this youtube works. Oled 0.91 and 0.96 inch both work. Oled can buy in here. The adafruit example is 128×32, need to change to 128×64 for 0.96 inch oled. One thing becareful, 0.96 oled 128×64, the address is still 0x3c, not 0x3d
In Arduino IDE, change the address to “3C”, otherwise won’t work
