The best part about your videos is that you explain the entire the creative process, including the troubleshooting part. Things NEVER go to plan, and that's always part of the fun.
Ditto. Kudos to the 8-Bit Guy for showing his actual process and not an idealized or perfect process that certainly could have been obtained by simply showing (via editing or making several attempts) only steps that were successful. What we’re seeing is an honest, real-world experience.
I was struggling with use old Noritake VFD 16x2 display with Raspberry Pi and spend a lot of hours trying to figure out what's going on. It worked for about a few minutes and then started showing "random" characters each time. I thought, that it is because my VFD is not 100% compatible with HD44780 controller, which is common used in LCD displays like in this video. But the reason was the cables between RPi and VFD, and the USB power cable. They did not contact correctly. But it was strange, because I didn't touch them and it was happening! Thanks to this video I didn't give up! I love this guy :)
When using 4-bit transfer mode, it is recommended to use pulldown resistors on vacant data lines, else they may accumulate static and cause initialization glitches during LCD power-up. Additionally, hooking things up directly to parallel or serial ports without current limiting resistors, PTC fuses or diodes for protection is very risky. I've fried my share of hardware that way. This is especially critical when you expect to be hot swapping homebrew peripherals. When things are plugged/unplugged the electricity sometimes may flow in unexpected directions. Not all computers or microcontrollers know how to limit current or deal with reversed polarity. A loose ground wire is a recipe for disaster also. I had one brush against the logic pins of a serial port for a split second and that was enough to destroy the RS232 chip. Good thing you caught it.
Doubt it since this is a channel that has actuall information and it's fun too watch. People like drama, scandals and other bullshit, I won't say nudity, because who doesn't like tities?
This video series has everything I like, combined! (c64s, chiptunes, soldering irons, lcd screens, coding, cool t-shirts, schematics, multimeters, and even music keyboards hanging in the background). Everything a real man needs. Dave you made my day!
Sorry about your luck on the power supply failing. Do you know about shift registers? They are useful when you're limited on pins and I think you could use one or two of those to also drive multiple LCDs.
When it comes to character LCD's there is plenty of interface options - parallel, serial, 8/4 bit, and my personal favorite - SPI. I was making a "Back To The Future" console and was able to drive all digits with a single Atmega328 chip without any additional multiplexers. Unfortunately I failed to realize my LED displays were rated for 3.3v instead of 5v so at some point the setup burned out. Lesson learned.
My favorite thing about this video is how you walk through the entire process, sharing some valuable best-practices and debugging tips along the way. Many thanks for the video!
@@choccymalk123 All 3 of my c64 PSU's put out ±6v under load now, and two of them are the late spec beige bricks that came with 64c's. The circuitry in them is basically unchanged and they are potted all the way through unlike early spec "boot" bricks which leaves the caps and diodes out of the resin, that's why they die, the 7805 regulator is not cooled properly. Here in Europe there were some models of PSUs that didn't get potted and can be serviced but they are fairly hard to come by.
I never thought I could feel such intense suspense for old technology. When I was young I wondered how LCD screens worked but of course this video wasn't available then and I wasn't guided in the right direction. Thank you so much for satisfying that childhood wonder within me.
Seems like what's needed is the old "Crow-bar" device, a thyristor wired across the supply big enough to short it out linked to an over-voltage detector. It's crude and it isn't nice to the power supply but it saves the computer.
I probably didn't explain: I'm not talking about an add on. The circuit would have been buried inside an old PSU anyway and the aim was to either pop a fuse or put the supply into current limit in the event of regulation failure. Damage to the PSU wasn't an issue as long as it prevented the overvoltage hitting the 5v rail.
Ew, no. Crowbars were A Thing in electrical engineering back in the day. If the PSU is sending too much voltage, _it is already damaged_. It should be obvious that having the PSU commit suicide without killing the electronics is preferable to having the PSU commit suicide and taking the electronics with it.
What I like the most about this channel is that your projects suffer the same perils we, simple mortals, suffer I mean, if you check other channels, manuals, tutorials, etc, the projects just work the first time for them, no hiccups nor glitches, and I think you learn the most from mistakes and how to avoid/fix them, so it is really appreciated that you explain how to debug the problem as it is time well spended. Thank you very much, also the music is so great!
It's not mine. He played my latest song in the middle (Falling in love with you), but the first and last song is CLCOLLAB's song. You'll find them on SoundCloud, first title on their profile. :)
"The 8-Bit Guy" -- You have the gift for teaching. Good video, good audio, easy to follow narrative telling a story. Thank you. The following is not exactly on point but...Re: Commodore power adapter high Voltage -- If you are powered by NIPSCO here in NW Indiana, one becomes accustomed to supply irregularities. Over about a 9 month time, I went through 3 older but previously very reliable HP and 2 new Samsung laser printers with all looking like something was really glitchy with the power supplies. The Samsung would power up and sit for about 10 minutes looking like it was downloading revised BIOS and then starting working normally. Then a washing machine with a capacitive touch screen bugged out but I was able to control using wire wrap in a pinch, and microwave bugged out for a short while, but came back to function normally. Submersible pump, compact fluorescent lamps also bugged out over a period of a few months. That summer was exceptionally hot and I wondered whether the neighborhood, which is about 60 years old, had the required service lines. So I checked the duplex socket Voltage... 143 V. Months later, NIPSCO replaced a line transformer serving three houses including my own. Subsequent line potential- 121 V. A neighbor later told me of similar problems but did not know of the high line Voltage. NIPSCO never told us of any problems. In 2020, my house had 18 power interruptions and only one was likely due to weather. NIPSCO suggested I install a whole house UPS.
- I really dig the "How It's Made" type background music. - "Little program" my rear end! LOL! - Most importantly, though, I *really* like seeing the process of encountering, diagnosing and addressing failure. I'm very, very timid when it comes to working with electronics and seeing you encounter failure states actually encourages me. "If it breaks on me, I'm not stupid...and I can fix it." Or to put it another way -- I think one of the most important subtexts of your videos is "It's okay if it fails."
