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docs(ble): Optimized the BLE low power guide
This commit is contained in:
Wei Yu Han
@@ -296,7 +296,7 @@ If you have not completed the ESP-IDF development environment setup, please refe
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Try It Out
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^^^^^^^^^^^^^^^^^^
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Please refer to :ref:`Bluetooth LE Introduction Try It Out <nimble_gatt_server_practice>` 。
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Please refer to :ref:`Bluetooth LE Introduction Try It Out <nimble_gatt_server_practice>`.
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Code Explanation
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@@ -8,72 +8,51 @@ This section introduces clock source selection in low power modes for Bluetooth
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Clock Source Selection in Low Power Mode
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--------------------------------------------
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According to the Bluetooth specification, the sleep clock accuracy must be within 500 PPM, so make sure the clock source selected for Bluetooth LE low power mode should meet that requirement. Otherwise Bluetooth LE may not perform normally and cause a series of problem such as ACL connection establishment failure or ACL connection timeout, etc.
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According to the Bluetooth specification, the sleep clock accuracy must be within 500 PPM. Make sure the clock source selected for Bluetooth LE low power mode meets this requirement. Otherwise, Bluetooth LE may not perform normally and can cause a series of problems, such as ACL connection establishment failure or ACL connection timeout.
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Selecting Main XTAL
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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To select the main XTAL as the Bluetooth LE internal clock source, configure the following option:
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.. only:: esp32 or esp32c3 or esp32s3
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.. only:: esp32
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**Configuration Path:**
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:ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` = Main crystal (`CONFIG_BTDM_CTRL_LPCLK_SEL_MAIN_XTAL`)
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``Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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.. only:: esp32c3 or esp32s3
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**Configuration Option:**
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- \ (X) Main crystal
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = Main crystal (`CONFIG_BT_CTRL_LPCLK_SEL_MAIN_XTAL`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
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**Configuration Path:**
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:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use main XTAL as RTC clock source (`CONFIG_BT_LE_LP_CLK_SRC_MAIN_XTAL`)
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``Component config → Bluetooth → Controller Options → BLE low power clock source``
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When this is selected, the main XTAL remains powered on during light-sleep, resulting in higher current consumption. Please refer to :example_file:`Power Save README <bluetooth/nimble/power_save/README.md>` for the typical current consumption in light-sleep using XTAL versus a 32 kHz external crystal.
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**Configuration Option:**
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- \ (X) Use main XTAL as RTC clock source
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When this is selected, the main XTAL remains powered on during light-sleep, resulting in higher current consumption.
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Please refer :example_file:`Power Save README <bluetooth/nimble/power_save/README.md>` for the typical current consumption in light-sleep using XTAL versus a 32kHz external crystal.
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Selecting 32kHz External Crystal
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Selecting 32 kHz External Crystal
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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To use a 32kHz external crystal as the Bluetooth LE internal clock source, configure the following options:
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To use a 32 kHz external crystal as the Bluetooth LE internal clock source, configure the following options:
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.. only:: esp32 or esp32c3 or esp32s3
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**Configuration Path 1:**
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**Configuration Path 1:**
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.. only:: esp32
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``Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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:ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` = External 32 kHz crystal/oscillator (`CONFIG_BTDM_CTRL_LPCLK_SEL_EXT_32K_XTAL`)
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**Configuration Option:**
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.. only:: esp32c3 or esp32s3
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- \ (X) External 32kHz crystal/oscillator
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = External 32 kHz crystal/oscillator (`CONFIG_BT_CTRL_LPCLK_SEL_EXT_32K_XTAL`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
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**Configuration Path 1:**
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``Component config → Bluetooth → Controller Options → BLE low power clock source``
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**Configuration Option:**
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- \ (X) Use system RTC slow clock source
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:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use system RTC slow clock source (`CONFIG_BT_LE_LP_CLK_SRC_DEFAULT`)
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**Configuration Path 2:**
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``Component config → Hardware Settings → RTC Clock Config → RTC clock source``
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**Configuration Option:**
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- \ (X) External 32 kHz crystal
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**Note:** Even if 32kHz is selected in menuconfig, the system will fall back to the main XTAL if the external crystal is not detected during Bluetooth LE initialization. This may lead to unexpected current consumption in light-sleep mode.
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:ref:`CONFIG_RTC_CLK_SRC` = External 32 kHz crystal (`CONFIG_RTC_CLK_SRC_EXT_CRYS`)
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**Note:** Even if 32 kHz is selected in menuconfig, the system will fall back to the main XTAL if the external crystal is not detected during Bluetooth LE initialization. This may lead to unexpected current consumption in light-sleep mode.
