the quality of the content is over the roof on this channel. I really appreciate the smooth transitions, consistency of explanation, no steps are skipped, everything is explained. amazing, Ben, keep up the great work!
if he made a cpu and a basic web server internet in the same year (2017-2018) that is super super freaky that is literally my 2 big projects i have been doing
Samuel Miller funny, I also worked on some pc and OSI model simulations 2 or 3 years back. To see Ben make videos about both really brings back memories. Its basically a practical implementation of the course I followed called Computer Architecture and Networks.
Dude, that's exactly what I thought of as he casually laid down his first blue wire, perfectly cut to length. "And... we'll just add some happy little wires here..." Mr. Eater, the amount of planning you must do to make it look so easy is formidable!
The errors he makes along the way are also prepared in advance, I'm guessing. The guy is very skilled, but he also goes in depth enough so that a newbie can get into the videos, understand them, and avoid common pitfalls. Really great vids.
The thing I really appreciate about your videos is the "stream of consciousness" style where you let us see your thought process and problem solving internal voice. I learn so much more hearing you think aloud through these problems.
Ben, I think you're doing a really great job teaching about some of the fundamentals. The importance of having at least a basic understanding of how all the components of a system work is often underestimated. People want to skip over it to the tasty stuff and then find troubleshooting hard. Keep up the good work!
By far the best fundamental communication protocol explanation I've watched. I've finally begun to learn to stick to one task a bit longer (ok.. OK..a few tasks at once), but I really want to try this out myself just to see it first hand....I must not get distracted.... I must not get distracted... where did I put that other nano...crap -Jake
I love how you constantly make us think we’re ahead of you, thinking “wait, that won’t work”, which is exactly what you intended of course. Great teaching, Ben.
I love the way he introduces a problem, calmly explains what to be expected, and how close everything is to reality (not just in an academic way). Then he presents us with a solution and an explanation on why/how it works. These videos are really educational and informative, and he's truly a great professor!
You are RUclips evolved. This is the first of your videos I've watched, and I'm absolutely thrilled to go back and watch the rest of your stuff. I hope to have your teaching skill one day. Thank you.
The coolest thing here to me is the way we're all sat watching this via a method which is just a few steps away from what he's demonstrating. Data in, data shoved down wire, data out. These are tests and lessons you can do in your own home, and gain a real appreciation for the fundamentals behind how this stuff works.
sort of, but if electrical engineering was a language, I think it would be C++, because electrical engineering is by no means a scripting language, so LEDs are more like: std::cout
27:10: It's very clear that since ! is ASCII 33 (00100001) and " is ASCII 34 (00100010), it's just the final bit that arrived a little too soon, so the delay was almost long enough but not quite.
I've spent more time than I care to admit on RUclips over many years. This may be the best electronics/programming video I've ever seen. Truly a work of art.
31:30 A huge concept just sank in and solidified to memory at this moment. I love your videos because they break down complicated concepts into understandable steps and let the viewer follow along and make the connection naturally. 34:05 To demonstrate how much this is actually makes sense: now I'm thinking about how you would add a second data line and modify the code to alternate which one the receiver reads from at a given moment. Obviously you could increase the transmit rate, but for some reason the former seems more interesting, at least for learning.
This video is a good overview of communication. Note: As you a measuring the crystal oscillator you are changing the circuit. (It's a very delicate circuit, I'm amazed it even works when measured.) Even the worst oscillators will likely not be beyond 100ppm. To improve NRZ you can do oversampling at the receiver.
I was expecting to see some phase locking of the timers each time the NRZ state changed, or some oversampling or some other asyncronous tricks. But nope, just a clock line.
I love this guy, HE is to the point no Special video effects, no look at me " I'm on yout tube" type of videos like others do. He is to the point and knows what he is talking about and best of all he is not presumptions. Ben you are the best out there.
I’m an old hand with this stuff, but I’ve found these videos quite inspirational. I find myself tinkering much more than I used to before I discovered them. Colleagues that I’ve shared them with feel the same. Keep uo the excellent work!
I'm sure you've covered this before in another video but I appreciate the way you describe these topics. You allow the viewer to take the path that someone might take if they didn't have a priori knowledge of computers. It not only helps someone learn the problem but hopefully they come to appreciate how elegant some of the solutions are.
Blown away by the elegant way on which you explain this. Everything evendown to your hand gestures is so great. Love how you break this down to such a basic level.
It's actually not that hard. The extra processing required (in the loop) on the receiving can arbitrarily take too much time, whereby the receiver is getting only part of the signal, therefore the bits are a little off, and then you get jumbled characters.
@@codetutor6593 I love stuff like this. I've watched some more videos and all of this is making much more sense. I was initially making fun of the garbled characters, but i think i understand why that happens now.
I love how at first I was screaming at my screen that his is now how you do this... and then you fixed it, showing both common beginner mistakes and a feasible solution to it. Good balance on the detail and being engaging.
This video is a MUST WATCH for all new Elect Eng undergrads doing communication major. Save the lecturers lots of explanation. Even a you kid can understand.
It's not just you. Ben has a gift of conveying knowledge in a really accessible and engaging manner. Even though I know much of the stuff he's talking about I still find his videos very interesting.