That was the first thing I was taught when I started mending PDP-11 computers in 1981, "Check the voltages." We sometimes had 3 PSUs on one computer, one for the processor, one for the memory and one for the 1Mb memory expansion.
you are my favorite youtuber. I love how you include all "errors" showing in the end that sometimes hardware just fails on you - and that you persist and dont give up until you succeed. its very inspiring . cant wait until next video comes out, your notification are the best ones ^_^
Your videos are always enlightening and informative. Watching someone problem solve is so much more informative than just watching someone do something that works flawlessly.
I'm studying computer engineering, and we are using a NDS to learn how to control the Input/Output changing manually the registers, using And/or functions, and a bunch of hex numbers. For people like me, who loves that kind of stuff, it's awesome to understand how PCs work. Thanks for your work doing this videos :)
Rip C64. So many memories. It had a life in the spotlight, showing off hardware and software. And now it is reached its untimely death. You will be missed. R I P Commodore64 1982-2017
These technical episodes are brilliant. I've always seen projects where people hook stuff up to parallel ports and stuff like that but they never explain the nitty gritty of what's going on. Personally I'd love to see more videos at this sort of level. It's technical without going overboard, and with your diagrams and descriptions, it's hard to not understand what's happening. Really brilliant work.
Wonderful episode. I grew up with the C64 being mostly interested in software while my father was a hardware / electronics geek. Now, as a grown up software developer, looking back to what I have missed is wonderful, getting to understand how things actually worked and the stuff my father was always trying to teach me when I was a kid. Best channel ever.
+Mr T. Guru The problem with doing that is, those old black bricks are *solid epoxy* around a PCB. I took one apart once to try to do exactly what you're proposing. Drilling out the epoxy without damaging the PCB is a lot of hard work.
SpearM3064 Actually, if you heat the epoxy to its glassification point (typically in the vicinity of 120-160C based upon past projects) you can easily chip away at the epoxy and just scrape it away. It is still a bit of work and you have to be careful, but it is much easier and with much less risk of damaging the board or components as you do not need to be nearly as aggressive.
kazoon Most Zener diodes will not reliably handle that much fault current well and also have a rather high impedance versus what one would want to see for prompt and reliable overvoltage protection. A much better choice would be a either TVS diode or a crowbar circuit utilizing a Zener and SCR to short the power supply and blow the fuse. However, the power supply must be capable of delivering enough current to blow the fuse (not always a given) quickly or you may burn up the TVS diode or SCR if the short can not be cleared by the fuse (though, if your SCR has sufficient heatsinking and is rated for the necessary current then it can endure, but most crowbar circuits expect the fuse to clear the fault quickly and are undersized for a sustained short.
I did something similar using FreeBASIC on Windows XP. No idea if FreeBASIC is still around but it gave easy access to the parallel port on a modern OS.
This video really shows the issues with trying to do something cool with technology. Nothing works the first time, and then you break the things you're working with, and then there's a few hours trying to troubleshoot the issue only to show that you need to start over with a new piece. I love it because it's so damn realistic.
Hey 8-Bit Guy, thanks for your videos, they enlighten my evenings :D By the way, do you plan on repairing your, now dead, Commodore64? If so, could you film the process and upload it? I do like videos of this style, like "searching for the problem, finding it, changing the parts, maybe soldering"
It's nice to know that other people experience projects going south spectacularly like this. Happens to almost everything I decide to try, and I usually give up long before getting to any kind of resolution. So this video was immensely satisfying to watch. Also, one minor correction that I hope you will accept in the spirit it is intended (pedantry is not always a bad thing!): 42 is not the meaning of life, the universe and everything. 42 is the answer to the ultimate question of life, the universe, and everything. The question of course remains a mystery. A small but important difference.
it is a text screen, not a graphical one. So there are large blank fringes around letters - like a "######" pattern that cannot be lit at all because the pixels are not there on the LCD. Furthermore, it would require constantly reprogramming character generator on-the-fly - possible in theory but slow and hackish. It would require connecting a graphical LCD with a completely different interface.
Love the exercises in trouble shooting. I had many hours of fun using the old ZX-81 and then Sinclair 1000 writing programs that included machine code, building a parallel port that allowed me to make a garden monitor using home brew analog to digital converters and wet and dry bulb thermistors to measure soil humidity to alert when water was needed. Every robotics class could benefit from these basic instructions and trouble shooting methods. Bravo!
Using a BASIC program to control the screen makes it slow enough that you can ignore an important requirement of the HD44780 controller chip in the LCD module. That requirement is that you give it enough time to respond to a command before sending the next one. Using toggle switches and a push button gives it plenty of time and, it seems, the BASIC program is slow enough too. But if you write code in assembly language you need to bear in mind that most instructions need at least 37us to execute, and some take as long as 1520us. You can use delays or you can poll the status register of the chip to determine when it's no longer busy before sending the next instruction. Maybe this is covered in part 3. I haven't watched it yet.
Great video! Love seeing the problems, troubleshooting and solutions. As a equipment maintenance tech in a semiconductor production facility, we deal with these problems on old technology every day! Keep up the great work Dave, love the videos!
Sure.. and with some shift registers I could add even more. But the point was I could add up to 3 without any additional hardware. Maybe I should have mentioned that.
+8-Bit Guy you can also write a C program to control the parallel port of a PC, it is not that hard. Maybe you can make another episode of controlling an LCD with a PC?
Its pretty possible to talk directly with ports under linux. I don't know the situation in windows tough. In fact I've written a program for it. I can post it if I find it.
It is still a loooot harder than just typing it in Basic. That was one of the things i stubmbled upon when testing audio-output for Arduino (atmega328), rasperberry Pi (ARMv6) and Saprtan FPGA (3E 250). arduino was the easiest, spartan you had to do a bit more, and raspberry is a mess in comparison.
