Making your own 4 bit computer from transistors

[Soncioz]

you explain for 5 minutes the full adder (which is to easy) and you do not explained the various components (LEDs, resistors, transistors) .... excuse my terrible English :)

[Ciddyism]

the adder in the end is not really a '4 bit computer' (as on the label) - 'calculator with one function' / 'logic function' would be more fitting!? (no clock --> no memory --> unable to use results and no OPCodes --> no ALU --> only add, ...)

But hey, since I wouldn't build a real 4 bit computer in hardware, I'm not complaining... just saying it...

(I would describe hardware in VHDL/Verilog, synthesize the files and put the bitmask on a FPGA board.... much easier and 50 MHz clock - or even more)

[mrmerino101]

@splendens memory is optional.

[johnny17616]

What texture pack is this?

[thebel89]

I was expecting tutorial how to make computer in MineCraft :D

[poonageguy]

minecraft

[dany080]

I watched the whole video,but you lost me second 1....

[Freaky99100]

This method doesn't work in minecraft apparently :( But my own method works pretty well and more compact XD

[MegaIhateit]

Now use this computer to make the same computer in minecraft... Then use the virtual computer to do the same thing. COMPUTERCEPTION!!!

[splendens]

Good work, but this is not a computer, this is a calculator. Where is the ram memory?

[nychold]

@splendens The term computer does not imply memory of any kind. It is simply a device which takes input, performs a calculation based on a given formula, and outputs the results. This 4 bit computer meets those criteria, so it is a computer.

[psickoO]

Now teach me how to make a quad core cpu

[drinkbudyXD]

i used to learn this in highschool,it was retarded cause the the teachers didnt know what the fuck they were saying,so i just showed up at tests,aced them and still didnt understand shit,i should have used the internet.. might have learned something

[CactusbIah]

Will it blend?

[DamiontheSpawn]

this is really usfull for mincraft omg nice thx a ton simoninns

[petehuws]

Is this narrated by Tony Blair???

[max137vzx]

Oh I think i see, are you just taking the carry from the far right and bringing it back to the far left? I am assuming that is what you mean by cascade.

[max137vzx]

At 2:39 for the picture. The "carry in" on the far left. Why does the diagram show that it is not coming from A and B? isn't its suppose to be coming from both A and B. The diagram has loops over those and doesn't seem to be connected to a source.

[max137vzx]

at 2:35 i need to take a break. Wow a lot of information very fast. Great video. I will be replaying over many many times.

[MrROFL92]

And what the hell dose this video have to do with minecraft

[youseftube1sfan]

the full adder give here is wrong, however it is right on your site. It does not calculate properly, let a=1, b=0, carry in=1 or 0 and it will give you a wrong answer.plz reply( i want to make it), and if you could please upload how to convert this into led output in base 10 (with diagram). Thanks

[ahmednematallah]

do you know how this could be applied to an IC?

[Geno11116]

The question is. Why would you make it?

[MRxManus]

Lol this sounded like some National geographic documentary xD

[kawless]

I'd call it a simple calculator, not a computer

[WinXPwhiz]

play COD on it

[CODMarioWarfare]

@WinXPwhiz Why would he downgrade it?

[TheChevroletnova]

can it run basic (from commadore 64)

[KaiOfBloodz]

play cod on it

[aganju]

is there a part list somewhere? i'm not sure what kind of transistors to buy. would this work on a breadboard?

[simoninns]

@aganju - Click on the link in the video description for more details of the project.

[jamespiperca]

If I recall correctly, subtraction is achieved by the same process except the number system is adjusted such that pos+ has 0 for left most bit, neg- has 0 for left most bit. Correct?

Anyone know of any links on this?

[simoninns]

@jamespiperca - Head over to wikipedia and search for 'two's compliment' - that's what the technique is called

[jamespiperca]

@simoninns Thanks for the reply.

Wondering if you hardware could be expanded by added a digital LED like in a clock-radio. Your leads to the individual LED could be inputed to the digital LED or am I offbase.

[simoninns]

@jamespiperca - You could connect 7-segment LED displays to it, but if you wanted numbers to come out you would need to design a binary to decimal conversion stage to control the display.

[leon2550]

@jamespiperca uh... i can't... (brain explodes)

[max137vzx]

@jamespiperca

This is stupid, I am curious as to where does the Or transistor connect to? More importantly where is the information stored or its final location?

[max137vzx]

@jamespiperca

Also what file do i use to open the schematics for your project?

[jamespiperca]

Great vid. It's been 20+ years since I studied this in university, but it came back.

[bidaddt69]

I made a 4 bit memory chip. from bigdatt69 if you have any question i can give you answers! matthewlawrence25@yahoo.com

[Nullatrum]

It's easier to use redstone

[thatguyofmanythings]

Was this made from npn or transistors? Or perhaps both?