Completely agree. It's not just the content. His delivery of the subject matter makes the difference. I've been an Electronics Technician since 1974 and have seen only a VERY small number of tutorials that match the quality seen here.
Using strlen() in a for loop (at 3:10) wastes a lot of processing time, because for each iteration of the loop, the processor is stepping through the entire string and counts until it gets to the end. For a string whose length is constant, you can save a lot of time by saving the length in a variable, and using that in the loop. (seen in the outer for loop in setup() in the transmitter code)
Ben Eater, this videos are insanely well made! Everything is SO clear. Perfect flow of speech and videos. The level of tidiness on your circuit layouts with straight and pre-prepared wires is unparalleled, you make electronics look as simple as assembling LEGOs, well done!
Sunday morning, turned on my computer sipping a warm coffee and saw a new video from Ben. Loved it. I like the way how you present your videos. For example, you demonstrate the data reception error due to async transmission, and thus creating a learning moment and then coming up with a solution. Great, I'm looking forward to more videos.
I remember back in the 90's i got my first PC and a cross assembler to write code for my C-128. Since floppy disk formats were incompatible i hooked the PC parallel port up to the C128's userport. I quickly learned that i cannot do without some sort of handshake. But for some odd reason i did it the other way around. The userport's current output is to low to pull the parallel ports data pins to its level except for one (i think it was the paper sense line). I had the commodore sending the clock pulses and the PC would send a byte via parallel port to the userport. I had a little machine code routine on the C128 watching for a ready signal from the PC and then start to send the pulses. First 2 bytes were the number of bytes to transmit. One variety of the receiver code would also start the program right after finishing receiving it. Good times :)
My brain went nuts at 31 mins when you explain the clock channel, all the small electronics where I have seen the data and clock pins makes so much sense now. What a cool project and way of demonstrating data encoding.
Your videos helped me understand bread boards. In school, I was never tought how they work, just told where to put bits with no knowledge of the circuits or how they work
@@b4l1x the condition is re-evaluating every time, including computing the length, which is in the order of the length of the string if the compiler didn't optimise (which many do for strlen)
Ben, this is a great video. I did something similar when I taught a data communications class as a clinical/adjunct professor. Your demonstration is better than what I did. I was looking for this thread; I spotted this issue when I watched this morning. Ted, you are completely correct. As written, this code fragment is O(n^2) in the length of the message. However, might I suggest for pedagogical purposes (many viewers don't have our experience): msg_len = strlen(message); /* Could be written as: for(int byte_idx = 0, msg_len = strlen(message); byte_idx .... ) */ for(int byte_idx = 0; byte_idx < msg_len; byte_idx++) { char tx_byte = message[byte_idx]; } Balazs Oczot, unless the compiler did the above optimization, this fragment is, indeed, O(n^2). C _guarantees_ that the conditional in a 'for' loop will be evaluated every iteration. strlen() determines the length by marching along the string searching for the null character, '\0', that marks the end of a C string. So, finding the length of the string is O(n). Because the for loop is executed n times and at each iteration the length of the string is calculated, this fragment is, as Ted stated, O(n^2). Your point regarding pedagogy is well taken. Simon, you are absolutely correct. I worked for a large, well known company, as an industrial mathematician doing queueing theory and performance engineering. A large project was nearly cancelled because it didn't meet performance requirements. None of the software engineers could find the problem. I never knew the exact details, but I guess perhaps 50 staff-years of work ready to be flushed down the toilet. One of my colleagues and I were given the task of finding the problem, else the project would be scrapped. It turned out that this exact problem, buried at the bottom of several nested loops, was the culprit. After fixing this, just as above, and recompiling, the project went from failing abysmally, about sixty times slower than required, to exceeding the performance requirements by about 50%. I often wonder how many projects are saved today simply by throwing more or faster silicon at it, rather than finding the root cause. Be well & Best regards, Gottfried
As a network technician with little to no knowledge regarding programming and circuits, I can figure out some of the quirks and theories surrounding the network fundamentals by seeing this material. Now I'm much more interested on studying circuits and low-level programming thanks to you! God bless!
His soothing voice coupled with his ability to break down such a complex topic makes his videos enjoyable. I have a bachelor's in computer engineering and 30 mins of Ben Eater has made me understand more about data transmission than 5years in the university. I honestly never fully understood what the point of the clock signal was before now!
This is the correct speed and detail level for viewers interested in the subject matter and basic familiarity with electronics and programming. Presentation is excellent. Very professional.
Well done. I think your patience to give a complete explanation without leaving details up to the listener is very valuable, since I assume this is for the beginner. You have to get the details at least the first time. Excellent visual recording of your presentation and the drop-in windows add a lot. Can't wait for the follow-ons.
woah same, I'm just an experienced software engineer and haven't really messed much with hardware but I somehow knew where and why stuff will break :^)
im so glad i found this channel... love understanding low level stuff, and i dont understand how there are so many programmers that go through their days writing code and not understanding these low level basics. i guess its just the way my brain works
Your video is one of the best about basic communication. The thoroughness of your explanation is amazing. I'd be more than happy to have you for teacher when i was taking basic comm classes.
