Reverse engineering vintage Japanese electronics - a vacuum fluorescent display!
Вставка
- Опубліковано 12 вер 2024
- Get your first audiobook and two Audible originals free when you try Audible for 30 days visit www.audible.co... or text strangeparts to 500 500!
Today we're reverse engineering a piece of vintage Japanese electronics - a vacuum fluorescent display or VFD.
See behind the scenes at Strange Parts:
/ strangepartscom
/ strangeparts_com
/ strangepartscom
(some of the following links are affiliate links)
Gear I use:
Main camera: amzn.to/2BfHqiW
Main lens: amzn.to/2BAysJQ
Other camera: amzn.to/2t1yKWi
360 camera: amzn.to/2UG0ux7
Microphone: amzn.to/2kNCqHg
Backpack: amzn.to/34vk5oj
Repair Toolkit: ifix.gd/2K2B6wI
Music:
Fight On - Pro Reese (licensed through bit.ly/epidemic-sp)
ravellers - Ran the Man (licensed through bit.ly/epidemic-sp)
Edited by auram - / aurxm
#StrangeParts - Наука та технологія
A cool tip for when you're trying to interface with "strange parts" you don't know a lot about and don't want to blow up (especially in the case of messing up inputs and output pins or voltage levels), is to put series resistors (IDK, around 1K) on all digital signals. That way you limit the current if something bad happens (like both ends forcing opposite voltage levels on the same wire). Keep that in your "toolset" :)
Thank you!!
These are the things that you never get taught except in inexplicable places like youtube comments. :)
@@sstorholm Actually
100 ohms is usually enough, and avoids some problems with weak pull ups/downs and higher speed signals, and yeah, you don't get taught this in school
thanks
Bug is he forgot to declare int i = 0, so i takes on a random value probably in the order of millions (negative or positive)
Bingo! I found it a few minutes later.
@@StrangeParts Relatable C programming problems :P
damn too fast for me.
@M. de k. You're correct. But in appearance It's a random number, and it's an easier way to explain in youtube comments.
@@StrangeParts you are the best and my source of inspiration
I really like how you show your difficulties because we all make the same mistakes after all. Cheers !
Well, he does that to make longer videos to get more revenue :)
@@sadiehallinger1401 ^^The glass is half empty kinda guy.^^
@@honey78665 Hello! Well, that's how he makes his cash to travel and smile :)
F
You always run into Hofstadter's law: it always takes longer than you expected, even if you take Hofstadter's law into account.
i just learned something new
WR = the read write pin, with this you select if you want to read or write to/from the display
CS = Chip select this is a very common pin in parallel/serial busses. It lets you wire your parts up into an actual bus. You pull this low (or high depending on the chip) to let the chip know you want to talk to this specific chip.
"Hey, little VFD display, how are you?"
"AAAAAAAAAAAAAAAAAAAAAA"
more like AYAYA AYAYA AYAYA !!!
Why are you running?!?
W/R is generally the Write/read pin and C/S is usually the Clear/Set pin. This is similar to a lot of LCD modules available nowadays. You can also reconfigure the LCD library for Arduino to work with this display.
Missed "= 0" was sneakily added between cuts :D Pretty interesting video, keep up the good work!
Yeah, that's why I added the text about it:) Didn't want you to think I was trying to pull one over on you.
The annoying thing about not initializing a variable is that sometimes it's no problem and sometimes it's messing up everything.
Just wanna let you know I greatly enjoy watching you write and troubleshoot the code. Not boring at all.
If all of your projects were summed up into a couple words it would be, "All my pins are backwards and upside down!!"
Yes, just what my Saturday afternoon was missing. Cheers!
"Gee, I wouldn't wanna break this rare, expensive, and intricately made part"
*waves it around in the air with just three fingers holding it*
Its okay! His name isn't Linus so he should be safe.
'Waves it around' is right - it annoyed the heck out of me the way he waved stuff around so fast, my old eyes can't keep up with that and I found it very annoying.
I swear if VFD prices fly through the roof like how videos by eevblog and HBO cause other products to skyrocket I'm going to come find you Scotty!