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Selecting 136 kHz RC Oscillator
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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@@ -84,11 +63,7 @@ Selecting 136 kHz RC Oscillator
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**Configuration Path 1:**
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`Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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**Configuration Option:**
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- \ (X) Internal 136kHz RC oscillator
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = Internal 136kHz RC oscillator (`CONFIG_BT_CTRL_LPCLK_SEL_RTC_SLOW`)
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Generally, the 136 kHz RC oscillator cannot meet the accuracy requirement of Bluetooth LE. It is only suitable for scenarios with low clock accuracy requirements, such as legacy advertising (ADV) or scanning. It does not support connections in central or peripheral roles.
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@@ -102,25 +77,17 @@ Selecting 136 kHz RC Oscillator
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**Configuration Path 1:**
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``Component config → Bluetooth → Controller Options → BLE low power clock source``
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**Configuration Option:**
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- \ (X) Use system RTC slow clock source
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:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use system RTC slow clock source (`CONFIG_BT_LE_LP_CLK_SRC_DEFAULT`)
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.. only:: not esp32
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**Configuration Path 2:**
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``Component config → Hardware Settings → RTC Clock Config → RTC clock source``
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**Configuration Option:**
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- \ (X) Internal 136 kHz RC oscillator
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:ref:`CONFIG_RTC_CLK_SRC` = Internal 136 kHz RC oscillator (`CONFIG_RTC_CLK_SRC_INT_RC`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
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If low current consumption is required but have no access to the External 32kHz Crystal, then this clock source is recommended. However, selecting this clock source will have the sleep clock accuracy larger than 500 PPM, which is supported if the peer device is also an ESP chip. If the peer device is not an ESP chip, here's some Bluetooth LE event not supported:
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If low current consumption is required but there is no access to the External 32 kHz Crystal, this clock source is recommended. However, this clock source has a sleep clock accuracy exceeding 500 PPM, which is only supported when pairing with another ESP chip. For non-ESP peer devices, the following Bluetooth LE features are not supported:
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1. Central role of Connection
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2. Advertiser of Periodic Advertising
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@@ -129,22 +96,18 @@ Selecting 136 kHz RC Oscillator
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**Configuration Path:**
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``Component config → Bluetooth → Controller Options``
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- :ref:`CONFIG_BT_LE_LL_PEER_SCA_SET_ENABLE` = y
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- :ref:`CONFIG_BT_LE_LL_PEER_SCA` = 3000
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**Configuration Options:**
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- \ [*] Enable to set constant peer SCA
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- \ (3000) Constant peer sleep clock accuracy value
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**Note:** Using the 136 kHz RC oscillator may cause rare issues like connection establishment failure or connection timeout.
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**Note:** Using the 136 kHz RC oscillator may occasionally cause issues such as connection establishment failures or connection timeouts.
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**How to Check the Current Clock Source Used by Bluetooth LE**
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How to Check the Current Clock Source Used by Bluetooth LE
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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You can determine the Bluetooth LE clock source from the logs during Bluetooth LE initialization:
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You can check the current Bluetooth LE clock source from the initialization logs:
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.. list-table:: Bluetooth LE Initialization Log Messages and Clock Source Correspondence
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.. list-table:: Bluetooth LE Initialization Logs and Clock Sources
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:widths: 50 50
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:header-rows: 1
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@@ -163,22 +126,18 @@ You can determine the Bluetooth LE clock source from the logs during Bluetooth L
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FAQ
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--------------------------------------
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**1. Bluetooth LE ACL Connection Fails or Disconnects in Low Power Mode**
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1. Bluetooth LE ACL Connection Fails or Disconnects in Low Power Mode
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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As explained in the clock source selection section above, when ACL connections fail to establish or unexpectedly disconnect in low power mode, first verify whether the current clock source meets Bluetooth LE accuracy requirements.
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**2. Measured light-sleep Current Is Higher Than Expected**
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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2. Measured light-sleep Current Higher Than Expected
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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As introduced in the clock source selection section above, if the main XTAL is used as the clock source, it will remain powered on during light-sleep, resulting in higher current consumption than other clock sources.
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As described in the clock source selection section above, if the main XTAL is used as the clock source, it remains powered on during light-sleep, resulting in higher current consumption than other clock sources. The average current may vary depending on the specific application, Bluetooth LE configuration, and the duration spent in light-sleep. Some applications may have higher average current because Bluetooth LE is active for a larger proportion of the time transmitting and receiving.
