0.91-inch OLED Display with Arduino Pro Mini 3.3V Tutorial:

Step 1: Hardware need for this project:

0.91-inch OLED Display Module
10 x Jumper wires (Female to Female)
Arduino Pro Mini 3.3V
USB to TTL Serial adapter (Recommend this adapter “DSD TECH USB to TTL Serial Adapter with FTDI FT232RL Chip Compatible with Windows 10, 8, 7 and Mac OS X”)

Step 2: Connect Arduino Pro mini with OLED display by using 4 jumper wires then connect the FTDI adapter.

0.91-inch OLED Display	Arduino pro mini 3.3 V
GND	GND
VCC	VCC
SCL	A5
SDA	A4

FTDI:	Pro mini:
VCC	VCC
GND	GND
TXD	RXI
RXD	TXO
RTS	DTR
CTS	GND

Step 3: Install these 2 libraries to your Arduino IDE: (The adafruit_SSD1306.h and the adafruit_GFX.h ).

Open your Arduino IDE and go to Tools -> Manage Libraries…

The Library Manager window should pop open.
On the Library Manager window, type “SSD1306” in the search box, you should see the “adafruit SSD1306” library as shown in the picture below, click “install” to install this library.
After installing the Adafruit SSD1306, now type “GFX” in the search box, you should see the “adafruit GFX Library” as shown in the picture below, click “install” to install this library.

Step 4: After installing these 2 libraries, restart your Arduino IDE.

Step 5: Connect the FTDI to your computer USB port( make sure Step 2 is correct).

Testing the OLED Display

After wiring the OLED display to the Arduino and installing all required libraries, you can use one example from the library to see if everything is working properly.

In your Arduino IDE, go to File -> Examples –> Adafruit SSD1306 -> ssd1306_128x32_i2c and select the example for the display you’re using to open the sketch.