Those displays are pretty cool, though I love the little SPI OLED displays. You can get a decent frame rate and display a lot more info on them and colors
Back in 2003/2004 when i was 3/4 years old My dad used to repair TVs,DVD players and VCR and stuff, so he had dozens of dead electronics which he salvaged for parts, and these fluorescent displays were there in the dozens most of them were broken in the desoldering process as he did not have all the proper equipments, one day i saw one these and it was the exact same size that our Scotty have. I took it, looked closely upon it and stared like half and hour on it before my mom screamed from the back and i dropped it because i got scared. And i cried for breaking something so extra ordinary. And as he said that this thing costs around $600 on a site. Then boy i would've been rich if only we knew that there value will fly off like that in the future. Also upon watching this video half way through i realized that the Sony stereo sound system that i have (a thing from 2000) also have this fluorescent display, Which means when it dies and can't be repaired i'll take apart the display in a heartbeat, to see what type or version it actually is.
2:40
While it's true that the 3V3 Arduino Due should be able to drive the display inputs OK, watch out for the 5V levels coming back from the display. The AT91SAM chip used on the Due does not have 5V-tolerant IO pins, AFAIK.
(a lot of these standard LCD chipsets allow you to read *from* the status register or display memory.)
Some series resistors of say 47 Ohms will help protect the Due, but ideally there should be some proper voltage translation, like a 74HC245 or similar.
Just a heads-up, as otherwise it could damage the Due over time.
Also, beware how you handle the VFD board, as it has an inverter on there, and some of them can be surprisingly spicy when they bite. lol
@Mr T. Guru
You missed the part where I said it uses an inverter. ;)
Sure, it wouldn't be thousands of volts, but still a few hundred.
Perhaps only a few milliamps too, but it could still give a surprising shock, especially if it has a HV cap on the output.
It would be somewhat similar to a small laptop backlight inverter...
en.wikipedia.org/wiki/CCFL_inverter
Just something to watch out for if you don't realise it's there.
@Mr T. Guru that won't save you. 30V will instantly kill some semiconductors even if it can only source a microamp.
can't wait to see what you're working on...Cheers from Canada🙋♂️🍁😊
Isn't it fairly clear that it's a pinball machine?
@@Stuart0870 yeah could be😊🙋♂️🍁
This video has gotten me into electronics and microcontrollers and got me interested in Arduinos and all a year and half ago. Thank you, Scotty
" I really dont want to drop this or break it anyway" * proceeds to throw it around like Lego bricks.
So when do we get to see the pinball machine you are working on :P
Patchinko is my guess :)
@@jasonk9779 Definitely Patchinko or Coin Pusher type game
Either slot or pachinko. Yeah, not so secret anymore.
You had the data sheet. This was just engineering not reverse engineering.
12345nametaken no one likes a know it all, leave him be
Are you actually gatekeeping reverse engineering? :)
I feel clickbaited, I came to this video expecting reverse engineering based on the title.
He already had a complete datasheet, nothing needed reversing.
@@halosrusty You don't know electronics do you? It's not something to ignore. Reverse engineering and engineering is a whole new different story.
Totally agree. You can buy similar VFD modules anywhere. They are controlled similar to an LCD module controlled and easily controlled by off the shelf code like Arduino. So nothing vintage or reverse engineered about this.
Title is a bit misleading, it would be reverse engineering if you had no datasheet;) In any case thanks for great quality video!
"Reverse engineering"
_literally has the datasheet_
*dissapointed Bobby rides away on a bike*
Yeah seriously, just because you don't know what you're doing doesn't make it "reverse engineering" ffs
@@priitmolder6475 Actually laughed out loud.
In all fairness.... having the datasheet doesn't magically make it work. Actually implementing the device in itself is very challenging and rewarding. Reverse engineering might not be the correct term. But the skill in interpreting a datasheet and implementing is something I've seen many engineers unable to do...
@@RamjetX Very much OT but I just wanted to say I love your Thrustmaster wheel adapter
As a software developer thats getting his feet wet in the area of electronics / embedded / system programming, this video really did give me new enthusiasm to keep on going. For example, I know bitwise operators in theory, but still can't wrap my head around their use on the PCB at library implementation level. Now I saw how it's done, hehe.