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The average current can be application specific, and depends on the Bluetooth LE configuration and the period of time in light-sleep mode. Some application may have larger average current because it has Bluetooth LE taking a larger ratio of time transmitting and receiving.
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**3. Unable to Enter light-sleep Mode**
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3. Unable to Enter light-sleep Mode
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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When Auto light-sleep is enabled but the device fails to enter light-sleep, it's often due to insufficient IDLE duration, which prevents meeting the automatic light-sleep entry conditions.
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This could be caused by excessive logging or Bluetooth LE configuration that prevents sufficient IDLE time, such as continuous scan mode.
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If Auto light-sleep is enabled but the device fails to enter light-sleep, it's usually due to insufficient IDLE time, which prevents the automatic entry conditions from being met. This can be caused by excessive logging or Bluetooth LE configurations that reduce IDLE time, such as continuous scanning.
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@@ -116,7 +116,7 @@ The following drivers hold the ``ESP_PM_APB_FREQ_MAX`` lock while the driver is
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- **Ethernet**: between calls to :cpp:func:`esp_eth_driver_install` and :cpp:func:`esp_eth_driver_uninstall`.
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:SOC_WIFI_SUPPORTED: - **WiFi**: between calls to :cpp:func:`esp_wifi_start` and :cpp:func:`esp_wifi_stop`. If modem sleep is enabled, the lock will be released for the periods of time when radio is disabled.
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:SOC_TWAI_SUPPORTED: - **TWAI**: between calls to :cpp:func:`twai_driver_install` and :cpp:func:`twai_driver_uninstall` (only when the clock source is set to :cpp:enumerator:`TWAI_CLK_SRC_APB`).
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:SOC_BT_SUPPORTED and esp32: - **Bluetooth**: between calls to :cpp:func:`esp_bt_controller_enable` and :cpp:func:`esp_bt_controller_disable`. If Bluetooth Modem-sleep is enabled, the ``ESP_PM_APB_FREQ_MAX`` lock will be released for the periods of time when radio is disabled. However the ``ESP_PM_NO_LIGHT_SLEEP`` lock will still be held, unless :ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` option is set to "External 32kHz crystal".
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:SOC_BT_SUPPORTED and esp32: - **Bluetooth**: between calls to :cpp:func:`esp_bt_controller_enable` and :cpp:func:`esp_bt_controller_disable`. If Bluetooth Modem-sleep is enabled, the ``ESP_PM_APB_FREQ_MAX`` lock will be released for the periods of time when radio is disabled. However the ``ESP_PM_NO_LIGHT_SLEEP`` lock will still be held, unless :ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` option is set to "External 32 kHz crystal".
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:SOC_BT_SUPPORTED and not esp32: - **Bluetooth**: between calls to :cpp:func:`esp_bt_controller_enable` and :cpp:func:`esp_bt_controller_disable`. If Bluetooth Modem-sleep is enabled, the ``ESP_PM_APB_FREQ_MAX`` lock will be released for the periods of time when radio is disabled. However the ``ESP_PM_NO_LIGHT_SLEEP`` lock will still be held.
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:SOC_PCNT_SUPPORTED: - **PCNT**: between calls to :cpp:func:`pcnt_unit_enable` and :cpp:func:`pcnt_unit_disable`.
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:SOC_SDM_SUPPORTED: - **Sigma-delta**: between calls to :cpp:func:`sdm_channel_enable` and :cpp:func:`sdm_channel_disable`.
