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Today I am going to share with you some of the lesser known logic gates and components. These can still be practical, they are just often uncommon. Let's start with the implication gate, a.k.a. the IMPLIES gate.



So, basically the function of this gate is A > B = F as you can see in the screenshot below.


What this means is that if input A is high and B is low, the gate will return false. In other words, the output will be low. Any other combination of inputs will cause the output to be high, or return true.

You can invert the output and this will become an non-implication gate, I suppose you could call it a NIMPLIES gate. Or you can flip the entire design and create a converse implication gate (CIMPLIES gate?) where the inputs will be reversed so A < B = F. You could then invert that output and have a converse non-implication gate. No, I am not making this stuff up, and no, I'm not even going to try to abbreviate it.


I'm sure you've heard the term edge-triggered before, most likely referring to a flip flop. Well, this can detect a rising edge OR a falling edge. Basically it sends a short pulse whenever the input is changed from any solid state, be it high or low.

Next up will probably be the most useful as far as practicality goes.


This is a repeater that will repeat a current either direction with a 2-tick delay. Here are some shots to show it working.




This is probably the next most practical component in this thread. It allows outputs to receive and lose power in the same order. This is perfect for various piston-based builds, like anything involving a double extender.





Well I think that's good enough for this thread. I know that most of these components aren't actually based on logic. I also know all of this can be found on the Wiki. My goal was mainly to translate and break down all the technical jargon used on such a site. Most elementary redstone builders have probably seen these before, and didn't have a clue what they done, since on the Wiki it is explained using formulas, truth tables, and technical terms.

If there are any other advanced redstone components you would like me to explain, in the plainest english I can, please let me know in a reply. Or if you would just like to see more random advanced circuits explained, post that as well.

Hopefully this helps some people out.

Quote from jesus1234578

hello what are redstone logic gates

The same thing as real-life logic gates, only built with redstone.

AND gates only output when both inputs are on
OR gates will output when either input is on
XOR gates will only output when the inputs are opposite of eachother
NOT gates are simply inverters, they output when the input is off

There are many more, but these are the most basic gates.

Nice Nose_Job_For_a_Cowboy, heres a different two-way repeater, its the one I usually use.

For the ABBA Switch if anybody wants to know with the pic posted from Nose_Job_For_a_Cowboy
When the input is powered in this case the bottom piston will extend after 1 tick, the top one will extend after 5 ticks. When the input receives no power the top piston will retract after 5 ticks and the bottom one will retract after 9 ticks. ( I think LOL)

edit: Hmm while Im here Nose, I had a prob with delaying pistons (its all working now but I thought I'd ask if there was a better way I couldve gone)
The scenario, I wanted a button to extend a row of pistons on bottom then after so many ticks start my clock up to a top row of pistons. But I needed the bottom to stay extended way longer than after the top retracted, basically I added 2x repeaters into the ABBA repeater/repeater block, but on the ones powering A I added like 5 repeaters on max delay(not on the initial input). Just wondering if there wouldve been a better way to go about it or not.

Quote from THExREALxTACO

Can you show (pics, vids, or a good description) of where, why and how these could be imemented?

Except the ABBA switch, that's pretty self-explanatory.

That, and the two-way repeater is pretty self explanatory.

The IMPLIES gate is not used often, but here's a good example of it being used in a half adder:

See how both inputs are double inverted vertically? Then, on the top layer only input A is inverted. This is the IMPLIES gate that forms the carry out line, which could then carry into a full adder.

A zero-cross detector isn't used that much either, as I said, these circuits are uncommon. That's why I call them the "black sheep" of circuitry. You could use it to turn a lever into a button though, or to make a button send two pulses with exactly one second of delay between pulses. It can also be used for error detection in a machine, or as a block updater.

Quote from jesus1234578

ok i don't now what logic gates are iam only 14 dude

That doesn't make a difference. I'm 21 and there's a 15 year old kid on RDF that makes me feel like a retard. I've explained how logic gates work, do a YouTube or Google search if you want to know how to build them. I'm not going to post any pictures showing how to build basic gates. This thread is just to explain advanced and obscure circuits.

Quote from jesus1234578

i dont want to know how they work i want to know what they are

Quote from horacelam

i want to know what they are

Quote from Nose_Job_For_a_Cowboy

I've explained how logic gates work, do a YouTube or Google search if you want to know how to build them. I'm not going to post any pictures showing how to build basic gates. This thread is just to explain advanced and obscure circuits.

They're just "circuits" that process data. Just do a Google search... again.

Quote from Sku11King77

They are very basicly different ways of manipulating redstone, sometimes as simple as making two levers control one piston, or sometimes so complicated people make entire computers out of them. They work like binary coding, 0= redstone off 1=redstone on. input is what goes in (e.g turn off and on) output is what you get out (e.g two pistons move).

It's not hard to understand, I'm only 14 aswell (although to be fair I've already started A level so..) If you still don't get it just don't ask.

