Problem esp-idf/components/driver/include/driver/i2s_pdm.h (IDFGH-7660)

[remyhx]

Using ESP-IDF v5.0-dev-3639-gc2ccc383da / master branch on an ESP32 (just updated), I noticed I2S.H is deprecated, so I ported my code to I2S_PDM.H

There is a mistake in the help file https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/i2s.html (in the example "i2s_new_channel(&chan_cfg, &rx_handle, NULL);" should be " i2s_new_channel(&chan_cfg, NULL, &rx_handle);". But it's not the issue now.

For the PDM slot i can only choose I2S_SLOT_MODE_STEREO or I2S_SLOT_MODE_MONO. In mono there is data imported, but just a quiet channel, I need to change it to stereo to hear the sound. I guess the wrong slot (like left/right) is chosen, but I can't change that.

Like the example:

/* Allocate an I2S rx channel */
i2s_chan_config_t chan_cfg = I2S_CHANNEL_DEFAULT_CONFIG(I2S_NUM_0, I2S_ROLE_MASTER);
i2s_new_channel(&chan_cfg, NULL, &rx_handle);

/* Init the channel into PDM RX mode */
i2s_pdm_rx_config_t pdm_rx_cfg = {
    .clk_cfg = I2S_PDM_RX_CLK_DEFAULT_CONFIG(SAMPLE_RATE),
    .slot_cfg = I2S_PDM_RX_SLOT_DEFAULT_CONFIG(I2S_DATA_BIT_WIDTH_16BIT, I2S_SLOT_MODE_STEREO),
    .gpio_cfg = {
        .clk = WS_PIN,
        .din = DATA_IN_PIN,
        .invert_flags = {
            .clk_inv = false,
        },
    },
};

i2s_channel_init_pdm_rx_mode(rx_handle, &pdm_rx_cfg);

i2s_channel_enable(rx_handle); is called once and for reading i2s_channel_read(rx_handle, (char *)buf, AUDIO_BUF, &bytes_read, portMAX_DELAY);
i2s_channel_disable(rx_handle); at the end.

So in stereo I can hear myself, in Mono I can't,

NB: in audicity both channels seem to contain data now. Not in mono..

[L-KAYA]

Hi remyhx, it's glad to hear your feedback! And the new driver currently indeed has some bugs in PDM mode. The issue you mentioned is a known issue and it's already in progress, there will be another update for the I2S soon, thanks for you reporting!

[silelis]

Hello,

I use componentr compatible with 4.4.1 API and it use i2s.h which is deprecioned. Therefor I have compilation errot (fatal error: driver/i2s.h no sutch file or directory).
Is there some way to use legacy drivers in 5.0 api?

[L-KAYA]

Hi @silelis , if you're using IDF v5.0, the legacy I2S driver should still available, you can refer to the test app of the legacy driver.

If there are still any problems, please open an new Github issue, thanks!