[joazinho9099]

to much mats for me

[insonicbloom]

great content however in places the music at places takes over your voice and it's hard for me to hear what you are saying. I would suggest for the future that you use a sidechained compressor to duck the music abit when you speak so it never over takes.

[geekforlifevandc]

whats the music?

[pinche1994]

8O

[ahmednematallah]

Hi, this is great, i liked this video very much but where can I find more about this, maybe a multiplier or something more complex, also can you convert output to b10 and display it on an LCD (or LED matrix) or is this too complex

[noodlescracher28]

What programs can I use on a mac to open your schematic and pcb work? If mac is not possible can you refer me to a windows program?

[simoninns]

@noodlescracher28 - The files can be opened with expressPCB and expressSCH.

[Skypatter]

how many bits does a modern computer have ?

[ahmednematallah]

@Skypatter 64

[nuclearthelab]

Very nice, but as others pointed out this cannot, under any circuimstances, be called a "computer". Leaving cute wordplays with the verb "compute" aside. This is only a small part of the ALU of a computer.

[STULiAM]

Will this run Crysis?

[FadeToBlack181]

I want to use this with a QuadCrossfire 7970 configuration, will it bottleneck ?

[ahmednematallah]

@FadeToBlack181 you mean will the Quadfire config bottleneck it

[FadeToBlack181]

@ahmednematallah Nope, literally QuadCrossfire, as in Octafire, as in 8x7970s, though I may have to glue on some extra PCI slots.

[ahmednematallah]

@FadeToBlack181 Or even better an octafire of 7990s, you'll have to glue all the PCIe Slots, You're making your own computer,

I just wish the author doesn't think we're making fun of his computer

It's a great video and I really understood a lot of things about transistors from it

[ostapslobodian]

Really cool video for just your average person!

This really helps uncover the mystery of the computer and how some little scraps of metal can count

[RedVim]

You know, its kinda funny, how I learned about logic gates, adders and cpus in minecraft :p

[GrettyBoyCustoms]

where can i buy the parts (circuit board etc.)?

[95uptheirons]

What language is this?

[pufixas]

@95uptheirons

English?

If you are talking about programming language, then it doesn't have one, it just uses binary

[JDepptastic]

this is cool but; it's more like an adding machine to me.....

[RedVim]

@JDepptastic an adding machine IS a computer... look up "compute"

[empyrionin]

I'm trying to build this computer, I'm at the soldering part. In the LED section of the circuit, your schematic shows the BC547C transistors as having the emitter connected to the 10KOhm resistors and the collector to the LED, however, in the video, your computer shows those transistors inverted (emitter going to the LEDs). Is there a mistake in the schematic, or are you using PNP transistors for that section as opposed to the schematic?

[simoninns]

@empyrionin - All the transistors are NPN. In the LED circuit the transistors are sinking the 9Vs from the LEDs to ground. The LED is connected to the collector of the NPN and the emitter is connected to ground; this is as what is shown in the schematic.

[CubeRepublic]

Simon that's a really amazing video thank you very much. Very interesting to learn how transistors and gates work.

[jsthm52]

This is not a computer. Where's the program?

[waralotHD]

Can you hook me up whit some sort of a kit maybe?

Or at least the circuit board?

Thanks for the video btw.

[cjoenic]

the real issues is, how to use it?

[laeinc]

Why am I reading this guys comments in his voice?

[chunkymonky94]

Oh, never mind. I figured it out now. Lol!

[chunkymonky94]

I don't understand how you are counting in binary, please help me!! -.-

[ToyPitStop]

Very nice video!

[Itnecap]

you r a geniuos !!

[jrgreene89]

This is NOT a computer. This is a 4 bit adder. There is a huge difference. You good sir, are missing ram, rom, a command decoder, among many other important pieces.

[simoninns]

@jrgreene89 - 'compute' (verb): to calculate an answer or amount by using a machine - From the Cambridge English Dictionary

[laputahayom]

@simoninns

this is not a von neumann computer

[austinlcurr]

@simoninns Well, if you're being like that, computers used to be people who computed.

[pufixas]

@simoninns

'Compute' is not 'computer', a computer is a programmable machine designed to automatically carry out a sequence of arithmetic or logical operations.

Correct me if i'm wrong

[greekpa2]

@pufixas What do you think the first computers where? they where just ADDING machines. stupid cunt

[ThumbsUpBrah]

@jrgreene89 the self ownage is sad to read.

[xXDarkMidnightSunXx]

@jrgreene89 Burned. xD

[ndpratas]

@jrgreene89 I think you have the point. There is a lot more than just an adder in a computer

[Zknight7126]

What does the first carry in do?

[simoninns]

@Zknight7126 - The first carry is not really required; it was easier to leave it in though since then the PCB pattern for the 4 adders could just be copied 4 times rather than designing one specifically for the first adder.

