We are trying to configure the I2S peripheral for working with the ICS-43434 microphone (www.invensense.com/.../), but we are having a hard time fulfill the requirements of the clocks because they conflict with the nRF52832 equations and contraints.
The ICS-43434 has the following requirements: (taken from it's datasheet)
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format = I2S
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sample width = 24-bit
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twos complement
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There must be 64 SCK cycles in each WS stereo frame
Fulfilling the last line is problematic because the nRF52832 says that the SCK is configured like this:
SCK = 2 * LRCK * CONFIG.SWIDTH
Since sample width = 24:
SCK = 2 * LRCK * 24
So simplified:
SCK = 48 * LRCK
And if I understood correctly, this line: "There must be 64 SCK cycles in each WS stereo frame" means that SCK needs to be 64 times LRCK, so SCK = 64 * LRCK
Any idea how to resolve this conflict?
P.S:
I found two other questions that mentioned that but they were never solved: