Merge branch 'revert/i2s_apll_pm_type_v5.4' into 'release/v5.4'

fix(i2s): lock APB when using apll with DFS feature (v5.4) See merge request espressif/esp-idf!37144
2025-03-08 15:49:08 -05:00 · 2025-02-20 21:33:39 +08:00 · 2025-02-20 21:33:39 +08:00 · a043a96abb
commit a043a96abb
parent 2fe702e8f7 6f40f19047
11 changed files with 107 additions and 14 deletions
--- a/components/driver/deprecated/i2s_legacy.c
+++ b/components/driver/deprecated/i2s_legacy.c
@ -1479,6 +1479,11 @@ static esp_err_t i2s_init_legacy(i2s_port_t i2s_num, int intr_alloc_flag)
    /* Create power management lock */
 #ifdef CONFIG_PM_ENABLE
    esp_pm_lock_type_t pm_lock = ESP_PM_APB_FREQ_MAX;
+#if SOC_I2S_SUPPORTS_APLL
+    if (p_i2s[i2s_num]->use_apll) {
+        pm_lock = ESP_PM_NO_LIGHT_SLEEP;
+    }
+#endif // SOC_I2S_SUPPORTS_APLL
    ESP_RETURN_ON_ERROR(esp_pm_lock_create(pm_lock, 0, "i2s_driver", &p_i2s[i2s_num]->pm_lock), TAG, "I2S pm lock error");
 #endif //CONFIG_PM_ENABLE

--- a/components/esp_driver_dac/dac_continuous.c
+++ b/components/esp_driver_dac/dac_continuous.c
@ -228,7 +228,7 @@ esp_err_t dac_continuous_new_channels(const dac_continuous_config_t *cont_cfg, d

    /* Create PM lock */
 #if CONFIG_PM_ENABLE
-    esp_pm_lock_type_t pm_lock_type = ESP_PM_APB_FREQ_MAX;
+    esp_pm_lock_type_t pm_lock_type = cont_cfg->clk_src == DAC_DIGI_CLK_SRC_APLL ? ESP_PM_NO_LIGHT_SLEEP : ESP_PM_APB_FREQ_MAX;
    ESP_GOTO_ON_ERROR(esp_pm_lock_create(pm_lock_type, 0, "dac_driver", &handle->pm_lock), err3, TAG, "Failed to create DAC pm lock");
 #endif
    handle->chan_cnt = __builtin_popcount(cont_cfg->chan_mask);
--- a/components/esp_driver_i2s/i2s_pdm.c
+++ b/components/esp_driver_i2s/i2s_pdm.c
@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
@ -202,6 +202,13 @@ esp_err_t i2s_channel_init_pdm_tx_mode(i2s_chan_handle_t handle, const i2s_pdm_t

 #ifdef CONFIG_PM_ENABLE
    esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
+    if (pdm_tx_cfg->clk_cfg.clk_src == I2S_CLK_SRC_APLL) {
+        /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+         * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
+        pm_type = ESP_PM_NO_LIGHT_SLEEP;
+    }
+#endif // SOC_I2S_SUPPORTS_APLL
    ESP_RETURN_ON_ERROR(esp_pm_lock_create(pm_type, 0, "i2s_driver", &handle->pm_lock), TAG, "I2S pm lock create failed");
 #endif

@ -249,8 +256,10 @@ esp_err_t i2s_channel_reconfig_pdm_tx_clock(i2s_chan_handle_t handle, const i2s_
    if (pdm_tx_cfg->clk_cfg.clk_src != clk_cfg->clk_src) {
        ESP_GOTO_ON_ERROR(esp_pm_lock_delete(handle->pm_lock), err, TAG, "I2S delete old pm lock failed");
        esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
-#if SOC_I2S_SUPPORTS_APLL
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
        if (clk_cfg->clk_src == I2S_CLK_SRC_APLL) {
+            /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+             * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
            pm_type = ESP_PM_NO_LIGHT_SLEEP;
        }
 #endif // SOC_I2S_SUPPORTS_APLL
@ -488,8 +497,10 @@ esp_err_t i2s_channel_init_pdm_rx_mode(i2s_chan_handle_t handle, const i2s_pdm_r