Reverse engineering with datasheet... yeah
Good video ^^
I think I watch you first a year or so ago maybe more? When you had yourself a project old making your own Apple phone from parts that were sold somewhere in China or Japan. Can't even remember what I watched exactly. I'm not a technician but I once took a VCR and computer repair class so I appreciate real technicians, or Engineers like you. I see what you guys do as an art form and I appreciate your intelligence. Sometimes it's like entertainment or like reading a book and seeing someone else's struggle and success. God bless you. Stay safe. Thank you.
1:58 "Regardless, I really don't want to drop this..." Keeps shaking it anyway haha.
I have been there with a random VFD I found in a lab. I didn‘t find a datasheet, so I tried to buzz out all the connections and routes, took me a complete sunday afternoon. But after that I stopped, because I also thought the board on the back is some custom thing I can‘t reverse engineer to show something on the display. So thanks for this interesting and encouraging video, my VFD looked surprisingly similar! If I find it again I might give it another shot.
I dreamed of this and now it's here! Thank you. I even thought, "But does it do Cyryllic?".
Dude, you are not alone in the projects taking longer than you thought and that you are tired of looking at them..... my current one is doing that to me....wish me luck as I wish you luck!
When you printed Hello world. I smiled as well. First thing I did on an Apple IIc. Oh, the memories :D
wr --> probably a write enable pin
cs --> probably a chip select pin
--> pretty standard stuff in serial circuits / ics
Actually, I think they just need to be low for the display to accept the characters
CS and !WR should be set in the inverse order, first !WR and then CS, when you set the signal to CS you are selecting the device to act, and it executes what is on the data/signal lines, !WR is the operation, not write/read, and there's no need to change it, if you aren't going to read from the device leave !WR low and just signal it with CS. You aren't having problems because the arduino is fasther than the display but it may fail if you lower the speed of the arduino, if the !WR signal is high when you set CS and the display reads a R operation it may set data on the bus.
Also, the data lines are set after CS, that's to avoid collisions, if the previous operation is a read and the device has data in the bus and you write before letting the device that a new operation is going to happen (CS goes high) you may end with a short circuit (you put a 0 and the device has a 1 or vice-versa and you're sending +VCC to GND). It's important too that after you set CS low and have finished the operation, put the port pins in input mode, that will place them in a high impedance state and will avoid data collision.
If you want to simplfy and speed up your code (and make it a lot more readable) you can use a single 8 bit port on the arduino instead of scattered pins (per example, on the base Arduino PORTD is pins 0 to 7) so instead of a loop with bit testing and digitalWrites you can do "PORTD = Data", being Data a byte variable with the value you want in the bus.
Finally, I see you are missing A0 from your code (or at least isn't shown) and you should have it, with it you can control the cursor position and select the READ operation type (data or status)
Hope it helps :)
I used these and many other VFD units in slot machines when I was programmer. The Noritake displays are good but the single line 16x1 unit has some timing issues that corrupt the display. I do love VFDs....have a look on UA-cam for a Crazy Fruits UK slot machine and look at the effects we did. My favourite was the "scramble", essentially, pick random characters for the length of the final string, and as randomly displayed characters match the character of the final string, don't change that character again. Keep doing this, with a timer that keeps getting quicker, and the effect looks great. You can also "throb" the display by adjusting the brightness up and down on a timer. I loved these things.
I am collecting also old displays as a hobby. I like vfds very much!
Maybe I build some watch out of Monsanto MAN displays, that are some very small led arrays, worth to take a look on these.
3:55 love the montage music man!
"I could've got this up and running quicker using serial ... but ... why do the easy thing?"
30 seconds earlier: "This project is taking wayyyy longer than expected."
The 3-pin connector is your friend, it's +5V/Serial/GND. If you ground the serial-pin it goes into demo mode and starts printing the ASCII-table one character at a time. If you want to use the serial interface with an Arduino; solder a bridge on J4 and connect TX on the Arduino to the serial-pin on the VFD and you're done. No fancy code required! I think the default baud rate is 19200.
I love VFDs! They are so cool looking.
This guy's always happy, even when he fails. Great personality.