8V on a 5V chip is usually a death sentence for most. Even if chips do survive, it's the question... which ones did? I have arcade boards and once I was diagnosing why one of my boards was having artfacts and random issues, turns out PSU died and sent 7 volts out to the 5V line... That made me sweat but thankfully I caught it in time and seemed to have saved it. Also had one where it inexplicably caught fire when I powered on. Thankfully that was only a tantalum cap that blew. All of these things leave fear of the formidable power switch and always makes you qustion "Am I sure this is correct" before flicking the switch lol.
Naaaaaa they can be repaired ... issue is BLACK SCREEN could be EVERYTHING in the machine, it the worst scenario for a repair with no info unless you poke some measurements. It a comprehensive machine, schematics are not that easy to read, but for someone who knows about electronics ... it will survive.
You seem to know a bit about it about it. Have you repaired one before? I'm currently working on fixing my C64 but it's a guessing game as to what exactly is wrong. Yes, I have the black screen. I bought a new PLA chip as internet adviced. Made sure I get 5V, check. Still black. Any tips?
Well, I have repaired 3 C64 and read the schematics. Blank screen is the most common sympthon, since machine cant start. I repaired only ONE black screen. I bet hard on PLA, VIC II and ROMS. I have another C64 and the ICs were socketed. All of them tested fine (I was shocked). In this machine was a latch register, like 74245 or similar. The C64 has many glue logic chips around. If you dont have a donor to test, I would first try with a cart. Some of them start fine since the C64 doesnt need to look for ROMS (yes, ROMS go BAD as well). I would take the 6581 out from the system. It not required to start and can take the bus down. When I was child I got black screen and the C64 was found a BAD ROM CHIP. The colprits are the chips that are more stressed, VIC, PLA, and ROMS. Those run hot. One time I got BLACK screen due to a bad connection on the VIC II. The VIC was socketed. And the chip is a toaster. It ended ruining it own socket because the self heating and consuption. But the VIC was fine. Just the 40 DIP socket need to be replaced. It was MELTED on 2 pins. So, take the VIC out and have a look around. The VIC is usually inside a rectangular CAN with a coper finger on the top. RAM, MPU and CIAS ... are less prone to damage There is a color RAM there. Another thing is the RESET, C64 uses a reset (not sure if made on a 555) chip. This needs to come ok. Easy test: connect the 1541 or 1571 (if you have one) I believe that when the machine is powered on, the reset signal is sent to the 1541 as well. So you will notice it (not enterely sure by now ... to be honest).
I mean this in the nicest possible way, it's really nice to see your mistakes, failures and eventual success. I feel like most RUclipsrs wouldn't be so open to doing so.
I really appreciate these videos. I don't understand the subject matter well enough to go out and buy some components and then build stuff, but I understand enough to get the context of the technology. It's cool to see where computing has been and the potential for where we're going. 8 Bit Guy makes it accessible. :)
I love how clearly you are able to communicate these concepts. I know a lot of the stuff you go through, but i feel like i know it better and feel smarter after watching your videos each time. :)
its from Hitchhikers Guide to the Galaxy. people built an oracle machine that could answer any question. so they asked it the answer to life, the universe, and everything, and then waited around for like 200 years for it to compute the answer. and the answer it gave was 42. at which point they realized that they would need to ask it what the question was to life, the universe, and everything, in order for the answer to make any sense.
Great video! I never really did anything interesting with the user port on my C64 back in the day so it's cool to finally learn about how it works. I really like how you're not afraid to go into all the setbacks and failed attempts you have in your projects - way better to show how these things go in practice rather than trying to make it look easier than it is!
will we see a future build of a voltage "watch dog" to go in line with the C64 power supply. Shouldn't be too hard to get a blinking red LED and cut off.
I really like the fact that it wasn't all edited to "hide" the power supply problem, or reshot... made for a really interesting "real life" video on the topic!
This was more tense and thrilling than literally any sports game I've ever watched. It was like a high-tech murder mystery. And it was all the power supply with the high voltage rail in the studio. So many different plots all going on at once, all of the plot twists. Will the screen work? Will the second one work? A third? Another computer? 10 10 would watch again.
This takes me back. I used the 8 bits on this port on my c64 and made a pcb that held 8 optoisolators. I connected the switch sides of the optoisolators to the front pcb of a Fisher VCR to increment and decrement the channels and "press" record and tape speed. I lived in Japan on a military base and some local channels had American shows in English if you had a similcast box so I would switch this on or off. We also had one base channel that has just begun showing Star Trek the Next Generation a whole season behind the US. I wrote a program that was a great improvement over the regular VCR programming. I can't believe I was able to figure this out with c64 books back then and no internet. :-)
I'm so grateful your putting out these videos. Beautifully presented and I'm learning stuff that I've wondered about for many years. Keep up the great work!
There's a known issue with the C64 power supplies that means that when they go bad, they send too much voltage down the line and fry... I want to say it's the memory, but I'm not 100% sure. I've never run into it myself, but I came across stories about it when I was just looking into getting a less gigantic power brick for my 64.
but the simple fact that the nand gates saw 8+V can mean they probably died. FETs are extremely fragile to voltage. Simply rubbing your feet on the carpet and touching the pins of a device can kill it.
Cartman - you do realize that ESD is on an entirely different scale and irrelevant when it comes to constant "low" overvoltages? Cause ESD can easily be more than a couple thousand volts - that can arc over and directly destroy the junction.
Well I'm hooked.... :D Looking at your videos bring back a lot of sweet memories of my own projects and exploration of the VIC-20/C-64 back in the 80's. My VIC-20 was a bench mule for lot's of funny projects and it did it's final service as a printer server for my BBS in the early 90's :D I do have a broken down C-64 with a 1541 in the attic, so I'm tempeted to have a go at fixing that!
really nice video, just recently learned about interfacing an 8051 microcontroller to an lcd at college amd these made things much more clear and intresting
I'm sure it's fine, they have an internal regulator for this purpose. Besides, they're very robust little machines, they'll survive just about anything.
Aio-inc: Nope. going form 5V to 12 v is a bad bad bad thing. cause yes, you do build some protection into those things, but they are designed to handle 5 v and maybe slight overvoltages. but at 12v even your zener diode will just burn up.
