum. As well as being an expert, he is extremely generous with his time, publishes more free modules than anyone else here, open-sources much of his code, always tries to help people and is a fairly skilled diplomat.

So if he's getting frustrated with you that says something!

To be honest from what you have posted I'm still not 100% sure that you now accept that 1) the Boolean Logic module functions as it should 2) that oscillators don't invert signals and 3) that a NOR or XNOR gate with one input at 0 does invert a signal.

Please don't take this the wrong way. Your contributions are welcome and we are a friendly bunch of nerds who enjoy a bit of intellectual friction.

No worries, this entire thread has certainly given my brain a good workout! Yes I've downloaded some of those free modules, have yet to fully explore them though. (Thanks UTDGrant!).

ColinP wrote: ↑Sat Dec 07, 2024 11:46 am To be honest from what you have posted I'm still not 100% sure that you now accept that 1) the Boolean Logic module functions as it should 2) that oscillators don't invert signals and 3) that a NOR or XNOR gate with one input at 0 does invert a signal.

As you will know there are a multitude of explanations, diagrams, images and infographics which explain boolean logic online, they are very easy to understand, I was referring to one or two throughout my experiments. I intend to reach a stage where I don't need to refer to them.
As for oscillators not inverting signals, in the case of the lfo I used perhaps saying 'inversion' was wrong when in fact it's cycling through on and off. However, I guess this could be seen as an inversion in a way depending on the state of the cycles.

utdgrant wrote: ↑Fri Dec 06, 2024 11:07 pm It's all a question of semantics, I suppose.

Indeed! Also I'll study the image you posted and work it out later.

utdgrant wrote: ↑Fri Dec 06, 2024 11:07 pm I hope you can also see how completely bonkers the original patch looked to us, now that you understand what the individual elements are doing and how they interact with one another. I mean, even if the Boolean Logic module had been taken out of the equation, running a Mini LFO output into the Start jack of the Sequencer just seems a bit....unorthodox. Wouldn't you agree?

No, lol. Surely when testing and experimenting anything goes?

utdgrant wrote: ↑Fri Dec 06, 2024 11:07 pm I hope you can forgive me for lumping you in with that category of poster. And forgive me FOR SHOUTING IN ASCII.

Yes.

Rest assured, if I perform any more bizarre experiments that I need help with I'll know who to ask. I think that's enough intellectual friction for now though.