Excellent walk-through and explanation!! Basically creating an I2C type interface. As a beginner programmer with mcu's and jumping head first into this coding/designing world (I have yet to go through the arduino tutorials), I find this type of teaching very informative and easy to follow. I learn much faster by working with "real world" applications, rather than the simulated pseudo ones that are the tutorials (hard to make the cross applications). This type of teaching helps me bridge those gaps. Much appreciated and subbed! 😁 Look forward to part 2+!
40:00 you also did that , i was also thinking about that. ' what if computer read on and off as single and any particular time when tx send 1 and then connection loosed so rx will not get same thing but 0 instead 1 so !! You covered that
Couldn’t stop watching although I already know this stuff. Great way of explaining things, building it up gradually and also showing the path from overly simple ‘non-working’ solutions to (probably) why the I2C bus is what it is.
Fantastic work, Ben! Loved your explanations and the way you built it step by step. Planning to build this to show my students how physical data transmission works.
Funny thing is I need to transmit data from a bunch of Arduinos (Nano) to a single 'central' Arduino (Mega, it will most probably ask for the information so I will multiplex through the Nanos) for a school project. I was thinking about the built-in shiftOut and shiftIn functions, but they wouldn't work as I wanted to. This videos will be extremely helpful so I can get this little project done.
Using the method shown in the video is good for illustration purposes, but, you'll be much better off using SPI/I2C protocols. It's much easier to use and a lot more reliable. Not trying to discourage you from building your own transmission protocol from scratch, it's a pretty awesome thing to do. It's just that your comment "they wouldn't work as I wanted to" made me feel like you tried using the inbuilt functionality and failed, and now think that they are not capable of proper reliable transmission. That's not the case. SPI and I2C are specifically made for communication between multiple devices. Thousands of engineers have worked on building those protocols so there is not much that they can't do in their domain of functions. So yeah, building your own communication system is cool and good for understanding the basics, but, at the end you are much better off using the already in use protocols.
Oh, I didn't try to use the shiftIn/Out functions, I just looked the code of what they actually do and it's kind of what I want but not exactly. My idea was to 'create' my own protocol, I don't have the idea completely structured yet, that's why I try to avoid (in a certain way) SPI (or other serial protocols). Maybe it's the idea of having complete control over what I do bit by bit? I don't know, I'll probably end up copycating it or something :d
Just use the UART - you can combine multiple serial data sources into one with a simple AND gate. So long as only one ever transmits at a time, you will need a protocol to avoid or handle collisions.
Use I2C if you need to communicate with multiple Arduinos with the least among of wires required, since the serial protocol is build into it. Define the addresses of the slave Arduinos, and use your master Arduino as the main one to communicate with them.
This is sort of the best ever explanation of digital communication I ever have heard. It was and still is my daily bread, but one thing is using it, one thing is to explain it. Very well done!
At @22:50 , line strncat(), when you're sending infinite zeros in the demo right after, wouldn't you be overwriting the message char string passed it's allocated 16 chars? So pushing zeros beyond the end of message?
In C, strings are null-terminated, so writing a null at the end of the message just "overwrites" the null that was there anyway and doesn't make the string any longer. But it would definitely be a problem if it kept receiving more data (beyond 16 characters). So you're right that if we were doing anything serious, we ought to check for that.
25:04 Looks like a classic case of the Satanic possession bug. I'd recommend a code exorcist but I imagine Ben will purge the spirits by the end of the video.
Thanks for the video. Your method of teaching micro electronics is the best I have seen so far. The way you play dumb by letting errors happen and then fix them is such a teaching style which can only be done by a genius.
I like the tricks you're using to hide some of the complexity that could distract from what you're trying to teach here, such as: - using strncpy to copy 1 byte, which conveniently interprets a 0 as an empty string - setting update_lcd = false immediately after checking it, to minimize the effect of the TOCTOU race condition (and then updating the whole LCD on each loop iteration so that if you trigger the race, so it still doesn't end up corrupting the display)
Hey Ben, Did you know that scope you have can be unlocked to twice the sample rate and have some other additional features through an online key generator? It was a pleasant surprise when I found out mine could do way more when it unlocked all the features.
I always like the way you explain underlying concept through examples and problem scenarios. Nice way of explaining effect of unsynchronized clocks on data transmission.
i like the way you present information. I've opinion of what extra info might be presented: you started (8:40) with framing bit which is start bit in UART (or maybe link to that video) but you ended with clock which is closer to USART... also i think it was nice to remove the delay in transmitter (although i think it will not affect because delay in LCD library is big already) so maybe print after recieving everything.. and its nice to briefly talk about why the wires are twisted ;).
Have you tried simply setting the bps high enough to start seeing 'natural' errors? It seemed kind of odd that you mentioned it but didn't test it considering how easy it ought to be.
With the clock, this design will be error free up to rates well above the speed of an Arduino. That is, if I removed the delays altogether, you'd just see the correct message appear "instantly" (at least to the eye) on the other side. The "natural" errors I mentioned start to show up in wireless communication (where there's more interference) and at very high bitrates (multiple millions or billions of bits per second).
You could also introduce errors by adding noise to the transmission line. This could be done by a white noise generator and a restive adder circuit. By adding noise and messing with different coding schemes, you can attempt to get close to the Shannon limit of the channel.
