GPIO & RTC GPIO¶
Overview¶
The ESP32 chip features 40 physical GPIO pads. Some GPIO pads cannot be used or do not have the corresponding pin on the chip package(refer to technical reference manual). Each pad can be used as a general purpose I/O or can be connected to an internal peripheral signal.
Note that GPIO6-11 are usually used for SPI flash.
GPIO34-39 can only be set as input mode and do not have software pullup or pulldown functions.
There is also separate “RTC GPIO” support, which functions when GPIOs are routed to the “RTC” low-power and analog subsystem. These pin functions can be used when in deep sleep, when the Ultra Low Power co-processor is running, or when analog functions such as ADC/DAC/etc are in use.
Application Example¶
GPIO output and input interrupt example: peripherals/gpio.
API Reference - Normal GPIO¶
Header File¶
Functions¶
-
esp_err_t
gpio_config
(const gpio_config_t *pGPIOConfig)¶ GPIO common configuration.
Configure GPIO’s Mode,pull-up,PullDown,IntrType
- Return
ESP_OK success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
pGPIOConfig
: Pointer to GPIO configure struct
-
esp_err_t
gpio_reset_pin
(gpio_num_t gpio_num)¶ Reset an gpio to default state (select gpio function, enable pullup and disable input and output).
- Note
This function also configures the IOMUX for this pin to the GPIO function, and disconnects any other peripheral output configured via GPIO Matrix.
- Return
Always return ESP_OK.
- Parameters
gpio_num
: GPIO number.
-
esp_err_t
gpio_set_intr_type
(gpio_num_t gpio_num, gpio_int_type_t intr_type)¶ GPIO set interrupt trigger type.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number. If you want to set the trigger type of e.g. of GPIO16, gpio_num should be GPIO_NUM_16 (16);intr_type
: Interrupt type, select from gpio_int_type_t
-
esp_err_t
gpio_intr_enable
(gpio_num_t gpio_num)¶ Enable GPIO module interrupt signal.
- Note
Please do not use the interrupt of GPIO36 and GPIO39 when using ADC or Wi-Fi with sleep mode enabled. Please refer to the comments of
adc1_get_raw
. Please refer to section 3.11 of ‘ECO_and_Workarounds_for_Bugs_in_ESP32’ for the description of this issue. As a workaround, call adc_power_acquire() in the app. This will result in higher power consumption (by ~1mA), but will remove the glitches on GPIO36 and GPIO39.- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number. If you want to enable an interrupt on e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);
-
esp_err_t
gpio_intr_disable
(gpio_num_t gpio_num)¶ Disable GPIO module interrupt signal.
- Return
ESP_OK success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number. If you want to disable the interrupt of e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);
-
esp_err_t
gpio_set_level
(gpio_num_t gpio_num, uint32_t level)¶ GPIO set output level.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO number error
- Parameters
gpio_num
: GPIO number. If you want to set the output level of e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);level
: Output level. 0: low ; 1: high
-
int
gpio_get_level
(gpio_num_t gpio_num)¶ GPIO get input level.
- Warning
If the pad is not configured for input (or input and output) the returned value is always 0.
- Return
0 the GPIO input level is 0
1 the GPIO input level is 1
- Parameters
gpio_num
: GPIO number. If you want to get the logic level of e.g. pin GPIO16, gpio_num should be GPIO_NUM_16 (16);
-
esp_err_t
gpio_set_direction
(gpio_num_t gpio_num, gpio_mode_t mode)¶ GPIO set direction.
Configure GPIO direction,such as output_only,input_only,output_and_input
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO error
- Parameters
gpio_num
: Configure GPIO pins number, it should be GPIO number. If you want to set direction of e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);mode
: GPIO direction
-
esp_err_t
gpio_set_pull_mode
(gpio_num_t gpio_num, gpio_pull_mode_t pull)¶ Configure GPIO pull-up/pull-down resistors.
