Software, end result
The firmware for the AVR is fairly simple. It contains a font (in this case a map of which segments to turn on at which ascii-character), and some logic to scan the display. (This is a, as Noritake calls it, 'dynamic drive'-display, which means the digits have to be displayed one at a time.) To feed the data, it contains a routine to get the characters from the serial line at 11520 baud and scroll them across the screen if the message is too long. For the boostconverter there's a small routine to adjust the pwm-value that gets sent to the mosfet dependant on if the AIN1 voltage is over or under the reference voltage of 1.1V.
If you happen to have the same VFD as I have, or if you want to borrow the font or some routines, the code is leechable from my server, as always. It's licensed under the GPLv3.
I decided to build the VFD into my mp3-machine, and it looks quite cool there;
somewhat steam-punk-ish actually. Btw, my mp3-machine is one of the WT300s
that was left over from my cluster of them.
And finally, because this article is written on christmas eve, a shout-out to all my
readers:
See you next year!
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20 commentsNice work! Very clever implementation -- especially the simple solution for generating the filament and 15V rails.
Would this work with an iv-18 tube vfd?
Thanks so much for sharing this, excellent work! This is simple, efficient and very clever (both the schematic and the code). I just adapted the code for an ATmega328, whatever components I had on hand, and my 9 digit/16 segments VFD, which required one more 4094. It worked very well. The one thing I need to improve is the filament biasing, as it should be made in AC: in DC there is a notable drop in brightness from the - end to the + end of the tube. Still, this saved me many hours of design and debugging, particularly the 15V power supply design and software.
Nice mod. What software are you running on that computer? I\'d like to try and set something like this up as a car stereo, preferably adding a radio to the mix as well
Nice mod. What software are you running on that computer? I\'d like to try and set something like this up as a car stereo, preferably adding a radio to the mix as well
bruce25649: My guess is that you missed the schematic being clickable :)
This is a very useful site; I have been interested in VFDs for some time and have a lot put by, but havnt got round to doing anything yet ( where have you heard that before? ) However, it was very let down by the sloppy circuit diagram which is amateurish and virtually unreadable. All that effort and genius on the electronics let down I fear. I hope that isnt too harsh. Good luck with future work Bruce
pretty amazing stuff :) You could also try using the optocouplers from dead modems for the grid drives as it might make for a more compact circuit. As for the inverter, I've used a surplus mini alarm of the reed switch variety and removed the speaker, rectified the output and found a nice >400V offload output that can then be used. -A
And a USB programer as my computer has no paralel port, or a sereal port as I have a USB to sereal converter. Or even how build them. thanks
Thanks I will need to look into AVR, any ideas where I can get AVR chips in the UK £
At the moment I am trying to build a VFD clock with an old VCR VFD, with out programing (don't know how to program), its a hard chalenge but so far I have made good progress. Its just finding the time to work on it. I am using HCF4026BE 7 segment drivers, I need a 12 hour reset circet to reset it every 12 houres. If someone could help I would be very happy as I have figgered everything elce out.
Not really; you'll always need something to store the character set in. Flashing an AVR isn't hard, though: in the simplest scenario you'll only need 5 wires from your parralell port as a programmer.
exelent work I love it, but can you build a VFD driver that dose not requirer programing? I don't have acses to programing facilertys sadly. :)
Hmm, that last comment didnt sound quite how I wanted it to! Anyway, Amazing work as always is what I meant to say. Im continualy impressed with your ability to work with nothing and produce wonders. Of course using a display with built in controller is no where near as cool as yours. For the rest of us simple folk however, its an practicle alternative...
Yay, great mod. However, i Have several of these displays with onboard controller from Fruit machines. All 16 character with serial input and 5v drive. Ive used them many times on micro controller circuits, id recommend using a 16char (similar to the standard 1line LCDs) VFD from an old fruit machine as its exremely easy to interface and they have the font and control routines built in.
Probleem met VFD's uit random meuk is niet de controller, maar meestal dat er behalve een paar cijfertjes voor tijd alleen rare logo's en streepjes op zitten, wat helemaal niet zo leuk is om te hacken.
Yeah, VPRO tune FTW!
wel Jeroen dat is weer eens knap gedaan echt weer zo'n hebbe ding gemaakt met wat rondslingerend materiaal ik heb ook nog wat van die schermpjes liggen altijd leuk om in toestellen in te bouwen ik vind het echt en tof idee
Nice writeup, and nice background music on your vid! Limewire, here I come!
Nice project! Thank's alot. I was made a test with my 6th digits VFD display and work fine.