How a Character LCD works Part 1

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In this episode I take a look at Character LCD screens and how to control them.

[@SlantsDraws]

You misunderstand your audience if you think we'll find this boring. I'm loving this insight into technology!

[@Raymix]

Yup, love the vids and mature, smart audience, rare around this site.

[@bill_the_duck]

If anything, I was disappointed he didn't take the LCD apart and explain how it actually works, not just how to interface with it.

[@verdatum]

I think he's a little gun-shy about trying new stuff after that one video on AI got such a negative response. That must have been rough to experience; but that's the risk when you push into new territory.

[@wartoc3708]

One of the great ways to demystify electronics and learning is taking them down to their root. It makes transitioning to more complex electronics easier, troubleshooting, and adapting knowledge from seemingly different fields.

[@limera1nx]

Me too

[@unicodepepper]

I may not talk for everybody, but I personally love watching low-level technical videos like this

[@amdhd6990]

Emily Nightfire I usually have no idea what's he doing or talking about but yeah I love it anyway

[@masterszene]

Samuel Fabiny 8-Bit Human Spaghetti :)

[@davidkellerfreeman]

i love these kind of video too

[@masterszene]

David Keller Freeman Human Videos 😊

[@williamcorcoran8842]

Also, a key part of this video: Most students of technology are perfectionists. This video teaches the students to work around mistakes and not just hit reset and start of over.

[@walktroughman1952]

I think universities create that kind of insecurity, due to inconsistent ranking of projects depending on the instructor

[@KimboKG14]

me: funny channel naming joke! :D *the 8-bit guy: literally programming with 8bit*

[@monad_tcp]

(it would be funny if chinese people used a 4bit mcu to make the LCD instead of VLI digital logic, someone must have decapped those things)

[@lemau8458]

k

[@lennonmclean]

true, but all the computers he deals with (commodore machines, atari 2600, apple II, etc) are all 8bit as well

[@lennonmclean]

8bit means that the width of the registers on the cpu and the bus are 8 bits wide

[@Flamekebab]

Literally one of the first times I've understood what a capacitor is for. Thanks!

[@sasabarisic8864]

It is not exclusively for this kind of stuff, it has many many uses in analog electronics too.

[@Flamekebab]

I know, but the many, many other uses have never been explained to me in a way I can appreciate. I still don't quite understand what the point of resistors is, for example. They add resistance. Great. Why? How does that help achieve something? Etc.. In this case I can totally see the point of a capacitor and that makes me really happy!

[@sasabarisic8864]

Well the point of resistors is to resist the flow of electricity and convert a part of the electrical energy into heat. If you, for example, powered a LED without a resistor it would burn out because the power source can deliver too much power and LEDs burn out. Therefore you connect a resistor to waste the rest of the power the LED can't consume.

[@sasabarisic8864]

i.imgur.com/IERGyO6.png The resistor in the video is called a pull-down resistor. When the switch is turned on (B in my image), the electricity will go trough the path with least resistance (some of it still goes trough the resistor but that can be ignored, it depends on the value of the resistor) therefore the gray wire has ~5V potential - logical 1. If you turn the switch off, the gray wire will be connected to 0V trough the resistor, therefore it will have ~0V potential - logical 0. If there was no resistor, the wire would be floating and effectively acting like an antenna, because the circuits in the LCD are very sensitive they will act on it. The resistor also has to have a reasonably high value so the voltage drop across the resistor is high enough. If it's low, it will effectively act like a short circuit. Look up ohm's law.

[@AngeloGi]

How many first times have there been?

[@DavidMarsden]

I bet you aren't expecting this comment... This is one of your best videos. This is a great project to get kids started. I really want to do it myself. Can't wait for the next.

[@seriouschicken6333]

Completely agree. One of you best videos.

[@Manawyrm]

Definitly agree! Highly interesting and makes me want to fiddle with some HD44780 LCDs.

[@kaliachiarezza]

I agree, I think I'd like to attempt something like this. I am 16, so that just proves your point. I think I have an old LCD somewhere, but I'll have to buy switches most likely.

[@RealLuckless]

I've already linked this video to a number of computer science and engineering professionals with ties to education. It is an awesome project even for university level stuff I think, and kind of wish the digital systems courses I took had used devices like these as steps between the blackboard diagram theory and going to things like FPGA chips on a breadboard. I'll probably also build this with my nephews here soon when they get out of school for the summer.

[@tomkrawec]

I bet you aren't expecting this ellipsis... Actually, no, I bet you were. Sorry. But I agree -- this is a damn fine video! Also I like the music.