By the way, "Char" is not pronounced as "Char"ed (burned), but "Char"ecter (as in a letter or number) ;)
Speak for yourself, I've never encountered anyone who has pronounced it the second way :D
I'm just thinking logically why would the shorthand for Character be pronounced "Char" (as in "char"red/burnt), wouldn't it make more sense to be pronounced just like the first part or "Char"acter? I donno, maybe i'm just overthinking it. lol
Logic only affects language by sheer coincidence.
Okie-Dokie then. :)
Hi, I think that you would better create a buffer with characters to be able to draw character at specific position, and redraw screen every 16ms (~60 Hz) using hardware timer for interruptions, this don't block the main thread (delay is a blocking function) and will consume less power.
I miss seeing these things. What a cool project.
"i" needs to be initialized such as "i=0" in your case.
@Alparslan Ali Alp not in C
@Alparslan Ali Alp not in C, in C you get a random data value in if it you don't set it to something
I have no idea about advanced electronics or half of what your talking about, but love your videos. good to see someone still thinks 'outside of the box'....and beklives anything is possible. Keep up the amazing work.
Datasheet is here - www.agesys.ro/pdf/CU20026SCPB-T30A-01.pdf
It looks like it's 8 bit parallel only - so Scotty did need to wire up all 8 of those lines. For those playing along at home, it looks like it's compatible with the generic Arduino LCD libarary: www.arduino.cc/en/Reference/LiquidCrystal - still super cool to see him reproduce it!
Came here to say this - *some* VFD chips seem to be compatible with the liquidcrystal library interface :)
Strange parts you keep saying ur working on a secret project but those who have seen most of ur videos and is a huge fan of ur channel and electronics ..... would have a fifty-fifty idea of what the project is ...... but I cant wait for the big reveal ... anyways love your channel and love your work ur a huge inspiration.
Looking forward to it. If its only half as interesting as this one it'll still be an awesome video but I bet its twice as exciting.
Thank you for the video content. Many used customer display cashier machines stored in warehouses contain similar 2x20 VFD screens, hopefully the pinout is the same.
You used to put subtitles in Portuguese, and now there is no more, please put it back, I really like your videos
I’ve hoarded lots of these displays, as they look great and retro cool :0) They are from a time when electronics were built to a high standard. The Sharp EL displays are fun too.
I've got a similar VFD out of an POS terminal. The protocol is an confidental IBM one and i had to reverse engineer the circuit, desolder the main controller chip and sigal the five (!) shift registers directly. An ESP8266 could drive all through an additional shift register (using I2S and DMA). And by this i have pixel level control on the display with (sort of) multiple gray levels :)
I have a new appreciation for the DEVs behind LCD Smartie
The whole video I said to myself "please make it say Hello World" and you did! I'm so happy!
The controller on the VFD is often functionally the same as the HD44780 [compatible] LCD controller that is commonly used, as such the Arduino LCD lib may be able to drive it. I know the Noritake VFD's I've used in the past were compatible, with only some minor tweaks required.
WOW programming 101 , nice addition to the videos!!!
Being an Eighties kid filled to the brim with 8-bit computer BASIC knowledge, am doing very similar experiments with the Colour Maximite instead of the Arduino. I was amused that you made some of the same mistakes I did!
I’ve found that driving the segments directly instead of interfacing with the driver electronics to be more interesting. I’m just farting around with seven-segment displays at the moment, though. Still, using Ben Eater’s technique of pulling the display byte from a small EEPROM to be very fun! Without relying on a driver, I can drive any segments I want. I may try something similar with some sophisticated displays like yours.
I really enjoyed the video. Thanks!
8 switches and a button to write to a 20x2 lcd display. It is awesome to see self discovery for a project like this with vintage hardware.
Fran Blanche might interest you with the vintage things as well
Back at it again!!!
I'm always excited to watch StrangeParts! Love the way that every video feels like an Adventure that the viewer is part of!A treat really! Keep up the great work!! :D
Both the arduino and the display have [0.1/2.54] headers. When you are working on something new, use jumper wires.
Wire a PCB after you have something working.
If you don't know what signals are, look for other parallel port display drivers.
