Even if the breakout board have SPI pins i didn’t use them. For some reasons I didn’t make them work, so I used other 2.8V pins.
So, my connections are:
OLED – Breakout
SCL(SCLK) – E1
SDA(MOSI) – D1
CS – A5
RST – B1
DC – A6
VCC – C5 (2.8V)
GND – GND
One more thing, now the library is using the default font, I didn’t managed to make it work also with other fonts.