[empyrionin]

@simoninns As far as I know, you can implement subtraction by using another digit (0 addition, 1 subtraction, a rudimentary decoder). When it is on, the second number is inverted with XNOR gates and the first carry is used to add 1 to the number to complete the 2s complement and then perform the addition.

[Sneak4000]

@Zknight7126 hi z

[Zknight7126]

@Sneak4000 Hi Sneak. You found this too?

[Zknight7126]

This could be helpful for building a computer in Minecraft, specifically to calculate things.

[enderzand]

my new school laptop

[TheCentralServices]

Can I run CoD on it?

[TheChevroletnova]

@TheCentralServices i think the -9 version

[noodlescracher28]

How much would you say was spent on this computer?

[nignocka]

The full adder you show in the video is different than the full adder in the transcript that you linked. I don't have much experience with logic gates but it seems as though the one in the video doesn't work. If your input for A is 1 and your input for B is 1 with a 0 for the carry in, the sum should come out to 1. Every time I work it out the sum comes to 0.

[simoninns]

@nignocka - You're correct there are a couple of mistakes in the video (this is mentioned on the web page). The versions on my website are correct.

[10yrubikscubeguy]

I discovered what brain tastes like while watching this as mine dribbled down my throat!

[mamooth]

Diodes for the OR gates are easier, IMO, but require more explanation, so meh. That's a really nice job you did there explaining it. This video can help SO many people, I'll be sharing it with friends! :)

[man4857]

@simoninns I think if you explained the Karnaugh Map, you'd have viewers less lost in how you arrived at the boolean functions. Maybe you could also use it to simplify your full adder and have less wiring to do so that way you can pave the way to do something bigger, like an 8 bit or 16 bit adder. :)

[gregerdaniel]

Will it run crysis?

[Munymuny200]

@gregerdaniel Probably not, the graphics card might not be up to par.

[oldtwins]

Great stuff. Need to require these type of lessons in the schools. Too many young morons saying they know about computers when they mean they know how to click through a website. Learn some real computing, please.

[Photoshop211]

?!?! im confused u lost me when the first graphic showed :P

[Redickja]

can i play pokemon on it?

[dinetsandrew]

Tell about about ROM whith flashing transistor hehe.... may be Magnetic-core memory hehe

trigger register ram.... nostalgia

did you know, subtraction also use adder and only adder ? hehe

[UprootedEagle]

Building it in Minecraft with the help of this video :D

[leighstephens74]

This is a "boorish" video. =p

[skatingrock2]

now lets make it in minecraft

[SuperItchii]

Kjell & Kompany!!!

[BrandonRDillon]

i did something like this in my computer internals class but instead of leds we used 7 segment displays, it was a really fun class to be doing this kind of stuff

[0987654321134]

@BrandonRDillon please tell how did you do it using 7 segment displays i have been trying for long.it would be of great help.

[k3xa9e7cz8b]

The entire procedures might be a little bit complicated, but it is actually fantastic! Great job! I will try to make my own! Thanks for your invaluable help!

[SuperBunkerbuster]

Wow, very impressive work, congratulations ! A litlle question : what's happening if you try to add 12+6 (or anything with a reasult greater than 15) ? I guess it will overflow the... hum, "power" of this calculator but what the LED would indicate ?

[simoninns]

@SuperBunkerbuster - A 4 bit adder has 4 bits of output and 1 carry bit so you can't overflow it with 2x4 bits of input: 1111 (15) + 1111 = 11110 (30)

[TheTimmyewrard]

the cpu can also subtraction

[TheTimmyewrard]

du meinst cpu :central processing unit aber gut :D

[ignas2526]

I must note that adding illustrated here is one out of like 10 functions basic Arithmetical Logical Unit does. ALU is one of the essential components of Central Processing Unit, but it cannot do much on its own and relies on the rest of CPU parts for getting data and sending it to the right place. CPU is one of essential components of the computer, CPU requires at least storage(RAM, HDD, SSD) to operate and GPU, Keyboard, Display etc. to display something.

[TickyTack23]

This all was explained to me 15 years ago from a book at Radioshack. What ever happen to these books?

[Aspecsi]

Wohh nice really nice good work

[Gunbardo]

@XxDoubleXProductions You know, your sentence read in layman terms makes no sense but in the eye of a technician, it is understandable! Lol~

[Gunbardo]

I still dont understand the not gate... How can information be inverted? What does it mean, are the atoms stopped from moving forward in a circuit from the point the NOT gate is applied? And vice versa?

[8bitRemakes]

@Gunbardo

There are two transistors within the NOT gate, one of them responds when there is no input, the other when there is. :)

[Ibringthetruth1]

Is this the lecture superman got when he was in the spaceship flying from his destroyed home planet.

[clawproductionDX]

SO....MUCH......MATH!!!

