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How to get a clock with any frequency at FlexIO I2S module of S32K144?

Question asked by 继鹏 申 on Mar 31, 2020
Latest reply on Apr 8, 2020 by Daniel Martynek

I used Flexio to simulate I2S communication,use SDK example.the SDK example offered a demo for flexio i2s,include 4 pins(SCK,WS,TX,RX),it's a three wires i2s protocol,but now we need a four wires i2s protocol(MCLK,SCK,WS,TX,no need rx),so we need to patch a master clock(MCLK,PTE10) for four wires I2S .Our flexio peripheral clock is 48MHz(or can configure it to 112MHz).we all known,audio signals often require a clock that is not an integer multiple,MCLK = (128,196,256...)* Fs, Fs may equals 22.05kHz,26.8kHz,28.2kHz,44.1kHz...).If we divide from Flexio timer,MCLK will not  produce the frequency I need,because it only has integer multiples frequency.So Is there any other way to get the any frequency I need?In addition,how to ensure that the phase of MCLK we generated is the same as SCK?Looking forward to your reply。Many thanks

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