Reply To: Atlas Scientific Dissolved Oxygen Sensor Not Reading

Most I2C devices don’t like having the power to the device cut and the reapplied, which is why the Vcc pin of the Mayfly’s I2C Grove jack is constantly powered.  All the other Grove jacks switch the power on or off, but the I2C jack always has 3.3v, even with the Mayfly is asleep.  So if you’re powering your Atlas board from any of the switched sources, try putting it on the constant 3.3v pin.  If you’ve already tried that, then it’s probably something in the code that’s causing the issue.  I don’t use any of the Atlas products, but a few members here have successfully used them, so perhaps they could share what code and hardware configuration was used? @w3asa @adamgold @fionasouthwell