Brick provides two voltages. One is AC and the other is 5V DC regulated. The AC is the one that is rectified and regulated to 12V since VIC uses BOTH 5 and 12V (c64 and 9V on the 64C), cassette is 6V, but it feed from 12V. I believe that SID also uses both. The 5V come from the brick. The reason they have sent AC to the C64 is to provide grid clock (50Hz or 60Hz) to the SID and CIAs. But yes, even when it seems like too much, bet only a couple of thing got damaged, and the rest if fine. I have seen 3.3 micros operated CORRECTLY on near 8V ... MOS ICs (not the brand, but the type) are "more flexible" than TTL. C64 is basically made of MOS chips, but there are some TTL parts as well.
Just de Analog part of it. The digital part runs on 5V, otherwise it will blow everything in the bus. Same is true for VIC II. They are "mixed" signal chips.
![Eminem - Fuel (feat. JID) [Official Lyric Video]](http://i.ytimg.com/vi/t5H_CewqpKA/mqdefault.jpg)
I think I'm addicted to this channel.
+brusspup What are you doing here?
Wait, brusspup also watches The 8-bit Guy?
YOU'RE ALIVE!!!
Yep. Me too
Same
The best part about your videos is that you explain the entire the creative process, including the troubleshooting part. Things NEVER go to plan, and that's always part of the fun.
I agree!!!
Ditto. Kudos to the 8-Bit Guy for showing his actual process and not an idealized or perfect process that certainly could have been obtained by simply showing (via editing or making several attempts) only steps that were successful. What we’re seeing is an honest, real-world experience.
7:45 ye just not good stuff
I was struggling with use old Noritake VFD 16x2 display with Raspberry Pi and spend a lot of hours trying to figure out what's going on. It worked for about a few minutes and then started showing "random" characters each time. I thought, that it is because my VFD is not 100% compatible with HD44780 controller, which is common used in LCD displays like in this video. But the reason was the cables between RPi and VFD, and the USB power cable. They did not contact correctly. But it was strange, because I didn't touch them and it was happening! Thanks to this video I didn't give up! I love this guy :)
Death toll: 2 LCDs, 1 speech synthesizer card, 1 C64, and 1 C64 power supply. Rest in peace.
yeah... It was like a murder-suicide, huh?
This video also shows how flaky the Original C64 PSUs are. They have killed one too many C64s.
Electronic suicide!
We should play them a Cannon Fodder Recruit Theme.
Collateral damage.
This was quite interesting. Now we need a repair the C64 video!
indeed... and something about the power supplies.
@@The8BitGuy hey man where did you get that shirt please?
@@The8BitGuy Yea we really do... R.I.P The 8-Bit Guy's C64 ????-2017
@@The8BitGuy don't suppose there's been a repair video for the c64? Or was it beyond recovery?
@@alexmcd378 I hope it wasn't beyond recovery.
When using 4-bit transfer mode, it is recommended to use pulldown resistors on vacant data lines, else they may accumulate static and cause initialization glitches during LCD power-up.
Additionally, hooking things up directly to parallel or serial ports without current limiting resistors, PTC fuses or diodes for protection is very risky. I've fried my share of hardware that way. This is especially critical when you expect to be hot swapping homebrew peripherals. When things are plugged/unplugged the electricity sometimes may flow in unexpected directions. Not all computers or microcontrollers know how to limit current or deal with reversed polarity.
A loose ground wire is a recipe for disaster also. I had one brush against the logic pins of a serial port for a split second and that was enough to destroy the RS232 chip. Good thing you caught it.
I've never seen a better explanation of how these screens work. The toggle switch demo did it for me. Thanks a bunch.
billybbob18! Change your name to Osciman!!!!!!!!!
Why? Its his name
This video is a great demonstration of Murphy's Law, and methodical troubleshooting.
THAT POWER SUPPLY FRIED A PERFECTLY GOOD C64!
KLLL IT WITH FIRE
KLLL?
KLLLLLLLLLL
@@lejohn2682 DID HE STUTTER .
Like the self destruct mechanism. Fully!
PLANNED OBSOLESENCE
This is one of the best channels on RUclips! I'm calling it: you're hitting a million subs by the end of the year
AgentK 04 extremely unlikely look at social blade
Yeah!
Doubt it since this is a channel that has actuall information and it's fun too watch. People like drama, scandals and other bullshit, I won't say nudity, because who doesn't like tities?
Sure hope he does... one of the few RUclipsrs that really, really deserves it. The amount of work for each episode is amazing!
+Infinite loop not just that, but he's such a cool, laid-back fellow as well, i always enjoy his videos.
This dude looked so chill even when he completely fried his C64
what we dont see is his shooting to the PSU off-camera :p
At time of writing, your comment has 64 likes
@@alerey4363 I'd be furious at myself if I were him. He knew better than to use the old power supply.
Pretty sure we didnt see him trashing half his studio, taking a bottle of xanax, and then resuming shooting the next day. :)
I was really surprised that he used and old power supply too.
Will we see a C64 repair video?
most likely...
I hoping not. ;)
I'm looking forward to a C64 repair video! I have a 'black screen' C64 myself.
Yes, please. I really wish to see this machine restored.
Full length feature, hopefully.
This video series has everything I like, combined! (c64s, chiptunes, soldering irons, lcd screens, coding, cool t-shirts, schematics, multimeters, and even music keyboards hanging in the background). Everything a real man needs. Dave you made my day!
A real man says no to an electric soldering challenge.
great episode! I appreciate that you include your failures and troubleshooting into the episode. This makes the episodes even more interesting.
Shame about the PSU. I only work woth old PC parts, but I always use modern power supplies for this very reason.
Sorry about your luck on the power supply failing. Do you know about shift registers? They are useful when you're limited on pins and I think you could use one or two of those to also drive multiple LCDs.
Indeed.. You could use it to feed in the data lines in a serial fashion.. then use the enable line separately.
The 8-Bit Guy I (or my family) have a Casio CT-87
deltaray3 how do you used this item
or you could use the 3 pins for a Demux and use up to 7 screens.
