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
See you next year!