3310 is using serial interface (1 Data and Clk) as Byte_Butcher mentioned. You have to use SHIFTOUT -command to transfere data to LCD.
Here you can find one 3310 LCD example.

Controllers used in 3310 or variants (8210...) are: PDC8544 (Philips), KS0712 (Samsung) or SED15A2D01 (Seiko-Epson). All are commands wise compatible.

5.39. LCDOUT
"PBP supports LCD modules with a Hitachi 44780 controller or equivalent."

BR,
-Gusse-