[@maxwell_edison]

Thanks for explaining Bouncing! I am a programmer and I never knew why they called it "Debounce" even in code that had no physical parts inputting. It originates from this I understand now.

[@slaughterround643]

check out Ben Eater's 8-bit computer

[@maxwell_edison]

I regret this username more and more each coming day.

[@bhawtesh8644]

This can also be seen in computer mouses as they use the physical switch‽

[@vittosphonecollection4134]

that's a *B* ouncing problem!

[@froschgrosch5247]

@@bhawtesh8644 i think there are debounced switches (but only to a certain level) so most likely there also is software debouncing

[@darkmojojojo]

Soldering header pins is the way to go with those LCD screens.

[@Wes8761]

It pained me when we he soldered to pin header. Its honestly worthwhile to just solder pin headers or SIP sockets to everything like that and use dupont connectors or generic jumpers to connect to it and just use non permanent or semi permanent connections. If its the final thing I'll ever use the device in I still always leave some way to remove it just in case. Good design practice. Cheers!

[@darkmojojojo]

@@Wes8761 yeah that was cringe inducing.

[@kyle-hb3pz]

I think mixing in technical videos is a great idea. This channel is already interesting with the history of the devices, but seeing some of the technical aspects would be interesting too. That could just be my opinion as a computer science major though. Thanks for the awesome content!

[@cluckyx443]

Thirded. Absolutely fascinating.

[@Talasas]

Also agree.

[@xyzshantaram]

Fifthed. I love this kind of stuff, and I actually thought the AI video was cool too. It was the layman's guide to A.I. creation.

[@MrPedros1989]

Kyle Mayer I agree as well. Im beginning to learn Arduino and finally now I understand how those screens work

[@kyle-hb3pz]

Kamil Szpytma Arduino is a great platform to play around with. I suggest finding some libraries to make dealing with these screens a bit easier. Good luck learning and happy tinkering!

[@onedeadsaint]

I am ready to be edutained!

[@pakzoo7243]

hacker

[@gold4963]

Same

[@alfonsot.9439]

Probably a Patron that paid early access to the video when it was unlisted

[@reirei_tk]

A cromulent edutainment embiggens the souls!

[@onedeadsaint]

correct!

[@subliminalcastillo2126]

How can anybody dislike this video? This video is so enticing, educational, and wholesome and also has great music. This man literally created what most of us would use breadboards or circuit boards for- all on a hard plastic box. Some people just seriously suck & want to watch the world burn.

[@TheTopMiners]

Everything about you is a 90's time capsule! The way you dress, the way you speak, how your videos are recorded, the catalogs you have and of course all the thech you use in the videos! I really apreciate that, keep doing awesome and informative content! Thank you!

[@RobertLiesenfeld]

I liked this video, great for someone getting started in hobby electronics. I especially appreciate that you show your mistakes! Too many people edit their videos down to make it look like they got it perfect on the first try and leave the budding hobbyist with the impression that they, the newbie, are just hopeless at it. Everyone makes mistakes and you often have to build it twice to get it just right. Looking forward to part 2!

[@Seff2]

Robert Liesenfeld moreover, its good to see how he works arround the mistakes he has done. that can be really helpful.

[@artstrutzenberg7197]

Yup....and the one "fix" (flip the labels around).....whole lot easier than having to rewire things :D

[@Hyxtryx]

@@artstrutzenberg7197 I think he should have rewired it and not told us, because... I hate to say it, but that was a very rookie mistake. With toggle switches like those, when you flip them "down", it connects the center pin with the "top" pin, not the "bottom" one. It's a common mistake because it's counterintuitive, but a facepalm for anyone who's used toggle switches before. Rewiring would have been as simple as swapping the + and - wires going to the switches. The 8 data switches would have needed only 1 wire swap. (unless he tied off of them for something else).

[@thomasmarshall4472]

I made almost exactly the same comment. It's perfect to show how you can fix and replace. I made a toy car with my 11 y.o. son out of printer parts, (gears, transport mechanism, etc., and a motor), and it took 3 1/2 hours because of all the things we had to fix and re-do along the way. IF it had taken 15 minutes and slapped together, it would have been a fail IMO, because we wouldn't be doing the engineering fault-isolation techniques. "Hmmm......how do I solve this?"

[@stewiegriffin6503]

well done. it's not too deep, it's just right.