Oh no Ben...you also use Arduino, nothing can stop you now! I for one am very pleased that you use analog, digital, Integrated Circuits, and now mini-micro controllers. Solid tutorial. Thank you.
You've got a rare talent. (& forgive me for saying so but I'm someone who knows). Superb work. It's so good you could even slow down a little, make the video 50 percent longer, and people would still watch through it all. 👌❤️
oooofff! Oh God, Where was Ben all these years when I was young learning electronics and communications? Have you tried for America Got Talent Ever? .... You building up to Data and Parity Bits?
Actually, the pi already has some logic included which could handle that kind of job. :) Such like I2C, SPI and UART - those interfaces are able to take care of reading/writing, while your CPU isn't occupied by bit-banging.
But this is about bit-banging, handling it "manually" and not by all other hardware. So yes, you can use the hardware to manage all this, but you can also use C, C++ or Python (or even Scratch) to do this on a RPi with Raspberian.
I'll probably come back to it at some point, but I want to take a break and do some other stuff. The CPU covers all the basics I set out to cover when I started the project, though there will always be more I could do.
I would vote for some GPIO hardware and/or interrupt hardware. Could be just a register that stops the clock and sets the PC when a trigger is seen. I'm currently building a version of the CPU and eventually will try to include this hardware.
So the CPU is complete for now, if I understand you right? If so could you please update your website with the link to the last video "Conditional jump instructions", so it doesn't always say "more coming soon!" and everyone is thinking that the series isn't finished yet.
the quality of the content is over the roof on this channel. I really appreciate the smooth transitions, consistency of explanation, no steps are skipped, everything is explained. amazing, Ben, keep up the great work!
Creating a basis CPU wasnt good enough for him, he is creating the basis internet.
if he made a cpu and a basic web server internet in the same year (2017-2018) that is super super freaky that is literally my 2 big projects i have been doing
Samuel Miller that would be super fascinating 😍
Next up: TCP/IP, routing, How to design a web-server in 8-bit assembly, and an embedded HTTP server entirely from logic gates and transistors!
Samuel Miller funny, I also worked on some pc and OSI model simulations 2 or 3 years back. To see Ben make videos about both really brings back memories. Its basically a practical implementation of the course I followed called Computer Architecture and Networks.
That's preparation for when the government starts to control this internet.
The Bob Ross of computer engineering is back! :)
But in computer science theres no "Happy little accidents" errors might cause a disaster.
"Happy little segmentation faults"
Dude, that's exactly what I thought of as he casually laid down his first blue wire, perfectly cut to length. "And... we'll just add some happy little wires here..." Mr. Eater, the amount of planning you must do to make it look so easy is formidable!
Some nice exceptions.
MrSumkinFedor
I don't know... an out of frame switch seems like one of those 'happy accidents' to me ;)
-Jake
This guy prepares all his perfect length jumper wires in advance, I'm effin' calling it.
Great video.
ZecoRho you can get kits with various lengths, he probably picks from those
@@QualityDoggo In other videos, the wires are also perfectly prebent.
and he did all that programming with only one goof up, missing a period :-)
It's called editing ;)
The errors he makes along the way are also prepared in advance, I'm guessing. The guy is very skilled, but he also goes in depth enough so that a newbie can get into the videos, understand them, and avoid common pitfalls. Really great vids.
The thing I really appreciate about your videos is the "stream of consciousness" style where you let us see your thought process and problem solving internal voice. I learn so much more hearing you think aloud through these problems.
He is our own Tech Teddy.
Yes
It fails at Hell, it will never transmit more than 666 bits correctly..... What have you done...
Opened the Logic Gates of Hell?
DOOM!
Ben, I think you're doing a really great job teaching about some of the fundamentals. The importance of having at least a basic understanding of how all the components of a system work is often underestimated. People want to skip over it to the tasty stuff and then find troubleshooting hard. Keep up the good work!
By far the best fundamental communication protocol explanation I've watched.
I've finally begun to learn to stick to one task a bit longer (ok.. OK..a few tasks at once), but I really want to try this out myself just to see it first hand....I must not get distracted.... I must not get distracted... where did I put that other nano...crap
-Jake
??
Hello, w≡rld!
Ah, I guess RUclips doesn't do error checking either.
@GWigWam Explains the comment sections under some videos.
@@SugarBeetMC what do you mean??
how the hell did you do the three stripes!
@@--_9623 the comment section is not so grammar friendly
Isnt it crazy engineers have been doing this for like the past 50 years and we are just now blown away by it
I love how you constantly make us think we’re ahead of you, thinking “wait, that won’t work”, which is exactly what you intended of course. Great teaching, Ben.
Bit shifting finally makes sense! Thank you Ben.
I love the way he introduces a problem, calmly explains what to be expected, and how close everything is to reality (not just in an academic way). Then he presents us with a solution and an explanation on why/how it works.
These videos are really educational and informative, and he's truly a great professor!
I also finally understand bit shifting and feel mindblowww. He is the best!
Actually keeping the compiler errors in the video is probably the closest thing to reality!
Now wrap your head around this one: en.wikipedia.org/wiki/Fast_inverse_square_root#Overview_of_the_code
which part of the video did bit shifting "shift" your sense?
