Sometimes, whenever i'm watching these videos, i'm normally at least mildly interested in the subject matter. Then I suddenly remember that in order to watch this video, this thing that he's described in 8 minutes is happening about a foot away from me, millions of times a second, near the speed of light, and it just blows my mind. This channel just does these things to me sometimes.
It'd be cool to have all the "previous videos on how memory works" in a play list. I think I remember watching (most? of) them, but it's easier to wrap ones head around the various topic when seeing the entire video, not just a 15 second recap =)
Well, tomorrow I'm going to write an exam in "Technischer Informatik" which is German for technical computer science. Good thing I checked my subscriptions on UA-cam before starting to study because the content of this video will also be part of the exam :-)
Hi, I don't think I'll ever forgive UA-cam for removing 'annotations' which is how these all used to connect together - I just went through I don't know how many pages of videos to try to remember which came first! - pretty sure it's this one - hope so ua-cam.com/video/XETZoRYdtkw/v-deo.html -Sean
@@Computerphile I also miss the annotations feature. Google's enshittification continue to accelerate- android, gmail, youtube, chrome, Voice, all of it. I encourage you to add/pin that URL for part 0 to the vid description. Maybe even update the URL to include (Pt 0) in the name. Maybe make a playlist with everything in order.
3:50: Why not connect both gates to the clock, and just invert one them? like use a common emitter NPN transistor to invert? Unless having both clock pins at 0 is also a requirement, why bother with that 6:35 logic gate stuff?
It is a requirement that both clock pins be 0 at times. The inputs and clock can't all be changed at exactly the same time, so you need to be able to disable writing while all the input lines are prepared for the next write.
My interest has been peaked too many times without action. I want to create these circuits for myself. Before diving into breadboards and transistors is there any software out there that will let me create these kinds of circuits that is easy for beginner? If it was online that would be a bonus!!
Look at a program called logisim, simulates much faster than something like minecraft. You could build whole CPUs with operating systems in logisim. I have some minecraft and some logisim stuff on my channel.
This is okay for a 2-bit memory, but for a large (deep) memory I'm pretty sure you wouldn't want to implement independent addressing logic for every memory location. Presumably, there's a smart way to share logic to minimize the number of transistors used. This must be a solved problem... and I bet the answer is interesting, but so far my googling skills are failing me.
Me too, I can't find neither IRL nor Minecraft videos explaining how to use muliplexers to address large memory. What I know so far is that a binary numeral must be decoded to select a memory cell. 2 multiplexers are used, 1 selects a row and the other a column. They are connected as a chain (in series) so the row mux selects an entire row of cells, creating a "new" fake memory whose size is the square root of the original memory. This memory is WAY smaller, allowing the column mux to use less circuitry to select a single cell. The "cell" can be as large as you want, but all cells in memory must have the same size. Modern computers use octet cells (usually called "Bytes"), but in MC it's easier to have single bit cells, even though it's slower
When he finished with the 0 and 1 flipflop I was like, "but those only correspond with high and low on the A1". So how are you going to do more than 2 flipflops!! you can't have more than high and low state on the A1! And then he was just like "so we add A2"... And suddenly it all clicked for me and now I understand memory addressing.
Wouldn't this implementation have bad clock skew for reasonalbe size memories? I'm also pretty sure you'd have issues with the clock input glitching. It seems like if you wanted to go with a purely digital example of memory that it would be less fraught to use 2-to-1 multiplexer feedback.
Should have been an OR gate. A HIGH on the WR line holds the Clock input HIGH until the Address line is stabilized, then the single address line should be inverted to decode the address "1".
Try out prison architect. They coded logic into that for controlling doors etc. Someone ended up making an 8bit I think it was virtual computer with it :)
+Oliver Utriainen What? I don't mean to be rude but have you seen his face? He looks like the computer science version of Andrew Lloyd Webber. Not saying he's unlikable, I enjoy the videos with him a lot but I ain't so sure about the apperance thing :'D
That second And gate I think is unnecessary, the first one is ensure the data only changes when the write line is asserted so no need to do it again, because theres only two flip-flops, just invert the output of the first And gate. Also I'm pretty sure real systems don't do this. The memory locations are literally stacked on top of each (into a physical rectangle) other so it does X/Y decoding instead.
Sometimes, whenever i'm watching these videos, i'm normally at least mildly interested in the subject matter. Then I suddenly remember that in order to watch this video, this thing that he's described in 8 minutes is happening about a foot away from me, millions of times a second, near the speed of light, and it just blows my mind. This channel just does these things to me sometimes.
ok?
It'd be cool to have all the "previous videos on how memory works" in a play list. I think I remember watching (most? of) them, but it's easier to wrap ones head around the various topic when seeing the entire video, not just a 15 second recap =)
??
@@Triantalex!!
Yeah where the heck is it?
Well, tomorrow I'm going to write an exam in "Technischer Informatik" which is German for technical computer science. Good thing I checked my subscriptions on UA-cam before starting to study because the content of this video will also be part of the exam :-)
The animated schematics are neatly done. :)
this is so interesting to me. I love learning this type of stuff! thanks guys
0:38 A common mistake, it's not "between nought and fifteen" but must be "from nought to fifteen", the first contains fourteen values (n>0 ; n=0 ; n
0:00 He says there was a previous video to this one. What's it called and where is it?