When it comes to character LCD's there is plenty of interface options - parallel, serial, 8/4 bit, and my personal favorite - SPI. I was making a "Back To The Future" console and was able to drive all digits with a single Atmega328 chip without any additional multiplexers. Unfortunately I failed to realize my LED displays were rated for 3.3v instead of 5v so at some point the setup burned out. Lesson learned.
My favorite thing about this video is how you walk through the entire process, sharing some valuable best-practices and debugging tips along the way. Many thanks for the video!
I am sorry for your C64... I hope that the damage isn't too severe..
Now I am going to check my PSU.
Your PSU should be fine, if it is newer.
@@choccymalk123 All 3 of my c64 PSU's put out ±6v under load now, and two of them are the late spec beige bricks that came with 64c's.
The circuitry in them is basically unchanged and they are potted all the way through unlike early spec "boot" bricks which leaves the caps and diodes out of the resin, that's why they die, the 7805 regulator is not cooled properly.
Here in Europe there were some models of PSUs that didn't get potted and can be serviced but they are fairly hard to come by.
I never thought I could feel such intense suspense for old technology. When I was young I wondered how LCD screens worked but of course this video wasn't available then and I wasn't guided in the right direction. Thank you so much for satisfying that childhood wonder within me.
Always use an over voltage protection device when using an original C64 power supply! I recommend the "SaV64" (Google it).
Seems like what's needed is the old "Crow-bar" device, a thyristor wired across the supply big enough to short it out linked to an over-voltage detector. It's crude and it isn't nice to the power supply but it saves the computer.
I probably didn't explain: I'm not talking about an add on. The circuit would have been buried inside an old PSU anyway and the aim was to either pop a fuse or put the supply into current limit in the event of regulation failure. Damage to the PSU wasn't an issue as long as it prevented the overvoltage hitting the 5v rail.
There are tons of overvoltage protection circuits on the web. You can easily implement them with a transistor, a zener and a couple of resistances.
Ew, no. Crowbars were A Thing in electrical engineering back in the day. If the PSU is sending too much voltage, _it is already damaged_. It should be obvious that having the PSU commit suicide without killing the electronics is preferable to having the PSU commit suicide and taking the electronics with it.
What I like the most about this channel is that your projects suffer the same perils we, simple mortals, suffer
I mean, if you check other channels, manuals, tutorials, etc, the projects just work the first time for them, no hiccups nor glitches, and I think you learn the most from mistakes and how to avoid/fix them, so it is really appreciated that you explain how to debug the problem as it is time well spended.
Thank you very much, also the music is so great!
I really enjoyed the tense synth tune, reminds me of Kavinsky or Perturbator.
This is a good reminder for all of us to spare the remaining machines by not using the original power supply with them.
Hehe, The Adventures of 8-Bit Guy continues! Most amusing and informative, keep up the good work. :D
Anders Enger Jensen you are a great person
Anders Enger Jensen it is going little bit to the style of videos from Druaga1
is it your song at the end? If so love it and 8-bit guy's great videos!
It's not mine. He played my latest song in the middle (Falling in love with you), but the first and last song is CLCOLLAB's song. You'll find them on SoundCloud, first title on their profile. :)
Anders Enger Jensen I love you!!!
I remember Commodore 64's through grades 1 to 3. 1990 to 1993. It's amazing they are still around!
They dang are still around. Nostalgic nerds such as me and 8-bit guy likes to go back to nostalgic things.
Great Video! Unfortunately your C64 died :(. Just a question: When is Part 3 coming?
Tristan Kundrat Now
ruclips.net/video/pQk3XgpuaJ4/видео.html
"The 8-Bit Guy" -- You have the gift for teaching. Good video, good audio, easy to follow narrative telling a story. Thank you.
The following is not exactly on point but...Re: Commodore power adapter high Voltage -- If you are powered by NIPSCO here in NW Indiana, one becomes accustomed to supply irregularities. Over about a 9 month time, I went through 3 older but previously very reliable HP and 2 new Samsung laser printers with all looking like something was really glitchy with the power supplies. The Samsung would power up and sit for about 10 minutes looking like it was downloading revised BIOS and then starting working normally. Then a washing machine with a capacitive touch screen bugged out but I was able to control using wire wrap in a pinch, and microwave bugged out for a short while, but came back to function normally. Submersible pump, compact fluorescent lamps also bugged out over a period of a few months. That summer was exceptionally hot and I wondered whether the neighborhood, which is about 60 years old, had the required service lines. So I checked the duplex socket Voltage... 143 V. Months later, NIPSCO replaced a line transformer serving three houses including my own. Subsequent line potential- 121 V. A neighbor later told me of similar problems but did not know of the high line Voltage. NIPSCO never told us of any problems. In 2020, my house had 18 power interruptions and only one was likely due to weather. NIPSCO suggested I install a whole house UPS.
The only channel that is more entertaining than majority of my subscriptions. :D
- I really dig the "How It's Made" type background music.
- "Little program" my rear end! LOL!
- Most importantly, though, I *really* like seeing the process of encountering, diagnosing and addressing failure. I'm very, very timid when it comes to working with electronics and seeing you encounter failure states actually encourages me. "If it breaks on me, I'm not stupid...and I can fix it." Or to put it another way -- I think one of the most important subtexts of your videos is "It's okay if it fails."
Am I the only one who gets giddy when one of these comes out
AuthenticAlex me too!
i love them too, and am now considering digging out my old commodore 64 from the storage room and tinkering around with it again
Totally!
Kristian Svalland how do you activate this item
No. I got a semi when I saw the alert, am fully erect watching it now.
That was the first thing I was taught when I started mending PDP-11 computers in 1981, "Check the voltages." We sometimes had 3 PSUs on one computer, one for the processor, one for the memory and one for the 1Mb memory expansion.
you are my favorite youtuber. I love how you include all "errors" showing in the end that sometimes hardware just fails on you - and that you persist and dont give up until you succeed.
its very inspiring . cant wait until next video comes out, your notification are the best ones ^_^
Your videos are always enlightening and informative. Watching someone problem solve is so much more informative than just watching someone do something that works flawlessly.
