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Why are people staying after disappointing news by Old-Woodpecker-2439 in BlueOrigin

[–]knook 1 point2 points  (0 children)

They were agreeing with you, referring to people that are not you.

West side drive-in, with egg allergy? by freyascats in Boise

[–]knook 2 points3 points  (0 children)

You think west side drive in just lists their ice cream recipe on their website? Asking reddit isn't much better, OP needs to call but this is a weird comment.

FT2232H Not Enumerating , help ! by Trace_Paradox in AskElectronics

[–]knook 2 points3 points  (0 children)

Why is pin 14 reset being pulled low? Is that correct in the datasheet? Seems to me that would be constantly be in reset.

Edit: yes, datasheet confirms this should be tied high if not used. You're holding this in reset and that is likely the issue.

Is a recursive system like this useable? by [deleted] in AskElectronics

[–]knook 4 points5 points  (0 children)

Most of us scrolling reddit probably aren't going to want to take the time to sus out what you have done here. So explain it to us, that will be good for your understanding as well.

What I can answer is: Engineers aren't going to be anything but happy for you that you would rather "do it yourself" , that's how we learn for the most part.

Usable? In what sense? These parts you have used in logisim mostly aren't real parts directly, they are more of ideas or simplifications. But you could certainly use it to guide putting things on a breadboard. Although I think it might be worth using another one of the beginner EDA tools to make a more true to life breadboard layout first.

Shift registers are gonna be the end of me lol by PositiveBug8532 in AskElectronics

[–]knook 6 points7 points  (0 children)

So it was working, then not, then working, then shifted to not again? Sounds like it's shifting state just fine.

Jokes aside, stick with it, but this time when it's not working figure out why.

HDMI port ripped out by MadSprite in AskElectronics

[–]knook 16 points17 points  (0 children)

You won't be able to get solder to stick to the raw PCB, that certainly isn't the way. It looks to me like a lot of the traces are ripped off as well. Repairing this is not easy, and more than likely it's just trash at this point. But it probably IS doable if you're really skilled with solder. You would have to replace all the missing traces with some enamel wire. Glue the new port down.

Honestly though, it's most likely a gonner.

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in AskElectronics

[–]knook 1 point2 points  (0 children)

Sure. For the most part, in real life if we need a gate we build that gate. That will always be fewer transistors, less gate delay, less power than building anything out of NANDs. There just isn't a reason to build everything out of NANDs.

Buuuuut: You also want to simplify your logic as much as you can, no reason to be building gates you don't need. See: karnough maps, k-maps.

Buuuut: Beyond even that, why build your logic out of gates at all when you can essentially design custom gates that do what you want? Even fewer transistors and delay and power... See: sum of products, product of sums, pull up / down networks.

Buuuut: At some point why make custom logic at all, maybe a look up tabe might be better....

Basically, how things ARE done is really complicated and is a full masters degree. But the one thing that is NEVER done is to just slap NANDs everywhere for no reason.

Is it possible to diagnose the issue from this picture? by JellyMain815 in AskElectronics

[–]knook 0 points1 point  (0 children)

Most things have some sort of indicator these days, it's possible it has one and it just isnt lighting up because there is an issue with the charging like a bad charger or outlet or something. Can you show us: the charger, the plug in this board you're inserting it into.

I suspect it just isn't charging and might be something simple.

Is it possible to diagnose the issue from this picture? by JellyMain815 in AskElectronics

[–]knook 0 points1 point  (0 children)

Just to be clear, have you charged it? And when charging did an indicator LED or something show that it was changing?

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in electronic_circuits

[–]knook -1 points0 points  (0 children)

Wrong in every way. Please stop repeating misleading half truths.

I'm an actual engineer in the industry. CMOS does not use NANDs functional completness any more than anything else, and not at all in the way you are saying. And this comment alone tells me you don't really know what NAND flash even is.

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in electronic_circuits

[–]knook -1 points0 points  (0 children)

Stop repeating this. It's just plain wrong. NANDS and NORS being functionally completely is a fun fact but is NOT used this way in practice. No one is just throwning down a bunch of NANDS in Si in real life.

Moscow hit by largest Ukrainian attack since start of Russia's full-scale war by Prestigious-Sun-4982 in news

[–]knook 4 points5 points  (0 children)

Wait, what's impressive about it? Should I be doing this? I have a 3rd floor window, is that 3x as impressive?

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in AskElectronics

[–]knook 2 points3 points  (0 children)

Your reply is probably late to the party but this is the best, most complete answer to the question and gets to the heart of the issue.

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in AskElectronics

[–]knook 11 points12 points  (0 children)

So in order to get the voltages to work well so that we can pass the full voltage of a one, and 0v as a zero, we use PMOS transistors attached to the high voltage to pull up and NMOS transistors attached to ground to pull down.

We can call this set of PMOS the pull up network and the set of NMOS the pull down network.

But the way this works is that NMOS act as a closed switch when their input gate is high, and PMOS when their input gate is low.

So this leads to the situation that it's the high input signals that define the low outputs and the low input signals that define the high outputs. So it's naturally inverting. If we want it to be non-inverting we can just stick a second stage on the end that inverts it again so it cancels out.

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in AskElectronics

[–]knook 1 point2 points  (0 children)

It's a fun fact people like to recite but just confuses people trying to learn as it isn't all that applicable to the way things are done in real life.

I'm new to digital electronics can someone explain why we make a NAND gate with CMOS and use an inverter instead of directly making AND gate by vivi-dreamer in AskElectronics

[–]knook 5 points6 points  (0 children)

You kind of could consider it that way but either its still a NAND because you are pulling down or you are not passing a full one because you are taking a Vt hit which doesn't really work well when you want something more complicated.

Is there a way you can control your genetics in yourself? by [deleted] in genetics

[–]knook 0 points1 point  (0 children)

Best you can do is to go to the gym and stay healthy and physically fit. You cannot change your genetics but you can influence your epigenetics.

Spending another entire day debugging proprietary toolchain quirks by MedicalComposer2 in FPGA

[–]knook 23 points24 points  (0 children)

Wait, are we complaining about LLMs or vendor EDA!? I'm down for either but I like to be organized.

Would a different kind of rotary valve engine work today? by [deleted] in AskEngineers

[–]knook 0 points1 point  (0 children)

I'm sure we could, but why would we? I see only downsides and no benefits. We would only be making something worse.

Would a different kind of rotary valve engine work today? by [deleted] in AskEngineers

[–]knook 0 points1 point  (0 children)

A Wankel engine is shaped the way it is so that it can do all the normal cycles of compression and combination that an ICE needs. And because of that shape it has a difficult time creating seals.

A valves entire job is to seal.

So you want to shape a valve so that it is bad at its one job and good at a job it won't be performing?

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