Only pins that support both input & output have integrated pull-up and pull-down resistors. Input-only GPIOs 34-39 do not.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG : Parameter error
- Parameters
gpio_num
: GPIO number. If you want to set pull up or down mode for e.g. GPIO16, gpio_num should be GPIO_NUM_16 (16);pull
: GPIO pull up/down mode.
-
esp_err_t
gpio_wakeup_enable
(gpio_num_t gpio_num, gpio_int_type_t intr_type)¶ Enable GPIO wake-up function.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number.intr_type
: GPIO wake-up type. Only GPIO_INTR_LOW_LEVEL or GPIO_INTR_HIGH_LEVEL can be used.
-
esp_err_t
gpio_wakeup_disable
(gpio_num_t gpio_num)¶ Disable GPIO wake-up function.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_isr_register
(void (*fn)(void *), void *arg, int intr_alloc_flags, gpio_isr_handle_t *handle, )¶ Register GPIO interrupt handler, the handler is an ISR. The handler will be attached to the same CPU core that this function is running on.
This ISR function is called whenever any GPIO interrupt occurs. See the alternative gpio_install_isr_service() and gpio_isr_handler_add() API in order to have the driver support per-GPIO ISRs.
To disable or remove the ISR, pass the returned handle to the interrupt allocation functions.
- Parameters
fn
: Interrupt handler function.intr_alloc_flags
: Flags used to allocate the interrupt. One or multiple (ORred) ESP_INTR_FLAG_* values. See esp_intr_alloc.h for more info.arg
: Parameter for handler functionhandle
: Pointer to return handle. If non-NULL, a handle for the interrupt will be returned here.
- Return
ESP_OK Success ;
ESP_ERR_INVALID_ARG GPIO error
ESP_ERR_NOT_FOUND No free interrupt found with the specified flags
-
esp_err_t
gpio_pullup_en
(gpio_num_t gpio_num)¶ Enable pull-up on GPIO.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_pullup_dis
(gpio_num_t gpio_num)¶ Disable pull-up on GPIO.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_pulldown_en
(gpio_num_t gpio_num)¶ Enable pull-down on GPIO.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_pulldown_dis
(gpio_num_t gpio_num)¶ Disable pull-down on GPIO.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_install_isr_service
(int intr_alloc_flags)¶ Install the driver’s GPIO ISR handler service, which allows per-pin GPIO interrupt handlers.
This function is incompatible with gpio_isr_register() - if that function is used, a single global ISR is registered for all GPIO interrupts. If this function is used, the ISR service provides a global GPIO ISR and individual pin handlers are registered via the gpio_isr_handler_add() function.
- Return
ESP_OK Success
ESP_ERR_NO_MEM No memory to install this service
ESP_ERR_INVALID_STATE ISR service already installed.
ESP_ERR_NOT_FOUND No free interrupt found with the specified flags
ESP_ERR_INVALID_ARG GPIO error
- Parameters
intr_alloc_flags
: Flags used to allocate the interrupt. One or multiple (ORred) ESP_INTR_FLAG_* values. See esp_intr_alloc.h for more info.
-
void
gpio_uninstall_isr_service
()¶ Uninstall the driver’s GPIO ISR service, freeing related resources.
-
esp_err_t
gpio_isr_handler_add
(gpio_num_t gpio_num, gpio_isr_t isr_handler, void *args)¶ Add ISR handler for the corresponding GPIO pin.
Call this function after using gpio_install_isr_service() to install the driver’s GPIO ISR handler service.
The pin ISR handlers no longer need to be declared with IRAM_ATTR, unless you pass the ESP_INTR_FLAG_IRAM flag when allocating the ISR in gpio_install_isr_service().
This ISR handler will be called from an ISR. So there is a stack size limit (configurable as “ISR stack size” in menuconfig). This limit is smaller compared to a global GPIO interrupt handler due to the additional level of indirection.