I'm studying computer engineering, and we are using a NDS to learn how to control the Input/Output changing manually the registers, using And/or functions, and a bunch of hex numbers.
For people like me, who loves that kind of stuff, it's awesome to understand how PCs work.
Thanks for your work doing this videos :)
Have a good time and stay safe of any bad power supplies!
What I like about this channel is that also failures and problems are explained. This is very instructive.
Rip C64. So many memories. It had a life in the spotlight, showing off hardware and software. And now it is reached its untimely death. You will be missed.
R I P Commodore64
1982-2017
it's admirable that you leave your troubleshooting phase in your uploaded work. gives a realistic view of the challenges involved.
we want part 4: repairing c64
What the deuce?
Not sure as the voltage could have fried all the chips in a microsecond
These technical episodes are brilliant.
I've always seen projects where people hook stuff up to parallel ports and stuff like that but they never explain the nitty gritty of what's going on.
Personally I'd love to see more videos at this sort of level. It's technical without going overboard, and with your diagrams and descriptions, it's hard to not understand what's happening.
Really brilliant work.
4-bit guy
😂
64bit guy 😂
@@RowynOfficial 15bit guy >.>
single bit.....!
Savage
Wonderful episode. I grew up with the C64 being mostly interested in software while my father was a hardware / electronics geek. Now, as a grown up software developer, looking back to what I have missed is wonderful, getting to understand how things actually worked and the stuff my father was always trying to teach me when I was a kid. Best channel ever.
Rip C64 1982 - 2017
You can put a diode on the motherboard to prevent that :-/
I know but it acts like a fuse and it's better than nothing :-)
+Mr T. Guru
The problem with doing that is, those old black bricks are *solid epoxy* around a PCB. I took one apart once to try to do exactly what you're proposing. Drilling out the epoxy without damaging the PCB is a lot of hard work.
SpearM3064 Actually, if you heat the epoxy to its glassification point (typically in the vicinity of 120-160C based upon past projects) you can easily chip away at the epoxy and just scrape it away. It is still a bit of work and you have to be careful, but it is much easier and with much less risk of damaging the board or components as you do not need to be nearly as aggressive.
kazoon Most Zener diodes will not reliably handle that much fault current well and also have a rather high impedance versus what one would want to see for prompt and reliable overvoltage protection. A much better choice would be a either TVS diode or a crowbar circuit utilizing a Zener and SCR to short the power supply and blow the fuse. However, the power supply must be capable of delivering enough current to blow the fuse (not always a given) quickly or you may burn up the TVS diode or SCR if the short can not be cleared by the fuse (though, if your SCR has sufficient heatsinking and is rated for the necessary current then it can endure, but most crowbar circuits expect the fuse to clear the fault quickly and are undersized for a sustained short.
Dave, nothing ever goes as planned. I love that your videos show this, as opposed to a flawless finished product.
I did something similar using FreeBASIC on Windows XP. No idea if FreeBASIC is still around but it gave easy access to the parallel port on a modern OS.
"Windows XP"
"Modern"
Wat
Electronics Idiot FB is still alive and kicking!
@@randomcatdude Modern compared to the C64
This video really shows the issues with trying to do something cool with technology. Nothing works the first time, and then you break the things you're working with, and then there's a few hours trying to troubleshoot the issue only to show that you need to start over with a new piece.
I love it because it's so damn realistic.
Hey 8-Bit Guy, thanks for your videos, they enlighten my evenings :D
By the way, do you plan on repairing your, now dead, Commodore64? If so, could you film the process and upload it? I do like videos of this style, like "searching for the problem, finding it, changing the parts, maybe soldering"
I would imagine I'll eventually do a repair video on it.. I've got to get some of these other projects finished first.
Ok, thank you for answering. I am looking forward to it :)
Have a nice day.
It's nice to know that other people experience projects going south spectacularly like this. Happens to almost everything I decide to try, and I usually give up long before getting to any kind of resolution. So this video was immensely satisfying to watch. Also, one minor correction that I hope you will accept in the spirit it is intended (pedantry is not always a bad thing!): 42 is not the meaning of life, the universe and everything. 42 is the answer to the ultimate question of life, the universe, and everything. The question of course remains a mystery. A small but important difference.
It'd be cool to program Pong on that little screen.
it is a text screen, not a graphical one. So there are large blank fringes around letters - like a "######" pattern that cannot be lit at all because the pixels are not there on the LCD.
Furthermore, it would require constantly reprogramming character generator on-the-fly - possible in theory but slow and hackish.
It would require connecting a graphical LCD with a completely different interface.
Some of these screens allow you to send fonts, which gives you pseudographics.
Pong is quite possible, and possible to run fast.
just get a standard matrix display. much simpler, and looks a lot better
You have to do the if-then-else clause, which would be painfully slow on 64k right?
Love the exercises in trouble shooting. I had many hours of fun using the old ZX-81 and then Sinclair 1000 writing programs that included machine code, building a parallel port that allowed me to make a garden monitor using home brew analog to digital converters and wet and dry bulb thermistors to measure soil humidity to alert when water was needed. Every robotics class could benefit from these basic instructions and trouble shooting methods. Bravo!
Im disappointed there is no part 3 yet but I loved the first two parts. Thanks!!
I love that you show when things go wrong. It's just part of the game when you're tinkering with computers, but it's also a lot of fun to watch.
Using a BASIC program to control the screen makes it slow enough that you can ignore an important requirement of the HD44780 controller chip in the LCD module. That requirement is that you give it enough time to respond to a command before sending the next one. Using toggle switches and a push button gives it plenty of time and, it seems, the BASIC program is slow enough too. But if you write code in assembly language you need to bear in mind that most instructions need at least 37us to execute, and some take as long as 1520us. You can use delays or you can poll the status register of the chip to determine when it's no longer busy before sending the next instruction. Maybe this is covered in part 3. I haven't watched it yet.
