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Merge branch 'docs/update_gpio_hold_en_description' into 'master'

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docs: update description of gpio_hold_en()

See merge request espressif/esp-idf!21834
This commit is contained in:
Krzysztof Budzynski 2023-01-10 15:50:05 +08:00
commit 738600d839
1 changed files with 12 additions and 11 deletions
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23
components/driver/include/driver/gpio.h
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@ -361,19 +361,20 @@ esp_err_t gpio_get_drive_capability(gpio_num_t gpio_num, gpio_drive_cap_t *stren
/**
* @brief Enable gpio pad hold function.
*
* When the pin is set to hold, the state is latched at that moment and will not change no matter how the internal
* signals change or how the IO MUX/GPIO configuration is modified (including input enable, output enable,
* output value, function, and drive strength values). It can be used to retain the pin state through a
* core reset and system reset triggered by watchdog time-out or Deep-sleep events.
* When a GPIO is set to hold, its state is latched at that moment and will not change when the internal
* signal or the IO MUX/GPIO configuration is modified (including input enable, output enable, output value,
* function, and drive strength values). This function can be used to retain the state of GPIOs when the chip
* or system is reset, for example, when watchdog time-out or Deep-sleep events are triggered.
*
* The gpio pad hold function works in both input and output modes, but must be output-capable gpios.
* If pad hold enabled:
* in output mode: the output level of the pad will be force locked and can not be changed.
* in input mode: input read value can still reflect the changes of the input signal.
* This function works in both input and output modes, and only applicable to output-capable GPIOs.
* If this function is enabled:
* in output mode: the output level of the GPIO will be locked and can not be changed.
* in input mode: the input read value can still reflect the changes of the input signal.
*
* The state of the digital gpio cannot be held during Deep-sleep, and it will resume to hold at its default pin state
* when the chip wakes up from Deep-sleep. If the digital gpio also needs to be held during Deep-sleep,
* `gpio_deep_sleep_hold_en` should also be called.
* However, this function cannot be used to hold the state of a digital GPIO during Deep-sleep. Even if this
* function is enabled, the digital GPIO will be reset to its default state when the chip wakes up from
* Deep-sleep. If you want to hold the state of a digital GPIO during Deep-sleep, please call
* `gpio_deep_sleep_hold_en`.
*
* Power down or call `gpio_hold_dis` will disable this function.
*