SSD1306 : From SPI to I2C

Sometimes you need/want to use I2C rather than SPI
A very popular LCD screen is the SSD1306 Oled 0.96' display
They are cheap and very well supported.

The back looks like this :

The change is easy, link the R8 marks and move the resistor from R3 to R1
These are the marked ones here:

You end up with that 


D0 is now i2c clock
D1 is now I2c data

You need these two + the reset pin and you are good to go.

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