The great aspect of the videos in this channel is that the guy shows all the failures unlike others. This is great. We all learn from failures!
can't wait for part 3 and the video about the speach synth
Great video! Love seeing the problems, troubleshooting and solutions. As a equipment maintenance tech in a semiconductor production facility, we deal with these problems on old technology every day! Keep up the great work Dave, love the videos!
I COULD NOT WAIT LONG ENOUGH FOR THIS VIDEO!!!!
only on this channel will you find videos that are this fascinatingly niche and specific. I swear to God I love this guy
11:35 You could actualy connect more than 3 screens. If you used a simple ttl decoder on the last 3 pin, you could connect up to *8* displays !
You do mean 8 displays, right? With something like a 74LS138.
Yes xD i'll correct that
Sure.. and with some shift registers I could add even more. But the point was I could add up to 3 without any additional hardware. Maybe I should have mentioned that.
unless you use shift registers it's actually 7 screens, unless you want to constantly sent signals to the screens ..
u cud controll ovr 9000 screenz with enugh io expendrz
The thing I love about these videos is that you show how no plan survives contact with the enemy.
+8-Bit Guy you can also write a C program to control the parallel port of a PC, it is not that hard. Maybe you can make another episode of controlling an LCD with a PC?
Yeah that's what I wondered about too. I think it can be achieved by BIOS calls, or talking directly with ports (if that's possible).
Its pretty possible to talk directly with ports under linux. I don't know the situation in windows tough. In fact I've written a program for it. I can post it if I find it.
It is still a loooot harder than just typing it in Basic. That was one of the things i stubmbled upon when testing audio-output for Arduino (atmega328), rasperberry Pi (ARMv6) and Saprtan FPGA (3E 250).
arduino was the easiest, spartan you had to do a bit more, and raspberry is a mess in comparison.
ABaumstumpf Check this out: stackoverflow.com/questions/17851461/how-to-access-parallel-port-in-linux
for PC, outputting to port 0x378 should be equivalent to C64's 56577 (did I get these numbers right?)
I like how you show everyone your trial and error. It makes it so much more authentic.
Rest in peace C64.
It ain't dead yet. A simplistic machine like that can survive much more than many of today's computers can. It probably just needs some repairing.
8V on a 5V chip is usually a death sentence for most. Even if chips do survive, it's the question... which ones did? I have arcade boards and once I was diagnosing why one of my boards was having artfacts and random issues, turns out PSU died and sent 7 volts out to the 5V line... That made me sweat but thankfully I caught it in time and seemed to have saved it. Also had one where it inexplicably caught fire when I powered on. Thankfully that was only a tantalum cap that blew.
All of these things leave fear of the formidable power switch and always makes you qustion "Am I sure this is correct" before flicking the switch lol.
Naaaaaa they can be repaired ... issue is BLACK SCREEN could be EVERYTHING in the machine, it the worst scenario for a repair with no info unless you poke some measurements. It a comprehensive machine, schematics are not that easy to read, but for someone who knows about electronics ... it will survive.
You seem to know a bit about it about it. Have you repaired one before? I'm currently working on fixing my C64 but it's a guessing game as to what exactly is wrong. Yes, I have the black screen. I bought a new PLA chip as internet adviced. Made sure I get 5V, check. Still black. Any tips?
Well, I have repaired 3 C64 and read the schematics. Blank screen is the most common sympthon, since machine cant start. I repaired only ONE black screen. I bet hard on PLA, VIC II and ROMS. I have another C64 and the ICs were socketed. All of them tested fine (I was shocked). In this machine was a latch register, like 74245 or similar. The C64 has many glue logic chips around. If you dont have a donor to test, I would first try with a cart. Some of them start fine since the C64 doesnt need to look for ROMS (yes, ROMS go BAD as well). I would take the 6581 out from the system. It not required to start and can take the bus down. When I was child I got black screen and the C64 was found a BAD ROM CHIP. The colprits are the chips that are more stressed, VIC, PLA, and ROMS. Those run hot. One time I got BLACK screen due to a bad connection on the VIC II. The VIC was socketed. And the chip is a toaster. It ended ruining it own socket because the self heating and consuption. But the VIC was fine. Just the 40 DIP socket need to be replaced. It was MELTED on 2 pins. So, take the VIC out and have a look around. The VIC is usually inside a rectangular CAN with a coper finger on the top. RAM, MPU and CIAS ... are less prone to damage There is a color RAM there.
Another thing is the RESET, C64 uses a reset (not sure if made on a 555) chip. This needs to come ok. Easy test: connect the 1541 or 1571 (if you have one) I believe that when the machine is powered on, the reset signal is sent to the 1541 as well. So you will notice it (not enterely sure by now ... to be honest).
I mean this in the nicest possible way, it's really nice to see your mistakes, failures and eventual success. I feel like most RUclipsrs wouldn't be so open to doing so.
Love how a cyber punk track started playing when things started to go awry XD
I really appreciate these videos. I don't understand the subject matter well enough to go out and buy some components and then build stuff, but I understand enough to get the context of the technology. It's cool to see where computing has been and the potential for where we're going. 8 Bit Guy makes it accessible. :)
R.I.P. Dave's C64...
Dave is short for david
I love how clearly you are able to communicate these concepts. I know a lot of the stuff you go through, but i feel like i know it better and feel smarter after watching your videos each time. :)
42 Isn't the MEANING of life, the universe, and everything, it's the ANSWER to life, the universe, and everything.
Ephraim Bane what exactly is it referring to?
its from Hitchhikers Guide to the Galaxy. people built an oracle machine that could answer any question. so they asked it the answer to life, the universe, and everything, and then waited around for like 200 years for it to compute the answer. and the answer it gave was 42. at which point they realized that they would need to ask it what the question was to life, the universe, and everything, in order for the answer to make any sense.
tohopes I wish they hadn’t cancelled the show, really loved the intro. ;
And I noticed that your like count stayed on 42 (wink wink
Google the answer to life and the universe and everything then it come up with 42
Great video! I never really did anything interesting with the user port on my C64 back in the day so it's cool to finally learn about how it works.
