NIUNIU Self-luminous: needn't backlight, the display can self-luminous; It has high contrast, bright and crisp dots, even tiny fonts quite readable About fonts: no embedded fonts inside the OLED controller, user can create the fonts through the font generation software 1> GND (power ground) 2> VCC (Power + 3.3-5V) 3> D0 (SPI clock line for SPI interface and IIC clock line for IIC interface) 4> D1 (SPI data line for SPI interface and IIC data line for IIC interface) 5> RES (OLED reset, OLED needs to be reset once after power on) 6> DC (SPI data/command selection pin, used to set IIC address when IIC interface) 7> CS (OLED SPI chip selection, active low, must be grounded if not used) Important Note: The OLED display is not used with the LCD screen; the OLED is self-illuminating and has no backlight, so the screen will not have any response when only the power is applied! There must be a correct program operation to display it! Delivery Quantity: 2pcs, Package Contents: Only the above package contents, excluding other products. Dimensions: 27.3 x 27.8mm (Reminder: The size is measured manually, please allow 1-2 cm measurement error) Color: color random delivery (Due to different monitors and lighting effects, the actual color of the item may be slightly different from the color shown on the picture.)