Hello!
Such a pleasure to find that my personal project being discussed on Arduino forum!
I guess it is already too late and not topical but nevertheless I'll try to address some of your questions:
In order to control VFD display you need only:
- VCC - +5V rail,
- Data In - serial data input,
- CLK - serial data clock.
- And Ground of course.
No need to use:
- Data Out if there is no requirement to read VFD controller's RAM - it is not vital for displaying characters on VFD display,
- STB is already connected to an external oscillator on the same PCB, you don't have to connect it to anything else.
A link to an example of working code for HT16512 is here: Google Code Archive - Long-term storage for Google Code Project Hosting.
TORPO 6312 is almost the same as HT16512 so the code should provide you with general understanding. However, the code contains charset for 16-segment display and looks like you have 7-segment and the number of digits is different - some changes still have to be done.
Regards,
Magictaler