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@@ -10,70 +10,49 @@
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在低功耗蓝牙应用场景中，由于协议要求休眠时钟精度需在 500 PPM 以内，light-sleep 和 modem-sleep 模式下所用的时钟源必须满足该要求。如果时钟精度不足，可能会出现 ACL 连接失败或超时断开等问题。**因此在使用前请确保所选时钟源及其精度满足要求。**
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选择主晶振
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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要选择主晶振作为低功耗蓝牙内部时钟源，请配置以下选项：
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.. only:: esp32 or esp32c3 or esp32s3
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.. only:: esp32
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**配置路径：**
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:ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` = Main crystal (`CONFIG_BTDM_CTRL_LPCLK_SEL_MAIN_XTAL`)
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``Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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.. only:: esp32c3 or esp32s3
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**配置选项：**
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- \ (X) Main crystal
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = Main crystal (`CONFIG_BT_CTRL_LPCLK_SEL_MAIN_XTAL`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
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**配置路径：**
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:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use main XTAL as RTC clock source (`CONFIG_BT_LE_LP_CLK_SRC_MAIN_XTAL`)
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``Component config → Bluetooth → Controller Options → BLE low power clock source``
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选择主晶振后，light-sleep 模式下主晶振电源不会关闭，因此电流消耗更高。有关使用主晶振与 32 kHz 外部晶振在 light-sleep 模式下的典型电流消耗，请参考 :example_file:`Power Save README <bluetooth/nimble/power_save/README.md>` 。
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**配置选项：**
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- \ (X) Use main XTAL as RTC clock source
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选择主晶振后，light-sleep 模式下主晶振电源不会关闭，因此电流消耗更高。
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有关使用主晶振与 32kHz 外部晶振在 light-sleep 模式下的典型电流消耗，请参考 :example_file:`Power Save README <bluetooth/nimble/power_save/README.md>` 。
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选择 32kHz 外部晶振
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选择 32 kHz 外部晶振
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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要使用 32kHz 外部晶振作为低功耗蓝牙内部时钟源，请配置以下选项：
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要使用 32 kHz 外部晶振作为低功耗蓝牙内部时钟源，请配置以下选项：
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.. only:: esp32 or esp32c3 or esp32s3
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**配置路径 1：**
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**配置路径 1：**
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.. only:: esp32
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``Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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:ref:`CONFIG_BTDM_CTRL_LOW_POWER_CLOCK` = External 32 kHz crystal/oscillator (`CONFIG_BTDM_CTRL_LPCLK_SEL_EXT_32K_XTAL`)
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**配置选项：**
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.. only:: esp32c3 or esp32s3
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- \ (X) External 32kHz crystal/oscillator
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = External 32 kHz crystal/oscillator (`CONFIG_BT_CTRL_LPCLK_SEL_EXT_32K_XTAL`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
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**配置路径 1：**
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``Component config → Bluetooth → Controller Options → BLE low power clock source``
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**配置选项：**
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- \ (X) Use system RTC slow clock source
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:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use system RTC slow clock source (`CONFIG_BT_LE_LP_CLK_SRC_DEFAULT`)
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**配置路径 2：**
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``Component config → Hardware Settings → RTC Clock Config → RTC clock source``
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**配置选项：**
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- \ (X) External 32 kHz crystal
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**注意：** 即使在 menuconfig 中选择了 32kHz 外部晶振，如果低功耗蓝牙初始化时未检测到外部晶振，系统会自动切换为主晶振，可能导致 light-sleep 电流高于预期。
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:ref:`CONFIG_RTC_CLK_SRC` = External 32 kHz crystal (`CONFIG_RTC_CLK_SRC_EXT_CRYS`)
