This is a quick tutorial for our 128x64 and 128x32 pixel monochrome OLED displays. These displays are small, only about 1" diagonal, but very readable due to the high contrast of an OLED display. Each OLED display is made of 128x64 or 128x32 individual white OLEDs, each one is turned on or off by the controller chip. Because the display makes its own light, no backlight is required. This reduces the power required to run the OLED and is why the display has such high contrast; we really like this miniature display for its crispness!
The driver chip, SSD1306 can communicate in multiple ways including I2C, SPI and 8-bit parallel. However, only the 128x64 display has all these interfaces available. For the 128x32 OLED, only SPI is available. Frankly, we prefer SPI since its the most flexible and uses a small number of I/O pins so our example code and wiring diagram will use that.