 #ifdef CONFIG_PM_ENABLE
    esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
-#if SOC_I2S_SUPPORTS_APLL
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
    if (pdm_rx_cfg->clk_cfg.clk_src == I2S_CLK_SRC_APLL) {
+        /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+         * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
        pm_type = ESP_PM_NO_LIGHT_SLEEP;
    }
 #endif // SOC_I2S_SUPPORTS_APLL
@ -540,8 +551,10 @@ esp_err_t i2s_channel_reconfig_pdm_rx_clock(i2s_chan_handle_t handle, const i2s_
    if (pdm_rx_cfg->clk_cfg.clk_src != clk_cfg->clk_src) {
        ESP_GOTO_ON_ERROR(esp_pm_lock_delete(handle->pm_lock), err, TAG, "I2S delete old pm lock failed");
        esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
-#if SOC_I2S_SUPPORTS_APLL
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
        if (clk_cfg->clk_src == I2S_CLK_SRC_APLL) {
+            /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+             * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
            pm_type = ESP_PM_NO_LIGHT_SLEEP;
        }
 #endif // SOC_I2S_SUPPORTS_APLL
--- a/components/esp_driver_i2s/i2s_std.c
+++ b/components/esp_driver_i2s/i2s_std.c
@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
@ -245,6 +245,13 @@ esp_err_t i2s_channel_init_std_mode(i2s_chan_handle_t handle, const i2s_std_conf

 #ifdef CONFIG_PM_ENABLE
    esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
+    if (std_cfg->clk_cfg.clk_src == I2S_CLK_SRC_APLL) {
+        /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+         * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
+        pm_type = ESP_PM_NO_LIGHT_SLEEP;
+    }
+#endif // SOC_I2S_SUPPORTS_APLL
    ESP_RETURN_ON_ERROR(esp_pm_lock_create(pm_type, 0, "i2s_driver", &handle->pm_lock), TAG, "I2S pm lock create failed");
 #endif

@ -293,8 +300,10 @@ esp_err_t i2s_channel_reconfig_std_clock(i2s_chan_handle_t handle, const i2s_std
    if (std_cfg->clk_cfg.clk_src != clk_cfg->clk_src) {
        ESP_GOTO_ON_ERROR(esp_pm_lock_delete(handle->pm_lock), err, TAG, "I2S delete old pm lock failed");
        esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
-#if SOC_I2S_SUPPORTS_APLL
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
        if (clk_cfg->clk_src == I2S_CLK_SRC_APLL) {
+            /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+             * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
            pm_type = ESP_PM_NO_LIGHT_SLEEP;
        }
 #endif // SOC_I2S_SUPPORTS_APLL
--- a/components/esp_driver_i2s/i2s_tdm.c
+++ b/components/esp_driver_i2s/i2s_tdm.c
@ -254,6 +254,13 @@ esp_err_t i2s_channel_init_tdm_mode(i2s_chan_handle_t handle, const i2s_tdm_conf
 #endif
 #ifdef CONFIG_PM_ENABLE
    esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
+    if (tdm_cfg->clk_cfg.clk_src == I2S_CLK_SRC_APLL) {
+        /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+         * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
+        pm_type = ESP_PM_NO_LIGHT_SLEEP;
+    }
+#endif // SOC_I2S_SUPPORTS_APLL
    ESP_RETURN_ON_ERROR(esp_pm_lock_create(pm_type, 0, "i2s_driver", &handle->pm_lock), TAG, "I2S pm lock create failed");
 #endif