Pretty much this, though it's a very rough definition.

A logic gate simply performs logical functions. It takes two binary values and outputs a single value, 1 or 0. There is one exclusion to this rule, the NOT gate which is only an inverter. You can combine these to perform complex operations.

For example, in the ALU of my computer there is one half adder, and seven full adders for the addition instruction. My full adders are made with 4 logic gates put together. Input A goes into an XOR gate as well as an AND gate. Input B goes into the same XOR gate and the same AND gate, and here's where it gets tricky. The output of the XOR gate goes into input A of another XOR gate, it also goes into input B of a second AND gate. Another input of the full adder comes into play, called carry in. (or C in) This line goes to input A of the second AND gate and into input B of the second XOR gate, the output of this XOR gate is called the sum. The outputs of both AND gates go into an OR gate, the output of the OR gate is your carry out. (or C out)

Quote from wkrepelin

Being 14 doesn't keep you from understanding them. It's fine that you don't know what they are, I didn't when I was your age, but being 14 is a pretty weak excuse. Having not studied them is much better. That being said, I'm confident you have every ability to understand them should you choose to do so and would probably find it rewarding in a number of ways. I hope you consider it.

OP: Thank you very much, I am learning redstone now and already know some algebraic logic so this is perfect for me! I think others will get great use of it as well. You seem to have already sparked the curiosity of one youth. Thanks so much and keep up the good work!

I agree, like I mentioned earlier, I know a kid that's 15 and he makes me feel like the dumbest person in the world when he tries to explain things like redstone theory.

Thanks, man! That really does help to keep me motivated, it's good that you have a head start too. I completely ****ed off in school, so everything I learned about logic was self-taught. Not the best way to learn about stuff like this, took forever to find a good book that actually explained these things in a way I could understand. Stay in school, kids!

Quote from Crininson

Great guide for (roughly) intermediate level redstoners here! The only thing here that I've actually used is the ABBA switch for a friend who wanted a detector rail powered secret minecart entrance to his base. For me, it's one of the more fun ones to put together.

Now I had a question, is there an official name for a ABBAB switch or is it just that?

It's just that, the name is self explanatory as to what the circuit does. It means the signal goes high from output A to output B, and goes low from B to A.

Quote from JSPRINGY

Great post nose_job. As an intermediate redstoner, I very much appreciate this and would love to see more.

Thanks! Would it be safe to get into more advanced circuits? I would love to do topics about adders, multiplexers, shift registers and things like that, but I'm not sure many MCXBLA players are at a level where they would be interested in these things. They all would be broken down and explained, of course, just like all components in this thread.

Quote from Crininson

Oh, I know what it does, I was just curious if it had an official name or not. I've made an ABBAB switch, but can't think of anything to use it for(Beyond maybe a bridge under lava or something), so it just sits there being used as a "Hey guys, look at what I made" piece.

Even if many MCXBLA players aren't at the level for adders and the like, you may help someone break into that level by doing one of these guides.

I was just explaining why that was the name, a fun fact if you will. I suppose you could could use it for a line of torches, hook a bunch together and invert the outputs. Make it look like a light is going back and forth across the line. So far I have found no real use for an ABBA switch in a computer or anything like that.

And that's true... I hadn't thought about it that way.

Quote from JSPRINGY

Well, compared to you, I'm an amateur, however to most of the people I meet on Live, I'm the expert. So for those people like me that like to disseminate knowledge amongst our friends, these things can add to all of our overall growth as Minecrafters on Xbox Live. As far as what i think you should put up next? I think your explanations are great, but what about hooking them up to machines to show an actual purpose? You can start right where you did today and just get into progressively more advanced circuits, and I think the mechinisms they power will help people to understand them.

I know how you feel, even I am an amateur compared to a lot of redstone engineers. I seem to excel amongst Xbox players, but I think that's just because most Minecraft geniuses are "too cool" to play the XBLA version. That, and we have horrendous redstone bugs. I've actually used a couple of these and many other components, that I didn't discuss here, in my redstone computer.

http://www.minecraft...r-built-on-360/

You can find me explaining nearly every aspect throughout the thread. I found it difficult to explain though, even after explaining what ever part of the machine does, most people didn't see the actual point of it. It's one of those things you have to be able to see as a whole. And the truth is there really isn't a point when you think about it. In Minecraft, you're building stuff yourself, so no redstone game or GPU or whatever is in a certain "format" and you don't need a computer. If you build these things, by themselves, they will run a lot faster and be easier to build. The only point of building a redstone computer is the urge of wanting to build one.

I started to ramble off topic a bit there. Here's a game I built for the computer, with three more circuits I'm thinking about using for an advanced redstone explanation thread.

http://www.minecraft...e-in-minecraft/

Quote from JSPRINGY

Whatever you do, I'm linking people to the thread

Thank you for that!