[stri8ted]

This is the closest Ive gotten to understanding how the stuff works. I would love to see a slowed down better explained version. Cheers.

[simoninns]

@stri8ted - If you follow the link in the description you will find a complete transcript of the video complete with diagrams and explanations; glad you liked the project!

[ilikecoding]

@stri8ted What do you want to know?

[XxDoubleXProductions]

we use 1 or and gate and not or and gate for A1 not B1 and 1 is not 0 so I make no sence

[ElectricMuffinDude]

Kjell o Company någonting säger mig att du är från Sverige! :)

[snomimons]

my mind = blown.

Thanks for upload.

[murmurrer]

Interesting, but the music made me dislike it and move.

[ickieestes12r]

This video went viral on Turkmenistan

[ActiveStorage]

people in the 1930s would love to get their hands on one of these

[DGMRuadeil]

Awesome, this makes me want to build one now!

[Pagweb]

I've being looking for a video like this for years. I've always searched for "How to make a computer", but I got was videos of teenagers assembling computers with already-made parts. Is not until recently that I look up transistors that I finally found this video on the suggestions. Anyway, thanks for sharing.

[3Deity]

I expect within 20 years you'll be making something called an 'iPad' :o)

This is a really refreshing video - always good to reacquaint yourself with logic gates. I used to program micro computers 30 years ago and recently thought about getting into PIC processors but logic gates leave me cold - Where do you start? From that point of view this video is priceless!

[hassans111]

5*

[pghg022]

hey your video is great and i love it

can you tell me where can i get a schematics of a full adder and subtracter with the least number of logic gates used??

[ChildsViewReviews]

Before I try.. Is it capable of running a PONG game? Even with no scoring system?

[AdilsonAlmeidan]

this music is scary

[presa1200]

hi, what's A & B and what happens if i move my mouse or click an icon?

[Morelloo1]

my god. flashback to computer architecture classes in uni.

[One4TheTechnoGuy]

But will it run crysis?

[ilikecoding]

@One4TheTechnoGuy It can even run the Matrix.

[One4TheTechnoGuy]

@ilikecoding Wow! Do you think i can run the matrix

*2x Xeon Processors

*128GB RAM

*3 nVidia Tesla C2070

*nVidia Quadro 6000

[yildiralp]

there is an error @1:07

1 + 1 = 0c1

[MarkusQu]

WOW, it boot up faster then my iMac :)

[TOMHCKY]

Where did you get that from?

[chieftech100]

OMG



[jupannrone]

great tutorial !

[FuzzDog525]

Best ever explanation of how computers work. Thanks man.

[Zee96969696]

does he have to talk so fast and unclear? I never heard half the words he said in there... jeez

[larsaaaaaaaa]

@Zee96969696 I liked the way he talked.

[furChrist]

That was very cool. Thank you for sharing your knowledge.

[Quaaludedude714]

Eagle CAD works great & best if you go for 8 bits :) QC

[livekid24]

Nice.Very intresting

[Mercurycartoons]

What Software do you use for making schematics?

[simoninns]

@Mercurycartoons - I used ExpressSCH for this project, but these days I'm using Eagle CAD which is more powerful

[rtty21]

@simoninns like a boss

[AwesomeFace50]

Now.... Squeeze that into a 1X1 inch plastic thing XD

[LapZGaming]

like this if you thought this was a minecraft computer tutorials

[andruha11234]

wow.. finally someone explains computers on a level that makes complete sense from the hardware point of view.

thanks

[normskilight]

Could you please explain part of the diagram of the Full adder at 2:35, if you follow the line straight from the carry in, it splits and one is inverted, they both then lead to an And gate. What situation does this And gate operate, as I must be missing something on how the carry can be simultaneously on and off? The diagram provided in the link for the Full adder is different. thanks in advance.

[simoninns]

@normskilight - many moons ago (and now buried deep in the comments) I mentioned that there were a couple of mistakes in the diagrams show in the video. The latest (and hopefully completely correct!) diagrams can be found on my website. Just follow the link in the video's description. If I'd had know just how many views this video was going to get I would have been *way* more careful :) You never can tell I guess!

[nignocka]

@normskilight I noticed that too. I tried to work out what would happen with different inputs using his diagram for the full adder. It doesn't work out for me. If your inputs are A = 0, B = 1, and carry in = 0, the sum comes out to 0. it should come out to 1.

[normskilight]

@nignocka the video maker responded to that question, he informed me that there is an error in the video, however if you see the link provided in the description all instructions are correct.

[TheHamidakram]

IT WOULD BETTER TO DEMONSTRATING STEP BY STEP PROCESSES WITH THE AID OF LABELLED DIAGRAMS

@HisMight1

Nein. Ich komme aus Australian so mein Deutsch ist noch nicht so gut.

And I don't know much about Germany lmao