@ -302,8 +309,10 @@ esp_err_t i2s_channel_reconfig_tdm_clock(i2s_chan_handle_t handle, const i2s_tdm
    if (tdm_cfg->clk_cfg.clk_src != clk_cfg->clk_src) {
        ESP_GOTO_ON_ERROR(esp_pm_lock_delete(handle->pm_lock), err, TAG, "I2S delete old pm lock failed");
        esp_pm_lock_type_t pm_type = ESP_PM_APB_FREQ_MAX;
-#if SOC_I2S_SUPPORTS_APLL
+#if SOC_I2S_SUPPORTS_APLL && SOC_I2S_HW_VERSION_2
        if (clk_cfg->clk_src == I2S_CLK_SRC_APLL) {
+            /* Only I2S HW 2 supports to adjust APB frequency while using APLL clock source
+             * HW 1 will have timing issue because the DMA and I2S are under different clock domains */
            pm_type = ESP_PM_NO_LIGHT_SLEEP;
        }
 #endif // SOC_I2S_SUPPORTS_APLL
--- a/components/esp_lcd/i80/esp_lcd_panel_io_i2s.c
+++ b/components/esp_lcd/i80/esp_lcd_panel_io_i2s.c
@ -667,7 +667,7 @@ static esp_err_t i2s_lcd_select_periph_clock(esp_lcd_i80_bus_handle_t bus, lcd_c
    // create pm lock based on different clock source
    // clock sources like PLL and XTAL will be turned off in light sleep
 #if CONFIG_PM_ENABLE
-    ESP_RETURN_ON_ERROR(esp_pm_lock_create(ESP_PM_APB_FREQ_MAX, 0, "i80_bus_lcd", &bus->pm_lock), TAG, "create pm lock failed");
+    ESP_RETURN_ON_ERROR(esp_pm_lock_create(ESP_PM_NO_LIGHT_SLEEP, 0, "i80_bus_lcd", &bus->pm_lock), TAG, "create pm lock failed");
 #endif
    return ESP_OK;
 }
--- a/docs/en/api-reference/peripherals/dac.rst
+++ b/docs/en/api-reference/peripherals/dac.rst
@ -96,7 +96,7 @@ Power Management

 When the power management is enabled (i.e., :ref:`CONFIG_PM_ENABLE` is on), the system will adjust or stop the clock source of DAC before entering Light-sleep mode, thus potential influence to the DAC signals may lead to false data conversion.

-When using DAC driver in continuous mode, it can prevent the system from changing or stopping the clock source in DMA or cosine mode by acquiring a power management lock. The power lock type will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`. Whenever the DAC is converting (i.e., DMA or cosine wave generator is working), the driver guarantees that the power management lock is acquired after calling :cpp:func:`dac_continuous_enable`. Likewise, the driver will release the lock when :cpp:func:`dac_continuous_disable` is called.
+When using DAC driver in continuous mode, it can prevent the system from changing or stopping the clock source in DMA or cosine mode by acquiring a power management lock. When the clock source is generated from APB, the lock type will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`. When the clock source is APLL (only in DMA mode), it will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_NO_LIGHT_SLEEP`. Whenever the DAC is converting (i.e., DMA or cosine wave generator is working), the driver guarantees that the power management lock is acquired after calling :cpp:func:`dac_continuous_enable`. Likewise, the driver will release the lock when :cpp:func:`dac_continuous_disable` is called.

 IRAM Safe
 ^^^^^^^^^
--- a/docs/en/api-reference/peripherals/i2s.rst
+++ b/docs/en/api-reference/peripherals/i2s.rst
@ -243,7 +243,7 @@ Power Management

 When the power management is enabled (i.e., :ref:`CONFIG_PM_ENABLE` is on), the system will adjust or stop the source clock of I2S before entering Light-sleep, thus potentially changing the I2S signals and leading to transmitting or receiving invalid data.

-The I2S driver can prevent the system from changing or stopping the source clock by acquiring a power management lock. The power lock type will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`. Whenever the user is reading or writing via I2S (i.e., calling :cpp:func:`i2s_channel_read` or :cpp:func:`i2s_channel_write`), the driver guarantees that the power management lock is acquired. Likewise, the driver releases the lock after the reading or writing finishes.
+The I2S driver can prevent the system from changing or stopping the source clock by acquiring a power management lock. When the source clock is generated from APB, the lock type will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX` and when the source clock is APLL (if supported), it will be set to :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_NO_LIGHT_SLEEP`. Whenever the user is reading or writing via I2S (i.e., calling :cpp:func:`i2s_channel_read` or :cpp:func:`i2s_channel_write`), the driver guarantees that the power management lock is acquired. Likewise, the driver releases the lock after the reading or writing finishes.