[@JackBealeGuitar]

King Parodije that's what she said (sigh)

[@stewiegriffin6503]

lol

[@NotSoGoodGamer18]

MultiTarded 😂😂😂

[@shabbarvejlani]

Multiple concepts touched here: 1. Character LCD pin description and how the communication protocol works. 2. SPDT switch and how to punch in digital 1/0 using it. 3. How to connect a pot and generate analog voltage input using it 4. Floating connection issue resolution using pull down resistor 5. Switch denounce issue in push button and fixing it using RC circuit. Over and above, how to debug and proceed ahead when you come across a problem. Thanks for this series. Feeling angry on KZbin algo for taking 4 years to show this on beautiful channel.

[@technixbul]

Just change the +5V and GND wires on switches and all will be fine

[@technixbul]

@tgmforum tgmforum they are upside down now ... i mean main power wires that going to the switches ... just 2 wires, not all 24 (10 in this case) the data is on middle pins and wont be touched. This will exchange low and high levol on switches

[@rowanthorley6616]

OMG lol

[@mrburns366]

Yes.. just swapping two wires.. Not sure why that didn't occur to 8-bit guy. Sometime very smart people miss the forest for the trees ;)

[@TheOriginalEviltech]

@@technixbul Тролнаха те братле :D

[@Bandicoot803]

@technixbul: Thought of exactly the same thing as they're common-railed.

[@kingcarcas1349]

8 bit guy can use power tools, Linus woulda lost a finger

[@chrisfratz]

We're talking about the same guy that grabbed a power tool without knowing that it plugged in. So yeah he probably would have lost a finger.

[@TheLegoman332]

And then drop it

[@GRBtutorials]

8-bit-guy can use a soldering iron without problems, Mehdi from ElectroBOOM would burn himself to get some laughs out of the public.

[@loganiushere]

kingcarcas1349 I love both of these channels, so that joke really hits home for me.

[@zombieslayer1468]

@@TheLegoman332 LOL

[@fredrikjonsson1503]

I liked it, more episodes like this.

[@ZagnutBar]

Fun LCD story For decades, the company Medtronic Minimed manufactured insulin pumps with LCDs well after they stopped being manufactured commercially. How did they accomplish this? They bought the LCD manufacturing equipment. They did this for years rather than modernize their insulin pump designs. The modern Medtronic insulin pumps now have modern color touch screens, but they didn't start implementing them until 2014(!) So if you need some LCD screen manufacturing equipment, call Medtronic Minimed. Maybe they can cut you a deal :)

[@adityaagarwal636]

Literary loved the way you accepted you mistakes, and told each and every detail so easily, that many can't explain in days🙏☺️

[@realtuber6522]

Those LCD with the damaged pads can be fixed by scratching the traces next to the damaged pads and soldering thin wires directly to the traces.

[@demagmusic]

I was thinking the same thing. I've saved many dead things with this technique

[@theRealLANman]

Yeah, I've done the same. 1st, I would take a razor & scrap off the protective film. I remember using a desoldering strip as a wire. It'll bind to the board, then attach a wire on the other end.

[@robertorigami9295]

Sounds interesting Realtuber thanks for the tip it's​ a cool ghetto style technical repair technique 😄

[@nos1000100]

Ive patched together broken PCBs doing that same method

[@nos1000100]

@@dcfuksurmom well in my case. The PCB and traces were rather large. It was for some gauges for my Datsun 280zx. I was fixing the dash and the connector for the gauges was tight and broke then I tried to unplug it. When I finally got the gauges out, I was able to scratch the coating on the traces and patch them. I also put some double sided tape to hold everything down. Really isn't as hard as it may seam

[@clyde34]

Fun fact: High for READ and low for WRITE is a standard that spans all electronics handling, registers - basically everything. And it is easy to remember: I/O looks like 1/0 Read - Input - I - 1 - High Write - Output - O - 0 - Low

[@mechaform]

How did I miss this set of videos? I could’ve sworn I’ve binge watched all of your content. Boring? Not at all.

[@adityashukla7849]

To be honest, I perfectly know how LCDs work but that green LCD in the thumbnail looked so beautiful, I thought to give the video a like for that.

[@NicolasTsagarides]

Instead of rotating the switches, why don't you swap the gnd with the vcc wire that you soldered on those rails?

[@roelskiunplugged1134]

That's exactly what I was screaming to the screen, but he didn't hear me :)

[@TommyOlsen]

Yeah, same here!

[@ThePiGuy24]

Exactly!!

[@GHA476]

Nicolas Tsagarides wouldn't that cause an issue with the way he wired the enter switch?

[@tomlomax9909]

This. Easy enough to swap around the enable key too.

[@hexial]

This wasn't boring at all! Good level of technical detail :)

[@primanox007]

This video just makes me smile :) I love the music, the attention to detail, and just building cool little things! You are a joy to watch, sir!

