Does the display also have buttons on it as datasheet shows ability to interface 16x buttons to the chip?
You will need 3 pins to transmit data to the display chip STB, DIN & CLK and a forth DOUT if your reading the keys attached to the display. It looks like SPI_MODE0 so using the SPI library will take a lot of the grunt work out of programming. Most everything else you need will be in the datasheet but it may be a lot of trial and error to determine how the display is wired up. First thing is to determine what type of display the chip is connected to...
Display Mode Settings:
0000: 4 digits, 12 segments
0011: 5 digits, 11 segments
0100: 6 digits, 10 segments
0101: 7 digits, 9 segments
0110: 8 digits, 8 segments
Maybe a picture will help here.