 .. only:: SOC_I2S_SUPPORT_SLEEP_RETENTION

--- a/docs/zh_CN/api-reference/peripherals/dac.rst
+++ b/docs/zh_CN/api-reference/peripherals/dac.rst
@ -96,7 +96,7 @@ DAC 外设中包含一个余弦波发生器，可以在通道上产生余弦波

 启用电源管理时（即开启 :ref:`CONFIG_PM_ENABLE`），系统会在进入 Light-sleep 模式前调整或停止 DAC 时钟源，这可能会影响 DAC 信号，从而导致数据无法正确转换。

-在连续模式下使用 DAC 驱动时，可以通过获取电源管理锁来防止系统在 DMA 或余弦波模式下改变或停止时钟源。电源锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`。在进行 DAC 转换时（即 DMA 或余弦波发生器运行时），驱动程序会保证在调用 :cpp:func:`dac_continuous_enable` 后获取电源管理锁。同样地，在调用 :cpp:func:`dac_continuous_disable` 时，驱动程序会释放锁。
+在连续模式下使用 DAC 驱动时，可以通过获取电源管理锁来防止系统在 DMA 或余弦波模式下改变或停止时钟源。时钟源为 APB 时，锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`。时钟源为 APLL 时（仅在 DMA 模式下），锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_NO_LIGHT_SLEEP`。在进行 DAC 转换时（即 DMA 或余弦波发生器运行时），驱动程序会保证在调用 :cpp:func:`dac_continuous_enable` 后获取电源管理锁。同样地，在调用 :cpp:func:`dac_continuous_disable` 时，驱动程序会释放锁。

 IRAM 安全
 ^^^^^^^^^
--- a/docs/zh_CN/api-reference/peripherals/i2s.rst
+++ b/docs/zh_CN/api-reference/peripherals/i2s.rst
@ -237,7 +237,7 @@ I2S 驱动中的资源可分为三个级别：

 电源管理启用（即开启 :ref:`CONFIG_PM_ENABLE`）时，系统将在进入 Light-sleep 前调整或停止 I2S 时钟源，这可能会影响 I2S 信号，从而导致传输或接收的数据无效。

-I2S 驱动可以获取电源管理锁，从而防止系统设置更改或时钟源被禁用。电源锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`。用户通过 I2S 读写时（即调用 :cpp:func:`i2s_channel_read` 或 :cpp:func:`i2s_channel_write`），驱动程序将获取电源管理锁，并在读写完成后释放锁。
+I2S 驱动可以获取电源管理锁，从而防止系统设置更改或时钟源被禁用。时钟源为 APB 时，锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_APB_FREQ_MAX`。时钟源为 APLL（若支持）时，锁的类型将被设置为 :cpp:enumerator:`esp_pm_lock_type_t::ESP_PM_NO_LIGHT_SLEEP`。用户通过 I2S 读写时（即调用 :cpp:func:`i2s_channel_read` 或 :cpp:func:`i2s_channel_write`），驱动程序将获取电源管理锁，并在读写完成后释放锁。

 .. only:: SOC_I2S_SUPPORT_SLEEP_RETENTION

--- a/examples/peripherals/i2s/i2s_codec/i2s_es7210_tdm/README.md
+++ b/examples/peripherals/i2s/i2s_codec/i2s_es7210_tdm/README.md
@ -5,7 +5,7 @@

 (See the README.md file in the upper level 'examples' directory for more information about examples.)

-I2S on `ESP32S3` and `ESP32C3` supports [TDM mode](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-reference/peripherals/i2s.html#tdm-mode), in which multiple slots can be transmitted by standard I2S connection.
+The targets that listed on the top support [TDM mode](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-reference/peripherals/i2s.html#tdm-mode), in which multiple slots can be transmitted by standard I2S connection.

 This example demonstrates how to use I2S TDM mode to record 4 MICs connected to [ES7210](http://www.everest-semi.com/pdf/ES7210%20PB.pdf) codec. ES7210 has 4 TDM modes, which are `ES7210_I2S_FMT_I2S` `ES7210_I2S_FMT_LJ` `ES7210_I2S_FMT_DSP_A` and `ES7210_I2S_FMT_DSP_B`, and they are all supported by I2S TDM driver. Relation between ES7210 TDM modes and I2S Driver TDM modes is shown in the following table.

