LKAYA

PDM RX 16K的采样频率+默认的8倍过采样，对应的采样时钟输出为1.024MHz，SPH0690LM4H数据手册里只给出了这几个频率：  所以可以先试试改变采样频率让采样时钟达到这些频率，比如 24000Hz

如果不是采样问题的话，看这波形有比较大概率是电路上的问题。 > 尝试过修改gpio 上下拉，外部上拉。都会这样。如果.clk_inv = false，有问题的声道就会变。 这个翻转时钟其实就是软件上交换采样通道的顺序，软件上交换会导致有问题的声道也会改变，那对应硬件上就是说有问题的一直是那一路PDM麦克风，另外也能印证软件上其实两路都能正常采样，但是由于硬件上其中一路有问题，导致最终结果有问题。 不知道之前你们用rk平台测的时候硬件电路是否一致，最好对比一下，特别是接地的引脚有没有接错。

PDM TX 和 PDM RX 的时钟方向都是输出，所以现在不支持把 PDM RX 和 PDM TX 作为主从机来传输数据的用法。 另外 PDM 作为脉冲密度调制，不建议作为设备间通信协议传输数字信号，因为通过PDM传输的信号会经过硬件滤波器调制和还原，和原始数据会有一定差异。所以例程中也并没有演示这种用法。

> 我可以理解成： esp32s3 不支持pdm slave模式吗 是的

@pggh Thanks for reporting! Please correct me if my understanding is wrong. You want to know and adjust the digital data send latency to synchronize the DAC output and ADC...

Hi @pggh , I got what you mean, I tested by sending the TX data that starting from `1` and receiving it to check the latency. ## Test Results: **Case...

Hi @h-milz, thanks for reporting! ## Fix Might Help There was indeed an issue about the mclk division while using EXTERNAL source clock, it has been fixed recently in the...

> I'm using a slot width of 32 with the ADC resolution set to 24 Yeah, you are totally right! You need `I2S_MCLK_MULTIPLE_512` in your case. > Can you elaborate...

Hi @timsterc, could you describe more detailedly about the issue? Like, did it can run successfully but the sampled audio seems not correct? Or the program still report error when...

@timsterc Glad to hear that, this issue will keep open~ I'm looking forward to your good news!