[@RomanKuechler]

Hello David Your videos are really great! The calm and above all clear pronunciation makes it very easy, even for foreign speakers, to really understand everything. And you can see how much effort you put into production. Thank you!

[@BertGrink]

Too technical? heck no, i love it! :D

[@ZeeZeeBun]

These things... work a lot more simply than I expected..

[@raggededge82]

Computer engineering is not difficult, it's just complex :)

[@louistournas120]

This LCD screen is like a computer. I thought it was going to be just a LCD screen.

[@hekkn]

@@louistournas120 same

[@TheChrisey]

@@raggededge82 Complexity is what makes things difficult for people.

[@TheChrisey]

It's because it's a lot more sophisticated at handling itself. That screen assembly has its own builtin microcontroller

[@NeoLudditeDave]

I love the way you cover the problems you encountered & what you did to resolve. Much more realistic than a 'perfect' build.

[@bunnybunnyloaf]

It was really interesting seeing the mistakes get made and corrected. Makes me feel better about times I wrote a program with a syntax error.

[@ArjunRaviFunniestManOnEarth]

Ronald Deese hey it happens

[@theale8821]

Whenever he flips the on/off switches I get a feeling of extreme satisfaction

[@lordofthecats6397]

He should re-name it to "The most satisfying video in the world (Trust me we got it this time)"

[@dwen1816]

Please do more technical-themed episodes like this one because it was great and incredibly interesting.

[@dmlavign]

Great video, just thought I'd mention you could have switched the Red and Black lines feeding the 8 data switches and that would make them work as desired. Thanks for the cool content!

[@kuchenzwiebel7147]

This video should be an example how explanatory videos should be. I knew nothing about how the data to a LCD is transmitted and I got it instantly when watching this video. Keep it up!

[@forthwithtx5852]

Never would have learned this if I was just surfing KZbin. I'm also a scavenger of just about everything I get ready to toss in the trash. Saved my butt many times.

[@black_squall]

But not a hoarder right? ;)

[@NickMoore]

That's an awesome little project! I had no idea they were that easy to drive.

[@olivierorsola]

I agree. So nice.

[@jkobain]

Well, they are. It's because the displays mentioned in this video contain quite nice driver IC and they in China used to copy (as far as I recognize) its behavior, so whenever you need to replace your 8*1 LCD and use 1602 or 2004 all you need to change in your project is to make the symbols fit nicely on your new screen, all the rest driving things remain the same.

[@douglasmacleod7791]

Nick Moore qqqqq

[@douglasmacleod7791]

Olivier Orsola a

[@resrussia]

I really enjoyed this video. Your explanation of how character LCDs work is clearest one I have encountered. Keep up the good work!

[@fauxpasiii]

More like this, please. I'm a beginner, and watching this video at 8:28 was the moment I finally grokked what a pull-down resistor is. The debounce fix was also a great learning opportunity, very glad you leave in all the initial bugs and show how you fixed them and why. Thank you!

[@darksquirel]

as an avid viewer and someone who understands analog electronics I'd love to see more build and in depth videos like this

[@TheOsnovis]

No no no, it's perfect. Explain everything the way you like it and take as long as you like, we love your videos!!

[@spacekitt.n]

yes please i like the long vids

[@Iceflkn]

Totally awesome project! Love that you ran into problems since we got to see your solutions. Well done!

[@airborne501]

I have been working as a software engineer for over 20 years and I alway wanted to learn more of the electronics side of things. You have to be the best instructor I have see. I have learned a lot from you. Thank you so much.

[@RiverNaiad]

Thanks for your videos. I always watch them with my dad. He's a big Amiga guy. Can't believe how much you like Commodore. He thinks your restoration vids are the best.

[@jamesevans1601]

Awesome project, this really demystified an 8-bit display. Well done!

[@walterheukels]

Very cool. I never realised how smart these things are, they're like little terminals!

[@carlojav2]

I referred to this video today to fix an issue I was having interfacing a 4x20 LCD with a Microchip PIC16 and it helped me to discover the problem. Excellent explanation, please keep making videos like this one, the 8-bit microcontroller programmers like me will appreciate it 😊👍.

[@TheLeonardProduction]

This is excellent! I've always been very curious about how data is sent to a board or electronic piece, this is really cool! Do more videos like this, not a lot of people do videos about this stuff for "the masses", usually they are for engineer students, and are way more complicated and less entertaining than this

[@MarcellDAvis1103]

Leonard Productions i really want to see a series

[@peterjansen4826]

All kind of Arduino projects would be nice but it is not realy within the scope of his channel I guess.

