Xinyuan-LilyGO / LilyGo-EPD47

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Working with MEMS Microphone - INMP411 #31

Open happychriss opened 3 years ago

happychriss commented 3 years ago

I have connected and INMP411microphone to the following pins: BCK=SCK=13 / WS=15, Data=SD=12, Ground=LR , VCC starting from the connector. I am using WIFI to send the data to a server for recording.

I experience a very strong NOISE on this microphone when using on LilyGo-EPD47. Using a Wemos D32 DEV board with same microphone and same settings, the noise is very low.

I have tried several wiring options for the microphone - always with the same result on the EPD :-(

Problem occurs when EPD is enabled or disabled.

I2S Init code used:

  i2s_pin_config_t pin_config = {
            .bck_io_num = 13, //this is BCK pin
            .ws_io_num = 15, // this is LRCK pin
            .data_out_num = I2S_PIN_NO_CHANGE, // this is DATA output pin
            .data_in_num = 12   //DATA IN
    };

     i2s_config_t i2s_config = {
            .mode = (i2s_mode_t) (I2S_MODE_MASTER | I2S_MODE_RX),
            .sample_rate = 16000,
            .bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT,
            .channel_format = I2S_CHANNEL_FMT_ONLY_LEFT, // was I2S_CHANNEL_FMT_RIGHT_LEFT
            .communication_format = i2s_comm_format_t(I2S_COMM_FORMAT_I2S),
            .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
            .dma_buf_count = 4,
            .dma_buf_len = 1024,
            .use_apll = false,
            .tx_desc_auto_clear = false,
            .fixed_mclk = 0
    };

Question: Should I use different pins, different wiring?

Thx a lot,

happychriss commented 3 years ago

Any help would be really appreciated ! Did anybody else have similar problems with a microphone connected to the board?