Confusion with I2C addresses

[Rob F]

Ah yes those confusing addresses. The reason for the confusion is i2cdetect shows hex values for addresses but reef-pi and most documents talk regular decimal number. I always thought it was an addressing issue for that custom cable because it should have worked.

Address 0x63 = 99 in reef-pi driver, this is the pH circuit.

Address 0x40 = 64 in reef-pi driver, this is the onboard pca9685

Address 0x70 = 112 in reef-pi driver, this is also for pca9685. That address will control all pca9685 in the circuit.

Address 0x50 = 80 in reef-pi driver, this is the expansion.

Here's a calculator for addresses.

https://www.rapidtables.com/convert/numb...tml?x=0x50