Hint CS= Chip select the bar means "active LOW" WR means write
@14:37 You should pay attention to the timing at the bottom left of the data sheet. When writing to the VFD controllers, you need to have a delay of 160ns. This is to give the controller time to read the information. Also the ~CS (Active LOW) is indeed Chip Select. The ~WR (Active LOW) is Write/Read. The way I understand the timing is as follows. Send data to D7-D0 and hold for 100ns. 10ns after your sent D7-D0, pull ~WR low for 160ns. You should be able to speed up your display this way.
My Two Cents. Good work in back-engineering the communication with the VFD. This display works similar to the HD44780 LCD controller. The only different is that the HD44780 has an initialization sequence you must complete which puts it either in 8 bit mode of 4 bit mode.
5 minutes, 1000 views and 35 comments. Typical signs of a successfully growing channels :)
Dude, its Scotty. These aren't 'uploads' they're events!
Hi. Looks very similar to working with those HD44780 type LCD displays, in fact this is probably like a grandfather to these modules. To be complete, and to be able to do the progress bar type graphic, you'll need to implement a standard backspace operation (on these things it may act more like a left arrow operation on a PC / Mac), a clear screen operation, and if it supports it, a means of positioning the cursor anywhere on the display. Speaking of, you might want to turn off the underscore cursor, almost certainly possible. This'll just involve sending special characters or commands.
Ive heard 100's of audible ads but since they sponsor you I'm finally going to try it out. My fear is I love it too much tho. It's why I haven't tried it until right after this video.
W/R is Write/Read.
The logic level on this determines if you're writing to the registers or reading from them.
Yes, you can read the content of your Display Controller, which is rarely needed :)
Please "NEVER STOPS TO MAKE VIDEOS"!!!! your vides is like endorphin to nerds brains!!!! I love it so much! every discovery!, every fantastic place you visit!,every fail! is so fantastic, you a kind of person! plese never stops your work! never stops to do vídeos about it! afterall you is the man to put headphones back in iphones when apple said is impossible! so yopu ar a impossible man! thanks to share your adventures! we love it so much!
Very cool video. Thanks!
Just a couple of remarks:
1. The Arduino delay() function takes an integer parameter (of type unsigned long). If you want delays shorter than 1 ms, you can use delayMicroseconds().
2. Instead of defining sendChar() and print(), you could easily implement your own class derived from the abstract Print class. You only have to implement the method `size_t write(uint8_t)` (basically your sendChar()), and then you inherit all the print() methods you enjoy with Serial, including those that convert numbers to ASCII for displaying.
By the way, you can import your current sketch into Atmel Studio, and connect via JTAG to your Arduino Due. This will let you step through and debug your software. It will also still let you use Arduino's libraries. Doing this will wipe the bootloader from the chip as you'll be directly programming it and you'll also need an Atmel-ICE to program the chip and debug it. It might take a little bit to setup, but it's well worth it for the ease of programming/debugging it'll give later. Especially for big projects!
I have to prototype a bunch of projects at work with Arduinos, and I never use their IDE anymore.
agree on the pricing and yes they are impressive little works of solid state art
You can still buy VFD screens new, they also have i2c models with controllers within the glass. They're also comparably priced compared to LCD or OLED technology in bulk manufacturing.
WR / CS is most likely Write / Chip Select, a way to tell the chip what you're sending is intended for it. In many cases (not all) this will be a low select, indicated by a horizontal line on top of CS
It never ceases to amaze me how big and complex boards used to be for how little they actually did. If you really want a challenge you should look inside my original atari table top asteroids arcade machine. There's some huge boards inside and it might be one step up from pong graphically lol. I'm yet to tackle it.. it works but the scoring will randomly insert letters for numbers lol.
Those old vfd displays are so cool. I have a number of them, myself. I used my old hp 48 serial port to drive them and used a 40 char. multi line unit to display reminders for myself and other timely info. Too bad they’re no longer made. I considered making a large display with a pile of dot matrix led displays but when I toted up the cost of building it I decided it was way, wat too much money. These were really cheap when they initially showed up on the surplus market. Thanks for making the video
Awesome stuff, Scotty! Did you consider using an open source library to handle various print routines (as opposed to "println" at all times)? I assume it's often useful to just change out a single character in a line to avoid those delays/flickers when refreshing the entire screen at once(?)
