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Mayfly SCL and SDA voltage level

Home Forums Mayfly Data Logger Mayfly SCL and SDA voltage level

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    • #14291
      Anonymous
        Hi there. I have ordered a Mayfly board but I’m having some issues finding documentation on what voltage level the SCL and the SDA pins run at. I see on the hardware page for the 0.5 version tha
      • #14292
        Shannon Hicks
        Moderator

          All of the data lines on the Mayfly run at 3.3 volts. The 2.2k resistors on the I2C lines are the pullup resistors that are required per the I2C design spec.

        • #14294
          Anonymous

            Awesome! Thank you for the quick response.

          • #14451
            ehazard
            Participant
              Hello. I’m currently trying to get a sensor working using I2c protocol, and I have a question about the 2.2 kohm resistors on the SDA and SCL lines. Are those resistances automatically enabled,
            • #14454
              Matt Barney
              Participant
                I’m not an expert, but based on the Mayfly schematic (see pins 19 and 20 on t
              • #14460
                Shannon Hicks
                Moderator
                  Matt is correct, the pullup resistors on the I2C bus on the Mayfly board are soldered to the board and can’t be disabled unless you want to unsolder them, which will cause issues if you try to u
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