You are RUclips evolved. This is the first of your videos I've watched, and I'm absolutely thrilled to go back and watch the rest of your stuff. I hope to have your teaching skill one day. Thank you.
The coolest thing here to me is the way we're all sat watching this via a method which is just a few steps away from what he's demonstrating. Data in, data shoved down wire, data out. These are tests and lessons you can do in your own home, and gain a real appreciation for the fundamentals behind how this stuff works.
These videos made me realise that LED's is the electronics engineers console.log()
XD
well , what would you use if not an led light , an led screen is too complex to set up to be used for this purpose
sort of, but if electrical engineering was a language, I think it would be C++, because electrical engineering is by no means a scripting language, so LEDs are more like:
std::cout
@@maskedredstonerproz Buzzers are fun
😁
27:10: It's very clear that since ! is ASCII 33 (00100001) and " is ASCII 34 (00100010), it's just the final bit that arrived a little too soon, so the delay was almost long enough but not quite.
I've spent more time than I care to admit on RUclips over many years. This may be the best electronics/programming video I've ever seen. Truly a work of art.
31:30 A huge concept just sank in and solidified to memory at this moment. I love your videos because they break down complicated concepts into understandable steps and let the viewer follow along and make the connection naturally.
34:05 To demonstrate how much this is actually makes sense: now I'm thinking about how you would add a second data line and modify the code to alternate which one the receiver reads from at a given moment. Obviously you could increase the transmit rate, but for some reason the former seems more interesting, at least for learning.
Man, this is one of the most educational videos I've seen on RUclips
The consistency of the wiring between the tx and rx boards is extremely satisfying. My favorite sub this year.
This video is a good overview of communication.
Note: As you a measuring the crystal oscillator you are changing the circuit.
(It's a very delicate circuit, I'm amazed it even works when measured.)
Even the worst oscillators will likely not be beyond 100ppm.
To improve NRZ you can do oversampling at the receiver.
I was expecting to see some phase locking of the timers each time the NRZ state changed, or some oversampling or some other asyncronous tricks. But nope, just a clock line.
@@jnevercast It's a basics video looking at the fundamentals. There has to be some limit to the scope!
I love this guy, HE is to the point no Special video effects, no look at me " I'm on yout tube" type of videos like others do. He is to the point and knows what he is talking about and best of all he is not presumptions. Ben you are the best out there.
I’m an old hand with this stuff, but I’ve found these videos quite inspirational. I find myself tinkering much more than I used to before I discovered them. Colleagues that I’ve shared them with feel the same. Keep uo the excellent work!
15:22 That's what she said
OMG I'm DYING
Omg😂😂😂
ha ha ha. genius !!
I'm sure you've covered this before in another video but I appreciate the way you describe these topics. You allow the viewer to take the path that someone might take if they didn't have a priori knowledge of computers. It not only helps someone learn the problem but hopefully they come to appreciate how elegant some of the solutions are.
Blown away by the elegant way on which you explain this. Everything evendown to your hand gestures is so great.
Love how you break this down to such a basic level.
25:05 Everything was going great, then everything went to Hell^X@
It's actually not that hard. The extra processing required (in the loop) on the receiving can arbitrarily take too much time, whereby the receiver is getting only part of the signal, therefore the bits are a little off, and then you get jumbled characters.
@@codetutor6593 I love stuff like this. I've watched some more videos and all of this is making much more sense. I was initially making fun of the garbled characters, but i think i understand why that happens now.
@@foxroulette8016 Good for you. When you see the theory put into practice it's mind blowing. Happy creating!
@@codetutor6593 indeed! Thanks, you too!
I'm no programmer, I'm not educated enough to understand 3/4 of this video. I still deeply enjoy it and appreciate the effort 👌
15:20 "Looks like I missed a semicolon"
Me, programming in any C-like language
I learnt more in the first 10 mins of this video than I did in my whole GCSE IT.
I love how at first I was screaming at my screen that his is now how you do this... and then you fixed it, showing both common beginner mistakes and a feasible solution to it. Good balance on the detail and being engaging.
This video is a MUST WATCH for all new Elect Eng undergrads doing communication major. Save the lecturers lots of explanation. Even a you kid can understand.
Is it just me or is this guy SIMPLY AMAZING! Watching him for a while now. Loveeee his videos 😍
It's not just you. Ben has a gift of conveying knowledge in a really accessible and engaging manner. Even though I know much of the stuff he's talking about I still find his videos very interesting.
Completely agree. It's not just the content. His delivery of the subject matter makes the difference. I've been an Electronics Technician since 1974 and have seen only a VERY small number of tutorials that match the quality seen here.
I let youtube play as background while I work on projects. When your videos come on, I stop my project and watch your videos. Subscribed.
Dude, i really love your work!!
You are AMAZING...
Keep it up :)
Toncho 1 I could not have said it better.
Using strlen() in a for loop (at 3:10) wastes a lot of processing time, because for each iteration of the loop, the processor is stepping through the entire string and counts until it gets to the end. For a string whose length is constant, you can save a lot of time by saving the length in a variable, and using that in the loop.
