Most of the times a converter is provided to reduce the number of pins required for the interaction with the display. In my case, I have a simple model that is directly driven using 8 bit data bus.
For this display I created my own low level driver where I use the GPIO pins to drive implement the commands specification. The ST7066U is used for the control of the display so the commands are according to the datasheet of this lcd driver.
The only drawback that I see is the need to power the thing with 5V (3V3 won't work).
A library for this can be found in my github repo: https://github.com/bdmihai/stm32-st7066u