how o work with pdm microphone
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Hi there, I cannot understand why pdm microphones cannot be used with a PA Hub. connected to a atom S3. would it be better with a pb Hub? instead?Have an idea?
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PA Hub is a I2C expander. That means it modifies/replaces the device addresses so it can handle more devices even with the same address. To make this work the software has to decode the "new" address of the device.
PB Hub is a GPIO expander. That means, it simple adds GPIO ports and convert them to one upstream I2C. As with the PA Hub the software has to decode the data.
PDM microphones usually have an output which is electrical close to I2C but still different in the data part (e.g. no addressing). PA Hub is for I2C so it will not work. PB Hub may work if it is fast enough to read the clock and data and decoding the data stream on the Controller. I'm not sure if this is really fast enough.