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**注意：** 即使在 menuconfig 中选择了 32 kHz 外部晶振，如果低功耗蓝牙初始化时未检测到外部晶振，系统会自动切换为主晶振，可能导致 light-sleep 电流高于预期。
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选择 136 kHz RC 振荡器
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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@@ -84,11 +63,7 @@
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|
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**配置路径 1：**
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||||
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||||
``Component config → Bluetooth → Controller Options → MODEM SLEEP Options → Bluetooth modem sleep → Bluetooth Modem sleep Mode 1 → Bluetooth low power clock``
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||||
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||||
**配置选项：**
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||||
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||||
- \ (X) Internal 136kHz RC oscillator
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:ref:`CONFIG_BT_CTRL_LOW_POWER_CLOCK` = Internal 136kHz RC oscillator (`CONFIG_BT_CTRL_LPCLK_SEL_RTC_SLOW`)
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一般来说，136 kHz RC 振荡器难以满足低功耗蓝牙的精度要求，仅适用于对时钟精度要求不高的场景，如传统广播 (ADV) 或扫描 (SCAN)。它不支持以中心角色或外设角色建立连接。
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@@ -102,25 +77,17 @@
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**配置路径 1：**
|
||||
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||||
``Component config → Bluetooth → Controller Options → BLE low power clock source``
|
||||
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||||
**配置选项：**
|
||||
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||||
- \ (X) Use system RTC slow clock source
|
||||
:ref:`CONFIG_BT_LE_LP_CLK_SRC` = Use system RTC slow clock source (`CONFIG_BT_LE_LP_CLK_SRC_DEFAULT`)
|
||||
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||||
.. only:: not esp32
|
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**配置路径 2：**
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``Component config → Hardware Settings → RTC Clock Config → RTC clock source``
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**配置选项：**
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||||
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||||
- \ (X) Internal 136 kHz RC oscillator
|
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:ref:`CONFIG_RTC_CLK_SRC` = Internal 136 kHz RC oscillator (`CONFIG_RTC_CLK_SRC_INT_RC`)
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.. only:: esp32c2 or esp32c6 or esp32h2 or esp32c5 or esp32c61
|
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|
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对于需要低功耗且没有 32kHz 外部晶振的场景下，可以选择 136 kHz R C振荡器。然而这个时钟无法满足低功耗蓝牙的 500PPM 的休眠时钟精度需求。不过如果对端设备使用的是 ESP 芯片，仍能支持低功耗蓝牙行为。但是如果对端设备并非使用 ESP 芯片，则使用下面低功耗蓝牙行为将无法支持：
|
||||
对于需要低功耗且没有 32 kHz 外部晶振的场景，可以选择 136 kHz RC 振荡器。然而，该时钟无法满足低功耗蓝牙的 500 PPM 的休眠时钟精度需求。如果对端设备使用 ESP 芯片，低功耗蓝牙功能仍可正常工作；但如果对端设备不是 ESP 芯片，则以下低功耗蓝牙行为将无法支持：
|
||||
|
||||
1. 作为连接的 Central 方
|
||||
2. 作为 Periodic Advertising 的广播方
|
||||
@@ -129,17 +96,13 @@
|
||||
|
||||
**配置路径：**
|
||||
|
||||
``Component config → Bluetooth → Controller Options``
|
||||
|
||||
**配置选项：**
|
||||
|
||||
- \ [*] Enable to set constant peer SCA
|
||||
- \ (3000) Constant peer sleep clock accuracy value
|
||||
- :ref:`CONFIG_BT_LE_LL_PEER_SCA_SET_ENABLE` = y
|
||||
- :ref:`CONFIG_BT_LE_LL_PEER_SCA` = 3000
|
||||
|
||||
**注意：** 使用 136 kHz RC 振荡器可能偶发连接断开或连接失败。
|
||||
|
||||
|
||||
**如何确认当前低功耗蓝牙使用的时钟源**
|
||||
如何确认当前低功耗蓝牙使用的时钟源
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
可通过低功耗蓝牙初始化时的日志判断当前时钟源：
|
||||
@@ -163,22 +126,18 @@
|
||||
常见问题
|
||||
--------------------------------------
|
||||
|
||||
**1. 低功耗蓝牙 ACL 连接在低功耗模式下建立失败或断开**
|
||||
1. 低功耗蓝牙 ACL 连接在低功耗模式下建立失败或断开
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
如时钟源选择部分所述，ACL 连接建立失败或断开时，请首先检查当前时钟源是否满足低功耗蓝牙精度要求。
|
||||
|
||||
|
||||
**2. 实测 light-sleep 电流高于预期**
|
||||
2. 实测 light-sleep 电流高于预期
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
如时钟源选择部分所述，若主晶振为时钟源，light-sleep 模式下主晶振持续供电，电流消耗高于其他时钟源。
|
||||
如时钟源选择部分所述，若主晶振为时钟源，light-sleep 模式下主晶振持续供电，电流消耗高于其他时钟源。平均电流可能会因具体应用而异，并取决于低功耗蓝牙的配置以及处于 light-sleep 模式的时间周期。某些应用的平均电流可能会更大，这是因为低功耗蓝牙在其中花费了更高比例的时间进行发射和接收。
|
||||
|
||||
平均电流可能会因具体应用而异，并取决于低功耗蓝牙的配置以及处于 light-sleep 模式的时间周期。某些应用的平均电流可能会更大，这是因为低功耗蓝牙在其中花费了更高比例的时间进行发射和接收。
|
||||
|
||||
**3. 无法进入 light-sleep 模式**
|
||||
3. 无法进入 light-sleep 模式
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
启用 Auto light-sleep 后，若设备无法进入 light-sleep，通常是 IDLE 时间不足，未满足自动进入条件。
|
||||
|
||||
这可能由日志过多或低功耗蓝牙配置导致 IDLE 时间过短（如连续扫描）引起。
|
||||
启用 Auto light-sleep 后，若设备无法进入 light-sleep，通常是 IDLE 时间不足，未满足自动进入条件。这可能由日志过多或低功耗蓝牙配置导致 IDLE 时间过短（如连续扫描）引起。
|
||||
|
||||
Reference in New Issue
Block a user