(seen in the outer for loop in setup() in the transmitter code)
Ben Eater, this videos are insanely well made! Everything is SO clear. Perfect flow of speech and videos. The level of tidiness on your circuit layouts with straight and pre-prepared wires is unparalleled, you make electronics look as simple as assembling LEGOs, well done!
Sunday morning, turned on my computer sipping a warm coffee and saw a new video from Ben. Loved it.
I like the way how you present your videos. For example, you demonstrate the data reception error due to async transmission, and thus creating a learning moment and then coming up with a solution. Great, I'm looking forward to more videos.
I remember back in the 90's i got my first PC and a cross assembler to write code for my C-128. Since floppy disk formats were incompatible i hooked the PC parallel port up to the C128's userport. I quickly learned that i cannot do without some sort of handshake. But for some odd reason i did it the other way around. The userport's current output is to low to pull the parallel ports data pins to its level except for one (i think it was the paper sense line). I had the commodore sending the clock pulses and the PC would send a byte via parallel port to the userport.
I had a little machine code routine on the C128 watching for a ready signal from the PC and then start to send the pulses. First 2 bytes were the number of bytes to transmit.
One variety of the receiver code would also start the program right after finishing receiving it.
Good times :)
DasIllu woah that's really interesting. How old were you when you figured out to do that. Way to think outside of the box
My brain went nuts at 31 mins when you explain the clock channel, all the small electronics where I have seen the data and clock pins makes so much sense now. What a cool project and way of demonstrating data encoding.
“I missed a semicolon?”
The answer is yes. Always yes.
;
@@tdplay4135 ;
@@trubiso ;
@@someonethatlive8632 ;
Your videos helped me understand bread boards. In school, I was never tought how they work, just told where to put bits with no knowledge of the circuits or how they work
@3:18 using strlen to convert a linear algorithm into a quadratic algorithm. use `for(char * tx_byte = message; *tx_byte; tx_byte++)`.
Its not quadratic, only two times the length of the message. And the code is more readable for people not familiar with pointers
@@b4l1x the condition is re-evaluating every time, including computing the length, which is in the order of the length of the string if the compiler didn't optimise (which many do for strlen)
Ben, this is a great video. I did something similar when I taught a data communications class as a clinical/adjunct professor. Your demonstration is better than what I did.
I was looking for this thread; I spotted this issue when I watched this morning.
Ted, you are completely correct. As written, this code fragment is O(n^2) in the length of the message. However, might I suggest for pedagogical purposes (many viewers don't have our experience):
msg_len = strlen(message); /* Could be written as: for(int byte_idx = 0, msg_len = strlen(message); byte_idx .... ) */
for(int byte_idx = 0; byte_idx < msg_len; byte_idx++) {
char tx_byte = message[byte_idx];
}
Balazs Oczot, unless the compiler did the above optimization, this fragment is, indeed, O(n^2). C _guarantees_ that the conditional in a 'for' loop will be evaluated every iteration. strlen() determines the length by marching along the string searching for the null character, '\0', that marks the end of a C string. So, finding the length of the string is O(n). Because the for loop is executed n times and at each iteration the length of the string is calculated, this fragment is, as Ted stated, O(n^2). Your point regarding pedagogy is well taken.
Simon, you are absolutely correct.
I worked for a large, well known company, as an industrial mathematician doing queueing theory and performance engineering. A large project was nearly cancelled because it didn't meet performance requirements. None of the software engineers could find the problem. I never knew the exact details, but I guess perhaps 50 staff-years of work ready to be flushed down the toilet. One of my colleagues and I were given the task of finding the problem, else the project would be scrapped. It turned out that this exact problem, buried at the bottom of several nested loops, was the culprit. After fixing this, just as above, and recompiling, the project went from failing abysmally, about sixty times slower than required, to exceeding the performance requirements by about 50%. I often wonder how many projects are saved today simply by throwing more or faster silicon at it, rather than finding the root cause.
Be well & Best regards, Gottfried
@19:35, I'd write
rx_byte |= (rx_bit
"It is a very important aspect of engineering; to design systems which can deal with things going wrong or deal with imperfections."
- Ben Eater
No sh*it!! xD
Marriage.
I feel like your videos provide better info than my entire Microcontrollers class in undergrad
As a network technician with little to no knowledge regarding programming and circuits, I can figure out some of the quirks and theories surrounding the network fundamentals by seeing this material. Now I'm much more interested on studying circuits and low-level programming thanks to you! God bless!
His soothing voice coupled with his ability to break down such a complex topic makes his videos enjoyable. I have a bachelor's in computer engineering and 30 mins of Ben Eater has made me understand more about data transmission than 5years in the university. I honestly never fully understood what the point of the clock signal was before now!
"Man, I really enjoy this videos!" I say, on my third hour of watching Ben Eater videos without understanding a fucking thing in any of them
This is the correct speed and detail level for viewers interested in the subject matter and basic familiarity with electronics and programming. Presentation is excellent. Very professional.
Another 40minute video about interesting electronics? Hell yeah!
Well done. I think your patience to give a complete explanation without leaving details up to the listener is very valuable, since I assume this is for the beginner. You have to get the details at least the first time. Excellent visual recording of your presentation and the drop-in windows add a lot. Can't wait for the follow-ons.
