Advantest R6581 DMM VFD reverse engineered and now with ability to drive an OLED. By Mickle T, EEVBlog thread here: https://www.eevblog.com/forum/repair/advantest-r6581-vfd-replacement/
My own input here at the moment is only to import the original project to Visual Studio 2022 / VisualGDB.
VisualGDB available here: https://visualgdb.com
Ian.