[@imgoingtobuygoogle]

Agreed, would love to see a how to series on circuitry!

[@00sey35]

Leonard Productions a

[@CattoRayTube]

This was great! It's like the Ben Heck Show but far more accessible for complete beginners haha.

[@TheRedCap]

It really is! I have this place near me called Skycraft, and they're like radioshack, but 1/3 of their prices. I bought a screen, as well as a few other components and put this project together.

[@tonifasth]

Really good content. Highly detailed instructions without any extra fuzz. Great job.

[@DunderChief918]

This is probably my favorite 8-bit guy video! Ive always wanted to know how those screens worked, but thought it was too difficult to learn.

[@shenron02]

great video, you should have used an old school embossing label maker, it would give it more of an 80's look :)

[@nachobidness6667]

The NES Renegade yes! Dymo labeler FTW!

[@shenron02]

the doc from bttf always used them :)

[@tompov227]

loved this it makes me wanna be an electrical engineer and I hate electrical engineering

[@tompov227]

Lol same about the electrocution thing

[@transistortester]

There is no risk of electrocution with low voltages (it is taught that up to ~30 volts is completely safe, although the actual threshold is higher), and working with higher voltages is reasonably safe as long as you don't do anything really stupid.

[@redrik009]

EE here. Just be mindful of current and paths that current can take. If you're attentive to this, you'll be fine. I've never electrocuted myself or come close to it.

[@redrik009]

Also, if you're worried about working with the mains in your house, electricians handle that, not engineers. Engineers design things.

[@CalcProgrammer1]

Be a computer engineer, it deals with digital electronics and software without a lot of the analog/high voltage side of EE. I went into embedded software engineering with my CompE degree, though I enjoy all things electrical and electronic as a hobby anyways.

[@samaelturcios_1986]

My respect for you, nice video and very educational. I am and electronic technician (and future engineer) and it's my first time i see how a screen lcd really works in manual mode.

[@idj20]

I continue to be immersed in your videos as I catch up on your KZbin channel! I normally just skip/jump forward in videos, but in here I just want to watch them carefully from beginning to end. Keep 'em coming in!

[@Koisheep]

Thanks to this video I finally got what are capacitors and transistors.

[@Crlarl]

There were no transistors shown.

[@bennylofgren3208]

Carl Siemens "No transistors were harmed making this video." (However, a couple of innocent LCD's got 3rd degree burns...)

[@C2H5OHist]

Technically there are a few thousand transistors in that lcd driver ic though. But a very educational video nevertheless!

[@varungb]

Sir, you are genius, creative and imaginative. One the best videos on KZbin.🙏

[@arelenas]

Great and very useful video. There are a few channels about electronics that I follow that go into tiny little details (like eevblog). I really love them but I find your videos refreshing and very easy to listen no matter how much you go into details and whatever the subject is in question. I always get that creative spark “hm, I can do it now. Let’s roll!”, and I really do it.

[@no_handle_required]

This is excellent. Watching how computing actually works behind the scenes of a gui or a keyboard. Total awesome.

[@spugintrntl]

This was a lot of fun to watch! I'm actually trying to get into building small electronics so for me personally, this kind of technical video is great.

[@spugintrntl]

...Not that your other stuff isn't awesome too.

[@jonathaningersoll6213]

This is the type of content I love to watch; keep up the great work!

[@jperih]

This was DEFINITELY fun to watch! You could always have a separate channel for the too-technical things, because this does fit into that category.

[@stevedoubleu99B]

You have no idea how helpful that was. I have been building stuff for a long time, but never really understood these devices and t he way they operate. I will build this unit and start playing immediately. Thank you!!

[@lesdmark]

The display on the printer shown at the beginning at 0:31 is a VFD also know as a Vacuum Florescent Display. It's an honest mistake a lot of people make though. Still love the video!

[@joshodom9046]

I knew it wasn't lcd, but I didn't know what it was

[@lesdmark]

Yep, Fixed now. Thanks!

[@newagederpderp]

The VFD is effectively the same as a CLCD.

[@skyem5250]

There are VFDs that run on similar driver chips to character LCDs. Same interface and function, but different display technology.

[@newagederpderp]

@oH well,lord! i have no idea its a two year old comment and i can't be assed to google it

[@PastPinball]

+The 8-Bit Guy, Thanks for this video! It is exactly what I needed! I like that you went "deep" on it. It left me with no questions and an urge to start working on stuff. I look forward to the second follow-up video.

[@StevieRekt]

I have several of these LCDs that I have harvested from printers and other devices that were bound for e-waste. This video has shown me a great way to start using them in projects! Thank you!