I haven't gone too far down that road yet. Just simple prints is fine for my purposes at the moment.
enjoyed this so much more than the whole ATM Jackpot video. Would love to see more in-depth videos on your projects.
When Scotty does the double air punch and YEA. That moment is why we do this stuff!
Looks like the displays they put in those public payphones that were pretty much everywhere (at least up here in Canada) until the 2000s when cellphones became common...
Investing so much time when there lcd version of this display around for a 1$ with arduino libraries and hardware already figured out. Same data protocol, same character codes probably. Only difference extra power requirements for emitters and grid. You probably never stumble upon them, but that old design based of hitachi hd44780 is still in production and popular.
VFD's are so fun to play with.
who says WERE POPULAR!? VFD modules like yours are in current production in Japan to this day!
Arduino Blog sent me. Cool project, man. I remember having a stereo and a calculator with similar displays back in the late 80's-early 90's. I think my dad's car stereo had one as well.
It is such an exciting moment when it whirs to life!
I remember these displays where popular in car radio's a few years back. Really enjoyed the video by the way.
From my experience with shift registers, when dealing with low frequency arduinos, you don't really need to delay. I tried it once and reduced the delay and expected the registers to hickup at some point.
But the overhead of arduino (and even in native AVR-C) together with the slow clock is often enough to provide proper and reliable latching of the data.
better safe than sorry
Well I guess if the shift registers maximum clock frequency is above the microcontrollers main clock, I'd rather save some valuable processing time...
Btw. is your profile picture the brutally faceswopped version of Tom?
If you're interested, I reverse engineered a Noritake Itron display. Easy to send data to and a surprisingly well written data sheet.
@Strange Parts
You should look up data on the HD47780 character LCD's. Those are almost certain pin compatible with the VFD you're using and there is a ton of information about using a HD47780 with the Arduino.
Thank you Audible, very cool.
Enjoyed you adding the coding part to the video!! Very interesting stuff.
you make it work, and I imagine you have cpu cycles to spare, but just a useful trick: If you look up port manipulation for the Arduino, you will find that digital IO is grouped into ports of 8 bits. You can write to all 8 bits at once. Since your device uses ASCII for the normal letters and the Arduino language also uses ASCII, you can just do PORTX = 'a' to set all the pins to the right value to show an a. This is of course contingent on you wiring the data pins on your device in order to pins 0-7.
Excellent technical skill.
It's so cool that you got the display to print. Can't wait to see the secret project!
love watching these videos
You can bind it with Arduino officialized LCD library. this Library is commonly used for that Arduino LCD, such as Hitachi 20x2 Character LCD display.
Whoa that's so cool.
I see stacks of hard drives. When you gonna call Linus?
Love your work, but you're late on a project and you make the VFD a BFD? Jump to the serial port where it's easier to send w/less code and you don't need so many pins. I've had enough fun driving things like Maxim 7219 chips in nybble mode that I just don't have enough hair to pull anymore. At least this display makes using UTF-8/ASCII easy to code for.
Looking forward to seeing the result and I've gotta admit I love reverse-engineering as much as development. Sometimes I am amazed at things I learn doing so and sometimes amazed they got it to ship! Great use of existing assemblies and Googling useful doc to do so. Great sport!
CS = Chip select WR = Write pin. Usually these get pulled low to enable A) selecting the device (If you have several on the same data bus (D0-D7) ) and B) Choosing between reading data from a register, or writing data into a register. Before you discovered the in mapping being wrong, I actually thought that you maybe hadn't set the display configuration registers. Many displays usually have special registers, where if you flip bits in them, will change how things work, and can do stuff like inverse characters, blank display etc etc. It all depends on the display used.
Also, a downside to these old VFDs, is they do dim over time, and burn out. Thats partly why they fell out of favour, long term reliability isn't good. Best stock some spares.
What happened to you since that iPhone video? Back then you seemed to not know that much about electronics and stuff. Now this, wow!
your projects are Dreams work for us
Already love audible. Listening to a lot of the Star Wars extended universe by Timothy Zahn. Nice choice of sponsor for sure. Glad to hear that you keep working on the project.