I2C VS GPIO
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According to the documentation the I2C pins on the Omega are shared with the GPIO pins 20 and 21. Is this correct?
When I try the i2c-tools I don't see any switching on pins 20 or 21. When I use the fast-gpio on pins 20 and 21 the IO responds correctly.
Is there something I need to change to switch the pins functionality? Or am I looking at the wrong IO pins?
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Figured It out, the IO is correct. My issue was I did not have the required pullup resistors on the I2C lines.
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@will-burke
Yes. Unless your I2C device has built in pull-up resistors you should always have a pull-up resistor on each of the I2C SDA and SCL lines. Only one resistor is needed on these lines no matter how many I2C devices you have connected. I2C protocol depends on these lines being pulled high when no I2C device is actively pulling them low.