So I just watched an almost 45 minute video full of stuff I already knew. Your videos are amazing :D
woah same, I'm just an experienced software engineer and haven't really messed much with hardware but I somehow knew where and why stuff will break :^)
same here :)
im so glad i found this channel... love understanding low level stuff, and i dont understand how there are so many programmers that go through their days writing code and not understanding these low level basics. i guess its just the way my brain works
Please do a video explaining the intricacies of CAN bus transfer, just like you showed in this video,
Your video is one of the best about basic communication. The thoroughness of your explanation is amazing.
I'd be more than happy to have you for teacher when i was taking basic comm classes.
Excellent walk-through and explanation!! Basically creating an I2C type interface. As a beginner programmer with mcu's and jumping head first into this coding/designing world (I have yet to go through the arduino tutorials), I find this type of teaching very informative and easy to follow. I learn much faster by working with "real world" applications, rather than the simulated pseudo ones that are the tutorials (hard to make the cross applications). This type of teaching helps me bridge those gaps. Much appreciated and subbed! 😁 Look forward to part 2+!
40:00 you also did that , i was also thinking about that. ' what if computer read on and off as single and any particular time when tx send 1 and then connection loosed so rx will not get same thing but 0 instead 1 so !! You covered that
This the the type of information I wish I had in High school. I learned the "fun" way...
Sr. You are the best teacher of RUclips. 44 minutes of gold. Thank you very much !!!!
Couldn’t stop watching although I already know this stuff. Great way of explaining things, building it up gradually and also showing the path from overly simple ‘non-working’ solutions to (probably) why the I2C bus is what it is.
30:00 now i know why you need a clock signal to transmit data ..... amazing. Thank you very much!
Fantastic work, Ben! Loved your explanations and the way you built it step by step. Planning to build this to show my students how physical data transmission works.
I want to say thanks to you a lot because I always watch your video when I have a sleepless until I fall asleep.
Funny thing is I need to transmit data from a bunch of Arduinos (Nano) to a single 'central' Arduino (Mega, it will most probably ask for the information so I will multiplex through the Nanos) for a school project. I was thinking about the built-in shiftOut and shiftIn functions, but they wouldn't work as I wanted to. This videos will be extremely helpful so I can get this little project done.
Using the method shown in the video is good for illustration purposes, but, you'll be much better off using SPI/I2C protocols. It's much easier to use and a lot more reliable.
Not trying to discourage you from building your own transmission protocol from scratch, it's a pretty awesome thing to do. It's just that your comment "they wouldn't work as I wanted to" made me feel like you tried using the inbuilt functionality and failed, and now think that they are not capable of proper reliable transmission. That's not the case. SPI and I2C are specifically made for communication between multiple devices. Thousands of engineers have worked on building those protocols so there is not much that they can't do in their domain of functions.
So yeah, building your own communication system is cool and good for understanding the basics, but, at the end you are much better off using the already in use protocols.
Oh, I didn't try to use the shiftIn/Out functions, I just looked the code of what they actually do and it's kind of what I want but not exactly.
My idea was to 'create' my own protocol, I don't have the idea completely structured yet, that's why I try to avoid (in a certain way) SPI (or other serial protocols). Maybe it's the idea of having complete control over what I do bit by bit? I don't know, I'll probably end up copycating it or something :d
Just use the UART - you can combine multiple serial data sources into one with a simple AND gate. So long as only one ever transmits at a time, you will need a protocol to avoid or handle collisions.
For multinode networks, use CAN !
Use I2C if you need to communicate with multiple Arduinos with the least among of wires required, since the serial protocol is build into it. Define the addresses of the slave Arduinos, and use your master Arduino as the main one to communicate with them.
This is sort of the best ever explanation of digital communication I ever have heard. It was and still is my daily bread, but one thing is using it, one thing is to explain it. Very well done!
At @22:50 , line strncat(), when you're sending infinite zeros in the demo right after, wouldn't you be overwriting the message char string passed it's allocated 16 chars? So pushing zeros beyond the end of message?
In C, strings are null-terminated, so writing a null at the end of the message just "overwrites" the null that was there anyway and doesn't make the string any longer. But it would definitely be a problem if it kept receiving more data (beyond 16 characters). So you're right that if we were doing anything serious, we ought to check for that.
I found you for about a year ago and i love every little thing you'r making, and i can't wait to see more from you.
Much love from Denmark :D
25:04
Looks like a classic case of the Satanic possession bug. I'd recommend a code exorcist but I imagine Ben will purge the spirits by the end of the video.
Apparently all he had to do was interrupt their thinking process.
Thanks for the video. Your method of teaching micro electronics is the best I have seen so far. The way you play dumb by letting errors happen and then fix them is such a teaching style which can only be done by a genius.
Me: writes a "hello world" program
Ben: hold my beer
Perfectly cut and bent jumper wires*
You write "Hello World"... while Ben builds an HTTP server out of logic gates. xD
I like the tricks you're using to hide some of the complexity that could distract from what you're trying to teach here, such as:
- using strncpy to copy 1 byte, which conveniently interprets a 0 as an empty string
- setting update_lcd = false immediately after checking it, to minimize the effect of the TOCTOU race condition (and then updating the whole LCD on each loop iteration so that if you trigger the race, so it still doesn't end up corrupting the display)
Hey Ben, Did you know that scope you have can be unlocked to twice the sample rate and have some other additional features through an online key generator? It was a pleasant surprise when I found out mine could do way more when it unlocked all the features.