[@alexgochenour8740]

This was such a well thought-out video. Thanks! Not too technical at all, please keep them coming!

[@lilsponge8034]

I'm only 15 and I wasn't even born in the 80 and I'm interested in this channel with all the retro items . Keep up the good work

[@bagelmaster8]

I'm 16, I love this too, especially how he did this without a computer, it makes it way more simple

[@xyzshantaram]

14, me too. I'm fascinated with some of the stuff they used to do to make things work. Ingenuity is dead in this era.

[@TheBrokenLife]

You guys all have a golden opportunity to start messing with this old stuff now while it's dirt cheap. I hate to sound like the old guy (but by comparison I very much am), but that's what I did back when I was a kid, but mechanics are my interest. I'm a mechanical engineer now, but I still cut my yard with the same tractor I was messing with when I was 12 and it's still older than I am.

[@bagelmaster8]

+Siddharth Singh +Siddharth Singh yeah it's crazy to learn how computers evolved from simple vacuum tube logic gates to what we have now. I think most of the ingenuity today is in the software as opposed to hardware

[@lilsponge8034]

Siddharth Singh Siddharth Singh I'm glad he bringing old items like the first answering machine and how to use the Commodore 64 work

[@stuartmcconnachie]

Surely just switch the 0v and +5v on the bus bars to the switches?

[@cyanlite7231]

Stuart McConnachie They have their own controller and font gallery.

[@GewelReal]

+Cinhi Young switched the mechanical ones

[@AsilarWindsailor]

i absolutely enjoyed this video on Character LCDs and I am beginning to tinker around with electronics myself. This video is very helpful for learning little things like bounce and I believe this is the FIRST time I've seen an explanation on how the potentiometer is to be wired. Never dawned on me that it's used as a variable voltage divider. I just never thought of it like that so it makes perfect sense now. I think we all would like to see more videos like this!

[@wolfrobots118]

That video was not boring at all....I LOVE when you make videos like that. I always learn from you. Something about the way you explain things is really satisfying. I am going to watch part two after I write this. With your content I always watch every minute.

[@CSBlackShadow]

Awesome and informative content as usual. And as others have said, most of us don't find it to technical or boring. You can explain things very well so its easy to understand. Keep up the good work!

[@Datan0de]

I really enjoy your channel, and this is probably my favorite video yet. Don't worry about it being longer than most of your vids - the content is well worth it. Seeing the process and the missteps adds a lot to the educational value and helps us noobs not feel so bad when we make mistakes! One question: by wiring the capacitor between +5v and the LCD, doesn't that bypass the switch and make a short?

[@igotes]

Capacitors don't conduct current. They can be "filled up" and "emptied", but once full, no current will flow until the voltage difference between the two pins changes. In this case, when the button is pressed it will discharge. Hope that made sense!?

[@southjerseysound7340]

I agree,this has to be my fav episode yet and I hope for more like it and longer

[@Datan0de]

It does, at least conceptually. Thanks. I'm going to have to breadboard up some circuits and play with this more.

[@Birgenshire]

At steady state (once the capacitor is fully charged), capacitors are modeled as open at low frequencies (including DC), and a short at high frequencies (exact frequency depends on the capacitance). This property is what makes them a key in basic frequency filters too. You are correct though for a brief moment when first applying the voltage it is a short but small capacitors like this charge very fast!

[@PY4ROE]

I've never seen such a well-explained video on lcd! My congratulations for the explanation and the spectacular didactics !! a big hug !! I like all your videos on the channel !! Tiago, Brazil.

[@GoatOfTheWoods]

Please do more like these! I actually never knew how these work, and it was fascinating to understand. And the presentation is opposite of boring, you'd make for a good teacher.

[@codedragon6237]

You're someone who teaches how to make stuff without microcontrollers (indirectly perhaps), that is really impressive

[@thomasleonard5260]

Your switches aren't upside down, they're just European - the convention here is down position for on !

[@grahaminatorca85]

Thomas Leonard That's so weird and backwards, lol

[@gamefoun]

Thomas Leonard whoah, I didn't even realise switches here were like that, I checked some and it really is like that

[@brendanwalker8903]

Thomas Leonard wait, in the u.k., we have up is off and down is on. is this not the case in the usa?

[@mikemoos]

Yeah, it's cheaper to buy foreign, and just mount it sideways :D

[@mumblic]

I was thinking the same, down is the "on" position (EU). Had now clue that in the US it was different. What about the rest of the world.

[@pdubowner]

This very quickly became one of my favorite channels. I've been watching non stop for like 30 hours.