Hi, I don't think I'll ever forgive UA-cam for removing 'annotations' which is how these all used to connect together - I just went through I don't know how many pages of videos to try to remember which came first! - pretty sure it's this one - hope so ua-cam.com/video/XETZoRYdtkw/v-deo.html -Sean
@@Computerphile I also miss the annotations feature. Google's enshittification continue to accelerate- android, gmail, youtube, chrome, Voice, all of it. I encourage you to add/pin that URL for part 0 to the vid description. Maybe even update the URL to include (Pt 0) in the name. Maybe make a playlist with everything in order.
3:50: Why not connect both gates to the clock, and just invert one them? like use a common emitter NPN transistor to invert?
Unless having both clock pins at 0 is also a requirement, why bother with that 6:35 logic gate stuff?
It is a requirement that both clock pins be 0 at times. The inputs and clock can't all be changed at exactly the same time, so you need to be able to disable writing while all the input lines are prepared for the next write.
Are we going to see a video on the "rowhammer" problem?
Phil Hibbs That sounds like a League of Legends problem.
My interest has been peaked too many times without action. I want to create these circuits for myself. Before diving into breadboards and transistors is there any software out there that will let me create these kinds of circuits that is easy for beginner? If it was online that would be a bonus!!
cedar logic simulator maybe.
I believe you can do a lot of this in Minecraft - hoping to cover that at some point >Sean
Look at a program called logisim, simulates much faster than something like minecraft. You could build whole CPUs with operating systems in logisim.
I have some minecraft and some logisim stuff on my channel.
***** Minecraft.... You mean the game that everyone is playing. That I did not know.
You can do it in Minecraft.
This guy spent 8 minutes explaining a simple demultiplexer without ever having uttered the word, "demultiplexer"
😅bytctttc vcyou 😢 😢cy😢yv try c tct😮c ccw🎉
??
This is okay for a 2-bit memory, but for a large (deep) memory I'm pretty sure you wouldn't want to implement independent addressing logic for every memory location. Presumably, there's a smart way to share logic to minimize the number of transistors used. This must be a solved problem... and I bet the answer is interesting, but so far my googling skills are failing me.
Me too, I can't find neither IRL nor Minecraft videos explaining how to use muliplexers to address large memory.
What I know so far is that a binary numeral must be decoded to select a memory cell. 2 multiplexers are used, 1 selects a row and the other a column. They are connected as a chain (in series) so the row mux selects an entire row of cells, creating a "new" fake memory whose size is the square root of the original memory. This memory is WAY smaller, allowing the column mux to use less circuitry to select a single cell. The "cell" can be as large as you want, but all cells in memory must have the same size. Modern computers use octet cells (usually called "Bytes"), but in MC it's easier to have single bit cells, even though it's slower
So, for each clock cycle you have to rewrite all the values that are 1, right?
When he finished with the 0 and 1 flipflop I was like, "but those only correspond with high and low on the A1". So how are you going to do more than 2 flipflops!! you can't have more than high and low state on the A1! And then he was just like "so we add A2"... And suddenly it all clicked for me and now I understand memory addressing.
Is that desoldering gun behind you any good ? I was going to get one off eBay.
Yes -- There's an EEVBlog review video on UA-cam somewhere (EEVBlog #542)
thats for the newer one tho. This one is the older one was wondering if they are same internals
So this is part 1 but is a follow up to an earlier video. Part 0? Where is it?
Brady, can you please do a video on assembler?
Wouldn't this implementation have bad clock skew for reasonalbe size memories? I'm also pretty sure you'd have issues with the clock input glitching. It seems like if you wanted to go with a purely digital example of memory that it would be less fraught to use 2-to-1 multiplexer feedback.
Can anybody tell what level of my math and computer stuff classes studies must I be on to undertand what's going... please?
you need to know basic electronics engineering....
Should have been an OR gate. A HIGH on the WR line holds the Clock input HIGH until the Address line is stabilized, then the single address line should be inverted to decode the address "1".
Flipflop is used in ram or rom
Try out prison architect. They coded logic into that for controlling doors etc. Someone ended up making an 8bit I think it was virtual computer with it :)
This guy has such a pleasant appearance!
Who says polyester went out of style 40 years ago?
+Oliver Utriainen What? I don't mean to be rude but have you seen his face? He looks like the computer science version of Andrew Lloyd Webber. Not saying he's unlikable, I enjoy the videos with him a lot but I ain't so sure about the apperance thing :'D
I would still like to know how the nor gates and and gates work on a transistor level
That second And gate I think is unnecessary, the first one is ensure the data only changes when the write line is asserted so no need to do it again, because theres only two flip-flops, just invert the output of the first And gate.
Also I'm pretty sure real systems don't do this. The memory locations are literally stacked on top of each (into a physical rectangle) other so it does X/Y decoding instead.
If you just inverted the output of the AND gate, you would always write in the zeroth memory address whenever the write signal is turned off.
Oh yeah
Lttlemoi is right.
This is getting ridiculous. You are going thru my last year's coursework.
ADORING FAN
In the preview image for this video it looks like he's singing into a tiny microphone.
QUESTION: How does simultaneous swapping work in an edge- triggered d flip flop?
Nice
I have an assembly test in 2 days
@Oliver Utriainen I watch almost just to see him, he is very handsome and has nice lips 😃
How much memory could I allocate between his teeth?
First!
to get the D
first comment!
"D in" XD
How old are you?
Please can you marry me?
Is it me or does these foreign accents explaining stuff like this make you sleepy?