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examples/i2c_oled/README.md

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 box this demo cycles through a few different graphic screens to test out the
 various drawing primitives.
 
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 ## Use
 Connect an SSD1306-based OLED in I2C interface mode to pins PC1 (SCL) and PC2 (SDA)
 of the CH32V003 with proper I2C pullup resistors and observe the various graphic