diff --git a/docs/_static/deep-sleep-stub-logic-analyzer-result.png b/docs/_static/deep-sleep-stub-logic-analyzer-result.png new file mode 100644 index 0000000000..937cbe276a Binary files /dev/null and b/docs/_static/deep-sleep-stub-logic-analyzer-result.png differ diff --git a/docs/en/api-guides/deep-sleep-stub.rst b/docs/en/api-guides/deep-sleep-stub.rst index b61e4cb65b..5042957be1 100644 --- a/docs/en/api-guides/deep-sleep-stub.rst +++ b/docs/en/api-guides/deep-sleep-stub.rst @@ -155,3 +155,76 @@ Application Examples .. only:: SOC_RTC_FAST_MEM_SUPPORTED - :example:`system/deep_sleep_wake_stub` demonstrates how to use the Deep-sleep wake stub on {IDF_TARGET_NAME} to quickly perform some tasks (the wake stub code) immediately after wake-up before going back to sleep. + +Measure Time from Deep-sleep Wake-up to Wake Stub Execution +------------------------------------------------------------- + +In certain low-power scenarios, you may want to measure the time it takes for an {IDF_TARGET_NAME} chip to wake up from Deep-sleep to executing the wake stub function. + +This section describes two methods for measuring this wake-up duration. + +Method 1: Estimate Using CPU Cycle Count +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +This method uses the CPU's internal cycle counter to estimate the wake-up time. At the beginning of the stub (with the function type of `esp_deep_sleep_wake_stub_fn_t`), the current CPU cycle count is read and converted into time based on the running CPU frequency. + +Reference example: :example:`system/deep_sleep_wake_stub`. + +After running the example, you will see a log similar to: + +.. code-block:: bash + + Enabling timer wakeup, 10s + Entering deep sleep + ESP-ROM:esp32c3-api1-20210207 + Build:Feb 7 2021 + rst:0x5 (DSLEEP),boot:0xc (SPI_FAST_FLASH_BOOT) + wake stub: wakeup count is 1, wakeup cause is 8, wakeup cost 12734 us + wake stub: going to deep sleep + ESP-ROM:esp32c3-api1-20210207 + Build:Feb 7 2021 + rst:0x5 (DSLEEP),boot:0xc (SPI_FAST_FLASH_BOOT) + +The ``wakeup cost 12734 us`` is time between Deep-sleep wake-up and wake stub execution. + +Advantages: + +- Requires no external hardware. +- Easy to implement. + +Limitations: + +- The measured duration may include part of the initialization flow. +- Not suitable for ultra-precise timing analysis. + +Method 2: Use GPIO pins and Logic Analyzer +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +You can use one GPIO pin as the wake-up source and another GPIO pin to indicate when the wake stub begins execution. By observing the timing between these GPIO transitions on a logic analyzer, you can obtain an accurate measurement of the time from wake-up to stub execution. + +For example, in the screenshot below, GPIO4 functions as the wake-up source, and GPIO5 indicates when the wake stub begins execution. The timing between the high level of GPIO4 and GPIO5 is the time from wake-up to stub execution. + +.. figure:: ../../_static/deep-sleep-stub-logic-analyzer-result.png + :align: center + :alt: Time from Wake-up to Stub Execution + :width: 100% + + Time from Wake-up to Stub Execution + +The ``2.657ms`` is time between Deep-sleep wake-up and wake stub execution. + +Advantages: + +- High accuracy. +- Useful for validating hardware timing behavior. + +Limitations: + +- Requires external equipment (logic analyzer or oscilloscope). +- May require test pin wiring on custom boards. + +Recommendation +^^^^^^^^^^^^^^^^ + +- For quick estimation or software-only testing, Method 1 is sufficient. +- For precise validation and hardware-level timing, Method 2 is recommended. diff --git a/docs/zh_CN/api-guides/deep-sleep-stub.rst b/docs/zh_CN/api-guides/deep-sleep-stub.rst index a6baa39dd6..e47de26d28 100644 --- a/docs/zh_CN/api-guides/deep-sleep-stub.rst +++ b/docs/zh_CN/api-guides/deep-sleep-stub.rst @@ -155,3 +155,76 @@ Deep-sleep 唤醒存根 .. only:: SOC_RTC_FAST_MEM_SUPPORTED - :example:`system/deep_sleep_wake_stub` 演示如何使用 {IDF_TARGET_NAME} 上的深度睡眠唤醒存根,以便在唤醒后立即执行一些任务(唤醒存根代码),然后再返回睡眠状态。 + +测量从 Deep-sleep 唤醒到唤醒存根执行的时间 +--------------------------------------------------- + +在某些低功耗场景下,开发者可能希望测量 {IDF_TARGET_NAME} 芯片从 Deep-sleep 唤醒到执行唤醒存根所需的时间。 + +本节介绍了两种测量该唤醒时长的方法。 + +方法一:使用 CPU 周期计数器估算 +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +该方法利用 CPU 的内部周期计数器来估算唤醒时间。在存根函数(类型为 `esp_deep_sleep_wake_stub_fn_t`)的开头,读取当前的 CPU 周期计数,并根据运行的 CPU 频率将其转换为时间。 + +参考示例::example:`system/deep_sleep_wake_stub`。 + +运行示例后,你将看到类似如下的日志: + +.. code-block:: bash + + Enabling timer wakeup, 10s + Entering deep sleep + ESP-ROM:esp32c3-api1-20210207 + Build:Feb 7 2021 + rst:0x5 (DSLEEP),boot:0xc (SPI_FAST_FLASH_BOOT) + wake stub: wakeup count is 1, wakeup cause is 8, wakeup cost 12734 us + wake stub: going to deep sleep + ESP-ROM:esp32c3-api1-20210207 + Build:Feb 7 2021 + rst:0x5 (DSLEEP),boot:0xc (SPI_FAST_FLASH_BOOT) + +其中 ``wakeup cost 12734 us`` 表示从 Deep-sleep 唤醒到唤醒存根执行之间的时间。 + +方法一的优点: + +- 不需要外部硬件。 +- 实现简单。 + +方法一的局限性: + +- 测量的时长可能包含部分初始化流程。 +- 不适用于超高精度的时序分析。 + +方法二:使用 GPIO 管脚和逻辑分析仪 +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +你可以使用一个 GPIO 管脚作为唤醒源,另一个 GPIO 管脚用于指示唤醒存根开始执行。通过在逻辑分析仪上观察这些 GPIO 的电平变化,可以准确测量从唤醒到存根执行的时间。 + +例如,在下图中,GPIO4 作为唤醒源,GPIO5 用于指示唤醒存根开始执行。GPIO4 和 GPIO5 的高电平之间的时长即为从唤醒到存根执行的时间。 + +.. figure:: ../../_static/deep-sleep-stub-logic-analyzer-result.png + :align: center + :alt: 从唤醒到存根执行的时间 + :width: 100% + + 从唤醒到存根执行的时间 + +其中 ``2.657ms`` 表示从 Deep-sleep 唤醒到唤醒存根执行之间的时间。 + +方法二的优点: + +- 精度高。 +- 适用于验证硬件时序行为。 + +方法二的局限性: + +- 需要外部设备(逻辑分析仪或示波器)。 +- 在定制板上可能需要测试引脚布线。 + +建议 +^^^^^^ + +- 对于快速估算或纯软件测试,方法一已足够。 +- 对于精确验证和硬件级时序分析,推荐使用方法二。