@ -91,6 +91,63 @@ I (10431) gpio: GPIO[4]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulld
 I (10431) example: You can now safely remove the card, recorded file is /RECORD.WAV
 ```

+## Application Notes
+
+TDM mode is widely used in multi-channel scenario. Some ADC/DAC (e.g., ES7210 and ES7243) that supports TDM can be cascaded to sample more channels synchronously.
+
+Take ES7210 for example, it is a 4-channel audio ADC that supports TDM. And we can chain upto four ES7210 to form a 16-channel recorder, meanwhile it only needs one I2S port.
+
+You can refer to the connection as follow:
+
+```
+┌───────────────┐
+│      ESP      │
+│               │
+│          MCLK ├───────────┬──────────────────────────────┬──────────────────────────────┬──────────────────────────────┐
+│               │           │                              │                              │                              │
+│          BCLK ├────────┬──┼───────────────────────────┬──┼───────────────────────────┬──┼───────────────────────────┐  │
+│               │        │  │                           │  │                           │  │                           │  │
+│            WS ├─────┬──┼──┼────────────────────────┬──┼──┼────────────────────────┬──┼──┼────────────────────────┐  │  │
+│               │     │  │  │                        │  │  │                        │  │  │                        │  │  │
+│          DOUT │     │  │  │    ┌───────────────┐   │  │  │    ┌───────────────┐   │  │  │    ┌───────────────┐   │  │  │    ┌───────────────┐
+│               │     │  │  │    │   ES7210_0    │   │  │  │    │   ES7210_1    │   │  │  │    │   ES7210_2    │   │  │  │    │   ES7210_3    │
+│           DIN │◄─┐  │  │  │    │               │   │  │  │    │               │   │  │  │    │               │   │  │  │    │               │
+└───────────────┘  │  │  │  └───►│ MCLK          │   │  │  └───►│ MCLK          │   │  │  └───►│ MCLK          │   │  │  └───►│ MCLK          │
+                   │  │  │       │               │   │  │       │               │   │  │       │               │   │  │       │               │
+                   │  │  └──────►│ SCLK          │   │  └──────►│ SCLK          │   │  └──────►│ SCLK          │   │  └──────►│ SCLK          │
+                   │  │          │               │   │          │               │   │          │               │   │          │               │
+                   │  └─────────►│ LRCK          │   └─────────►│ LRCK          │   └─────────►│ LRCK          │   └─────────►│ LRCK          │
+                   │             │               │              │               │              │               │              │               │
+                   └─────────────┤ TDMOUT        │   ┌──────────┤ TDMOUT        │   ┌──────────┤ TDMOUT        │   ┌──────────┤ TDMOUT        │
+                                 │               │   │          │               │   │          │               │   │          │               │
+                            ┌───►│ TDMIN         │   │     ┌───►│ TDMIN         │   │     ┌───►│ TDMIN         │   │          │ TDMIN         │
+                            │    │               │   │     │    │               │   │     │    │               │   │          │               │
+                            │    └───────────────┘   │     │    └───────────────┘   │     │    └───────────────┘   │          └───────────────┘
+                            │                        │     │                        │     │                        │
+                            └────────────────────────┘     └────────────────────────┘     └────────────────────────┘
+```
+
+### How A Frame Formed in This Cascaded Case
+
+Generally, all the ES7210 will send the data that sampled by itself at the beginning of a frame, and then catenate the backward ES7210 data behind. In another word, ES7210_0 will send the data in the order ES7210_0 -> ES7210_1 -> ES7210_2 -> ES7210_3.
+
+See the detailed steps as follows:
+
+1. First 4 channels of the 16 channels:
+    - ES7210_3 send data that sampled by itself to ES7210_2;
+    - ES7210_2 send data that sampled by itself to ES7210_1, store the data sent from ES7210_3;
+    - ES7210_1 send data that sampled by itself to ES7210_0, store the data sent from ES7210_2;
+    - ES7210_0 send data that sampled by itself to ESP, store the data sent from ES7210_1;
+2. Second 4 channels of the 16 channels:
+    - ES7210_2 send the stored data (i.e., sampled by ES7210_3) to ES7210_1;
+    - ES7210_1 send the stored data (i.e., sampled by ES7210_2) to ES7210_0, and store the data from ES7210_2 (i.e., sampled by ES7210_3);
+    - ES7210_0 send the stored data (i.e., sampled by ES7210_1) to ESP, and store the data sent from ES7210_1 (i.e., sampled by ES7210_2);
+3. Third 4 channels of the 16 channels:
+    - ES7210_1 send the stored data (i.e., sampled by ES7210_3) to ES7210_0;
+    - ES7210_0 send the stored data (i.e., sampled by ES7210_2) to ESP, and store the data from ES7210_1 (i.e., sampled by ES7210_3);
+4. Last 4 channels of the 16 channels:
+    - ES7210_0 send the stored data (i.e., sampled by ES7210_3) to ESP;
+
 ## Troubleshooting

 For any technical queries, please open an [issue](https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.