Re: Adafruit 16-Channel 12-bit PWM/Servo Driver not detected
Let's double-check the ribbon-cable connection. With that in place, take a voltage reading at the breakout's VCC pin. It should be 3.3v, obviously. Thing is, it's possible to connect the ribbon cable to the RasPi's GPIO header in a way that sends the signals to the wrong pins.
Also try `sudo i2cdetect -y 0`, just to see if anything shows up on the other I2C bus. There are some version issues there, too.
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