Wait so to get the hardware you already own to work fully you need a key?
I always like the way you explain underlying concept through examples and problem scenarios.
Nice way of explaining effect of unsynchronized clocks on data transmission.
I greatly appreciate your process, your talking through all the points, and the detail that you go into. It’s awesome. Thank you!
i like the way you present information. I've opinion of what extra info might be presented: you started (8:40) with framing bit which is start bit in UART (or maybe link to that video) but you ended with clock which is closer to USART... also i think it was nice to remove the delay in transmitter (although i think it will not affect because delay in LCD library is big already) so maybe print after recieving everything.. and its nice to briefly talk about why the wires are twisted ;).
Have you tried simply setting the bps high enough to start seeing 'natural' errors? It seemed kind of odd that you mentioned it but didn't test it considering how easy it ought to be.
With the clock, this design will be error free up to rates well above the speed of an Arduino. That is, if I removed the delays altogether, you'd just see the correct message appear "instantly" (at least to the eye) on the other side. The "natural" errors I mentioned start to show up in wireless communication (where there's more interference) and at very high bitrates (multiple millions or billions of bits per second).
Ben Eater Makes sense, excited for the next video!
You could also introduce errors by adding noise to the transmission line. This could be done by a white noise generator and a restive adder circuit. By adding noise and messing with different coding schemes, you can attempt to get close to the Shannon limit of the channel.
I ran into errors at around 2KB/s with a raspberry pi
I usually don't subscribe to a channel having watched only 1 video, but I'll definitely do so now.
25:17 Ben shows us how to receive messages from the realm of the demons.
Hell dwdaw90adwjjawoidojiaewoiewe
Love the naive approach to solving the problem. Stumbling to the answer. Very easy for anyone to follow along.
"so let's slow it down a bit"
Oooh... i see what you did there ;)
Oh no Ben...you also use Arduino, nothing can stop you now! I for one am very pleased that you use analog, digital, Integrated Circuits, and now mini-micro controllers. Solid tutorial. Thank you.
Hello, your presentation was REALLY, Really, really good 😉 "Thank You", thank you very much; I am going to try this with an Arduino Uno 😎
You've got a rare talent. (& forgive me for saying so but I'm someone who knows).
Superb work. It's so good you could even slow down a little, make the video 50 percent longer, and people would still watch through it all.
👌❤️
oooofff! Oh God, Where was Ben all these years when I was young learning electronics and communications? Have you tried for America Got Talent Ever?
.... You building up to Data and Parity Bits?
This video is a great way of saying that hardware communication interfaces are a miracle. UART, I2C, SPI, CAN bus, etc...
try how TI sends data in between calculators.
Excellent work! You have answered many questions I've had. No I2c, no extra hardware. You just know your stuff!!
Hey everyone, Ben is back!
This taught me more than 2 years of IT lessons on my high school. But that says more about you than about my school, great video!
This is gonna be perfect to try out with my Arduinos, thx :D
Makes me love the UARTs and their HW bit-banging all the more !
You are awesome! You are inventing internet and computers again!
Patryk 2005
They definitely need reinventing, certainly at present they are an amalgamation of patches and add-ons to stuff that is donkeys' years old
This October your channel will celebrate ten years :D Thank you for teaching us such cool stuff!
Looks nice, is that possible for Raspbery Pi to Raspbery Pi , with Python and via GPIO Pins ? :-)
Absolutely
I was also thinking along same approach
Filler Bloch fwiw, raspberry pi already has a built in serial interface.
Actually, the pi already has some logic included which could handle that kind of job. :)
Such like I2C, SPI and UART - those interfaces are able to take care of reading/writing, while your CPU isn't occupied by bit-banging.
But this is about bit-banging, handling it "manually" and not by all other hardware.
So yes, you can use the hardware to manage all this, but you can also use C, C++ or Python (or even Scratch) to do this on a RPi with Raspberian.
I understand absolutely nothing of anything he ever says. And yet, I watch his whole videos and have subscribed...
Don't judge me...
Wait are you done with the entire cpu project?
I'll probably come back to it at some point, but I want to take a break and do some other stuff. The CPU covers all the basics I set out to cover when I started the project, though there will always be more I could do.
I would vote for some GPIO hardware and/or interrupt hardware. Could be just a register that stops the clock and sets the PC when a trigger is seen. I'm currently building a version of the CPU and eventually will try to include this hardware.
Build two computer that talk each other? :)
So the CPU is complete for now, if I understand you right? If so could you please update your website with the link to the last video "Conditional jump instructions", so it doesn't always say "more coming soon!" and everyone is thinking that the series isn't finished yet.
in my cs modul we also had clocked latches and stuff and you are the first that actually gave a reason what we need the clock for
I'd love a hardware implementation of your Manchester encoding video, great work.
Just XOR the clock and data!
I just watched all 43mins of low-level data transmission....for fun. Thank you Ben Eater!