A 1 bit ALU explained

[@spookeylordzey8432]

You are an absolute LEGEND, I've been googling about this and trying to make it for hours and I even fell asleep and woke up the next day and kept googling and searching for a tutorial or an explanation for this, this video is the best explanation I've found, it's easy to understand and there's no "abstraction" or some mystery black box, thanks.

[@L490sr]

😂

[@mark-felixmumma890]

Thanks! I had some trouble figuring out how the decoder makes the ALU choose what operations to do. Your video explained it well. Keep it up :)

[@Peter-xs2mu]

To me, the video looks like it's starting in the middle, with some introduction missing. The introduction would read something like "This is a one-bit ALU, having the folloing four functions: (A and B, A or B, A+B and the fourth one). The four functions are selected by way of the decoder (I'm still not sure of the settings) etc. Othewise a very interesting movie.

[@Djake3tooth]

In the decoder part, starting from the top, the enable lines turning on correspond to 0 (F0=0;F1=0), 2 (0;1), 1 (1;0) and 3 (1;1). Then the corresponding 4 functions are A and B, A or B, not B and A+B+CarryIn. Only the fourth function turns on CarryOut if A+B+CarryIn is 2 or 3.

[@LeonidSaykin]

I used two half adders and the or gate to build my full adder and I am wondering what the enabler that comes out from the decoder supposed to block

[@PeetHobby]

It's possible to make a 2 to 4 decoder two inverters instead of four, put one inverter on F0 and one inverter on F1, then you have four signals, normal F0 and F1 and you have inverted F0 and F1, with that you can make 0 0, 0 1, 1 0 and 1 1 for the AND gates inputs. Just my 2cents. :)

[@aboodsbahi9568]

Best video for A 1 ALU explanation!! Thx

[@Funkyfurnwood]

Thank you for the help and everything, but when is the next cat video?

[@pinklady7184]

You should check out app EveryCircuit. It does circuit simulations. That has helped me understand electronics.

[@empatikokumalar8202]

Is this same scheme used for the next bit? How is the carry count used in this case?

[@sammob1772]

Video from 7 years ago saves my life, what a fun life :D

[@neosurrealist]

I'm glad!

[@duality4y]

Why would you want an enable on the Carry out? oh never mind now i look closer that enable ties into the sum output enable, so with that enable you select the full adder. it looked a little confusing to me. would have been clearer (atleast to me) to put instead of those two and gates one and gate after the or Gate for the carry out.

[@TheRojo387]

No sensible ALU will be set up this way. Look at the sheer gate depth!

[@hezi78]

code for it in verilog?

[@adam-nq3qv]

doug demuro makes digital logic videos?

[@AntonioSedicina]

Thank you for this video. I'm studying this for University.

[@nadiaatz]

best explanation i have seen !

[@rawanq95]

is ALU always contain the same by that i mean (decoder , full adder , ENA,ENB , INVA , logic unit ) even if it's 4-bit ALU ?

[@christio02]

Great video!

[@dccglobalengineering]

Good job 🎉. Thank you.

[@freddygonzalez6711]

Can you share your files?? I want to test it in Logisim. Thanks for your video.

[@talhafarooq5246]

pls share its simplified version using Kmap

[@neosurrealist]

I’m pretty sure this is going to be way more complicated with a K Map

[@aschemusicreations]

Thanks man

[@martinhabsburger4929]

How can A and INVA both be 1?

[@neosurrealist]

They can both be a 1 if the ENA is a 0. Basically the ENA disables A so that whatever goes into A will always result in the first AND gate being 0. (5:16) I.E. if ENA is zero then the inverse of A is 1 regardless to what you send into A.

[@caesarzheng3815]

well explained. but it's really hard to read those lines

[@LOKSTED]

I built this in Minecraft!

[@tonmoyroy2157]

i need 2bit alu diagram . plz help

[@neosurrealist]

Send me a PM with the diagram.

[@somerhimpson8338]

Thank you!!!!!

[@charlesmcboy445]

Just say is a selector man!

[@michaelsanti1610]

brilliant.