I'm trying to get a sense of the overall process/algorithm of how data gets sent via parallel. I'll eventually write code to send data from my ATmega168 to my VFD display module. Here's the section on its parallel interface

I get that I have to load the register with the appropriate code to send to the display module, but then, how do I actually "send" it? I know it has something to do with setting a write bit (or is it a read bit? what's doing the reading and what's doing the writing?) Also, it looks like I have to check PBUSY and wait for it to clear before sending, yes?

I did look at the lcd data sheet but there are elements there that don't correspond to my situation (i.e., they talk about communicating with an MCU, but not parallel interface - is that significant? Also, there's an "E" pin with the LCD, not with my display). I'm not sure is these differences are substantial or just semantic.