I really like how you're not afraid to go into all the setbacks and failed attempts you have in your projects - way better to show how these things go in practice rather than trying to make it look easier than it is!
I can't find Part 3, I'm excited to see it connected to the cartridge port! When is part 3 coming out?
ruclips.net/video/pQk3XgpuaJ4/видео.html
I really appreciate that you show the troubleshooting process. Not everything will go according to plan
make a video on the Commodore 16 or all your Commodores
zoomer vlogs Braydankidgg2 a commodore 16?
he literally mentions the Commodore 16 in the video
He could bang that out easy. Easy like a Sunday morning.
Another great video! I like how you also showed what went wrong and you being so patient with it!
will we see a future build of a voltage "watch dog" to go in line with the C64 power supply. Shouldn't be too hard to get a blinking red LED and cut off.
I really like the fact that it wasn't all edited to "hide" the power supply problem, or reshot... made for a really interesting "real life" video on the topic!
Must leave a like for MR. MEESEEKS! 😄
I love it when there are problems and the electronic music gets dramatic. Great video.
great video. use a 74ls138 for p0, p1, and p2, and get 8 screens going :)
7
I love you show the failures and trouble shooting, it's a good learning tool
Thou shalt check voltages. The world is less another C64.
+heroineworshipper Judging by your comment, the Commodore 64 was released late 1500's-early 1600's time period?
Nah. No electronic computers existed in 1500.
This was more tense and thrilling than literally any sports game I've ever watched.
It was like a high-tech murder mystery. And it was all the power supply with the high voltage rail in the studio. So many different plots all going on at once, all of the plot twists. Will the screen work? Will the second one work? A third? Another computer? 10 10 would watch again.
To quote EEVBlog "Thou shalt check voltages"
i might be late but i like when you go deeper on subjects, pls keep doing this
6:00 - "Make the plan, execute the plan, expect the plan to go off the rails . . . Throw away the plan."
-Leonard Snart
;-)
This takes me back. I used the 8 bits on this port on my c64 and made a pcb that held 8 optoisolators. I connected the switch sides of the optoisolators to the front pcb of a Fisher VCR to increment and decrement the channels and "press" record and tape speed. I lived in Japan on a military base and some local channels had American shows in English if you had a similcast box so I would switch this on or off. We also had one base channel that has just begun showing Star Trek the Next Generation a whole season behind the US. I wrote a program that was a great improvement over the regular VCR programming. I can't believe I was able to figure this out with c64 books back then and no internet. :-)
and my friend complain there computer is to slow for running 4 screens. commodore be like. hold my beer
Mongoloid
I'm so grateful your putting out these videos. Beautifully presented and I'm learning stuff that I've wondered about for many years. Keep up the great work!
42 is not the meaning of life, the universe and everything, it's the answer to the ultimate question.
Me: Has a test
Also me: decides to write 42 for every question
Teacher: I am disappointed in you
Me: 😐
Every video you do on tech stuff is just 100% content. That's awesome! Thank you :)
Very interesting
Truly excellent video, walking through all the problems and showing the solutions really shows you know what you are doing.
That troubleshooting process was some top notch content. And dem tracks was fire cuz
Now im worried about that C64...i doesnt have a fuse or something that can be replaced?
It appears to have a fuse, but fuses don't protect against over-voltage only over-current.
A fuse doesn't cause this kind of problem. More likely a electrolytic capacitor - and replacing them is easy too.
There's a known issue with the C64 power supplies that means that when they go bad, they send too much voltage down the line and fry... I want to say it's the memory, but I'm not 100% sure. I've never run into it myself, but I came across stories about it when I was just looking into getting a less gigantic power brick for my 64.
but the simple fact that the nand gates saw 8+V can mean they probably died.
FETs are extremely fragile to voltage. Simply rubbing your feet on the carpet and touching the pins of a device can kill it.
Cartman - you do realize that ESD is on an entirely different scale and irrelevant when it comes to constant "low" overvoltages?
Cause ESD can easily be more than a couple thousand volts - that can arc over and directly destroy the junction.
I like that you left in your struggles and then how you over came them.
Still waiting for a part three
(yes I know the reference)
Well I'm hooked.... :D
Looking at your videos bring back a lot of sweet memories of my own projects and exploration of the VIC-20/C-64 back in the 80's. My VIC-20 was a bench mule for lot's of funny projects and it did it's final service as a printer server for my BBS in the early 90's :D
I do have a broken down C-64 with a 1541 in the attic, so I'm tempeted to have a go at fixing that!
You should rename the vid to: How to fry an brand new Commodore64
Now that's not nice.
Brand new huw vinicius br é foda viu
really nice video, just recently learned about interfacing an 8051 microcontroller to an lcd at college amd these made things much more clear and intresting
poor little C64 );
I'm sure it's fine, they have an internal regulator for this purpose.
Besides, they're very robust little machines, they'll survive just about anything.
Aio-inc:
Nope. going form 5V to 12 v is a bad bad bad thing. cause yes, you do build some protection into those things, but they are designed to handle 5 v and maybe slight overvoltages. but at 12v even your zener diode will just burn up.
Brick provides two voltages. One is AC and the other is 5V DC regulated. The AC is the one that is rectified and regulated to 12V since VIC uses BOTH 5 and 12V (c64 and 9V on the 64C), cassette is 6V, but it feed from 12V. I believe that SID also uses both. The 5V come from the brick. The reason they have sent AC to the C64 is to provide grid clock (50Hz or 60Hz) to the SID and CIAs. But yes, even when it seems like too much, bet only a couple of thing got damaged, and the rest if fine. I have seen 3.3 micros operated CORRECTLY on near 8V ... MOS ICs (not the brand, but the type) are "more flexible" than TTL. C64 is basically made of MOS chips, but there are some TTL parts as well.
Just de Analog part of it. The digital part runs on 5V, otherwise it will blow everything in the bus. Same is true for VIC II. They are "mixed" signal chips.
I never though such a dramatic video could be made from a topic such as this. I love it.
wheres part 3?