[@therobot1080]

Slep skedule off

[@Despondencymusic]

I thoroughly enjoyed the deep technical aspects of this video.

[@ITVOIP]

This was great. I always wanted to use one of these a project. You made this super easy. thanks for keeping in the mistakes/problems.

[@peter-william]

I love your videos! could you do a video on how emulators work?

[@peter-william]

or on the ti83 calculator

[@gold4963]

Retro emulators. Like NES and SNES. But emulators are a recent invention. And legality is questionable...

[@Sebastian-xy3xk]

GOLD 1515 Emulators are legal, they just seem shady because of millions of people use them illegaly by downloading ROMs (Because no one wants to make backups of their own games sadly ;-; )

[@TheBrokenLife]

Emulators, even NES and SNES emulators, aren't recent at all. I think the first NES emulators are around 25 years old. I've had a NES an Genesis emulator for my Dreamcast for almost 20 years.

[@UltimaOmegaZero]

@GOLD 1515 No, emulation has been a thing since at least the nineties.

[@vincenthiggins6091]

Do not underestimate your audience. very informative with the work that you do. and unless you do not have enough storage space on your SD card one video is never too long.

[@Victooriux]

awesome work man!! I´m seeing all your videos now that I moved from professional musician to IT dev and digital electronics and I think your content it´s awesome.

[@richardlincoln886]

Re switches upside down Can you just flip the +5/GND leaders onto your switch busses?

[@CattoRayTube]

I was wondering the same thing, but David probably has a reason for not doing so. Commenting so I can see any reply!

[@BinyaminTsadikBenMalka]

Yeap, you can!! He must have overlooked that solution.

[@anotheruser9876]

And re-solder/switch the leads powering the LCD

[@BinyaminTsadikBenMalka]

not required, if you saw the electronics on the back of the switches it's a very simple thing to swap the polarity on them.

[@Shananium]

I was just wondering were there a good way to test witch way your switcher are before soldering them.

[@ryanr3291]

Love your more technical and educational videos most!! Make more of them!

[@timyorkokc]

I really love your channel! I learn something every time I watch one of the videos. I'm working on a project now that will require an LCD screen. Now that I've seen this video I don't feel intimidated. Thanks very much!

[@halonothing1]

This series has taught me everything I needed to get started with character LCDs. This was one of the first circuits I remember making when I got into electronics a couple of years ago and now I'm havgin a blast revisiting it. I've been learning assembly for the 8051 miicrocontroller and one project I'm working on now is to interface it with a character LCD and control the LCD wth the 8051 and not knowing how to use noe makes it a lot harder to do. =P

[@nievasdario]

This was amazing. Now I want to get one of those displays and start playing around! Thank you!

[@BloggerSWF]

The very first time i see someone expaing LCD display with so simple way! I am your fan, i ove your videos, you must bring more technical contents fo us! Cheers from Brazil!

[@raven4k998]

the enable pin is an enabler you know

[@danieldare2640]

This is the greatest video I’ve seen in a long time thank you, awesome and I wouldn’t worry it’s just the right amount of technical knowledge and not boring at all

[@OttosTheName]

Not boring at all, a bit nerdy, but I love it! I think you have a great balance between educational and entertaining. I spend a lot of time messing with Arduino's, Raspberry Pi's, programming, electronics, but I sometimes feel like I rarely know what's réally going on behind the screens and these kind of video's are super useful.

[@DavidCourtney]

I loved this video and would love to see more like it. I enjoy your normal stuff, but delving into electronics projects like this is far more interesting to me. Do a YT search for "Ben Eater 8-bit computer". That is my current hobby/passion that I'm working on.

[@AlexanderKrivacsSchrder]

Yes! Ben Eater's videos are amazing! I wait around in anticipation for his next videos; they can't come soon enough!

[@kylesulcebarger8399]

David - you two need to team up on an Orbiter controller!

[@krokofan4425]

oh i am so waiting with you! i actually just bought all the stuff you need for the computer and will start building it soon.. still curious how the control logic unit will work out!

[@DavidCourtney]

Yeah ... these last few videos have been super exciting. (Well, they all are!) But seeing everything starting to tie together has literally put a smile on my face. I started working on it 3 weeks ago today. I've been following the build in the same order as his videos, so I first built and tested the CLOCK module. Here is a picture of what it looked like it when it was done. drive.google.com/open?id=0B-6ynjm4RtfudXRZLUhNek4ycFU Though I've since gone back in and changed the wires to have a uniform color. When I first built it, I was just using U Jumper wire. And I didn't have 0.01uF capacitors on hand when I first completed it, but I've since gone back and added all the various smoothing capacitors that he talks about. Then I built REGISTER A. I accidentally swapped 2 wires coming out of the 74LS245, but I found the mistake quickly. I tried to keep my wiring as neat as possible, so it took me a while to build that first REGISTER. Then I went on to build REGISTER B. I didn't make any mistakes on that one. Next was the INSTRUCTION REGISTER. Since that one is mirrored, and since he doesn't show the build in his videos, I had to make sure I didn't mix any of the connections up. Once I had all 3 REGISTERS done, I spent quite a bit of time testing them. The way the enable and load signals work wasn't entirely clear to me, and I definitely got a bit confused, but once I figured it out, it was pretty easy. After the REGISTERS were done, I started on the ALU. That was A LOT more difficult than anything up to that point. The number of connections that have to be made, and all the routing of wire is really difficult. When I was done, my ALU acted like it had a bunch of problems. The output didn't make any sense. I ended up mapping out all the connections "on paper" so I could wrap my head around it better. Then I went through each connection by putting my multimeter in continuity mode, and I checked everything from point A to point B. It turned out that I had like 4 wires misplaced. I'm not sure how that happened, but I suppose it wasn't that surprising. On the ALU, you end up with wires on top of wires on top of wires. It's very difficult to make it look neat. Here's a picture of what my REGISTERS and ALU look like. drive.google.com/open?id=0B-6ynjm4RtfuUDZray1tYTR4UG8 I built REGISTER A with a different brand of wire than everything else. So the shades of blue and green are a lot darker. Eventually I'll go back and rewire that REGISTER so everything is uniform in color. So after the ALU, I started building the RAM module. And that's where I'm at now. One of the 74LS189's I got from Jameco was DOA, so that caused quite a bit of a delay. But now I'm up to the very last set of steps for the memory module (RAM module build - part 3) where I need to connect the 8 data inputs. It's been a fascinating process to do this myself. Sometimes frustrating, lol, but always fun!

[@omikronweapon]

For someone like me, with a decent brain but zero knowledge of the hardware yet, i found the level of "depth" quite nice. The pins always seemed like magic numbers. Knowing what they do and how is very informative. I had heard of "capacitors" but hearing and seeing a practical use makes it seem easy to tackle. Seeing even the basic construction of the box and power supply gives the entire project the feeling of "this is EASY! I can definitely do this now!". I liked the pro-tip of stripping old wires too.

[@trumpetsounds2341]

OmikronWeapon fyi if ur still interested and dont know: capacitors store charge. the capacitance value of a capacitor in farads is equal to the ratio of charge able to be stored per volt across the capacitor

[@monad_tcp]

pins are magic numbers, just like argument order in a function is magic. (or you read the docs)

[@neonsigns6721]

I stumbled across this video, I have seen many of your videos and enjoy them. But I wanted to tell you that this one is awesome. I have been using these hd44780 displays for years in different projects and programing using different types of language from assembly up, and i just wanted to tell you it was really cool to see this done by hand. So thank you

[@joeschmo5171]

I love these deep dives into these types of projects! Please keep them up!

[@Skelpolu]

Waiting for a super geeky 6502 controlled LCD setup

[@Skelpolu]

please make it happen

[@dalekmun2010]

Something something look up the OSI 300. Something tells me he'll get to that sooner or later (We've come a long way from iBook reviews, keep in mind)

[@brocktechnology]

You just spent 14 minutes on a detailed exploration of the hitachi HD44780 display interface and you never said HD44780. I think that's pretty funny. Great stuff, looking forward to part two.

[@38911bytefree]

New OLED and LCDs from brand like Winstar wont even tell that is a 44780 controller ... while it is obvious that they work in that way. Probably the model is not too relevant. For the ones that want to go in DEEP, it is worth mentioning. The 44780 is the FIRST datasheet I had read long ago. Its a good excersice, but not that clear and since if the complet spec, a bit bulky.

[@The8BitGuy]

It was in the original script but I took it out. I mean, pretty much any character LCD you buy these days is based on the HD44780. So I didn't feel there was any reason to go into it.

[@brocktechnology]

8-bit guy I would say that is an entirely fair observation however Google operates in the tradition of Rumpelstiltskin, if you want more information you must know its name.

[@rspict]

Awesome video. Don't be afraid to go "too deep" into the project and be technical. This is a technical channel, this is what we want, and who doesn't like shouldn't study electronics at all ! Thanks for sharing :)

[@sio2tube]

I've just discovered your channel and I'm loving it, I'm watching dozens of videos a day.... You're doing a great job. Greetings from Italy