- Return
ESP_OK Success
ESP_ERR_INVALID_STATE Wrong state, the ISR service has not been initialized.
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO numberisr_handler
: ISR handler function for the corresponding GPIO number.args
: parameter for ISR handler.
-
esp_err_t
gpio_isr_handler_remove
(gpio_num_t gpio_num)¶ Remove ISR handler for the corresponding GPIO pin.
- Return
ESP_OK Success
ESP_ERR_INVALID_STATE Wrong state, the ISR service has not been initialized.
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number
-
esp_err_t
gpio_set_drive_capability
(gpio_num_t gpio_num, gpio_drive_cap_t strength)¶ Set GPIO pad drive capability.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number, only support output GPIOsstrength
: Drive capability of the pad
-
esp_err_t
gpio_get_drive_capability
(gpio_num_t gpio_num, gpio_drive_cap_t *strength)¶ Get GPIO pad drive capability.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number, only support output GPIOsstrength
: Pointer to accept drive capability of the pad
-
esp_err_t
gpio_hold_en
(gpio_num_t gpio_num)¶ Enable gpio pad hold function.
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: the input value read will not change, regardless the changes of input signal.
The state of digital gpio cannot be held during Deep-sleep, and it will resume the hold function 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.Power down or call gpio_hold_dis will disable this function.
- Return
ESP_OK Success
ESP_ERR_NOT_SUPPORTED Not support pad hold function
- Parameters
gpio_num
: GPIO number, only support output-capable GPIOs
-
esp_err_t
gpio_hold_dis
(gpio_num_t gpio_num)¶ Disable gpio pad hold function.
When the chip is woken up from Deep-sleep, the gpio will be set to the default mode, so, the gpio will output the default level if this function is called. If you dont’t want the level changes, the gpio should be configured to a known state before this function is called. e.g. If you hold gpio18 high during Deep-sleep, after the chip is woken up and
gpio_hold_dis
is called, gpio18 will output low level(because gpio18 is input mode by default). If you don’t want this behavior, you should configure gpio18 as output mode and set it to hight level before callinggpio_hold_dis
.- Return
ESP_OK Success
ESP_ERR_NOT_SUPPORTED Not support pad hold function
- Parameters
gpio_num
: GPIO number, only support output-capable GPIOs
-
void
gpio_deep_sleep_hold_en
(void)¶ Enable all digital gpio pad hold function during Deep-sleep.
When the chip is in Deep-sleep mode, all digital gpio will hold the state before sleep, and when the chip is woken up, the status of digital gpio will not be held. Note that the pad hold feature only works when the chip is in Deep-sleep mode, when not in sleep mode, the digital gpio state can be changed even you have called this function.
Power down or call gpio_hold_dis will disable this function, otherwise, the digital gpio hold feature works as long as the chip enter Deep-sleep.
-
void
gpio_deep_sleep_hold_dis
(void)¶ Disable all digital gpio pad hold function during Deep-sleep.
-
void
gpio_iomux_in
(uint32_t gpio_num, uint32_t signal_idx)¶ Set pad input to a peripheral signal through the IOMUX.
- Parameters
gpio_num
: GPIO number of the pad.signal_idx
: Peripheral signal id to input. One of the*_IN_IDX
signals insoc/gpio_sig_map.h
.
-
void
gpio_iomux_out
(uint8_t gpio_num, int func, bool oen_inv)¶ Set peripheral output to an GPIO pad through the IOMUX.
- Parameters
gpio_num
: gpio_num GPIO number of the pad.func
: The function number of the peripheral pin to output pin. One of theFUNC_X_*
of specified pin (X) insoc/io_mux_reg.h
.oen_inv
: True if the output enable needs to be inversed, otherwise False.
Structures¶
-
struct
gpio_config_t
¶ Configuration parameters of GPIO pad for gpio_config function.
Public Members
-
uint64_t
pin_bit_mask
¶ GPIO pin: set with bit mask, each bit maps to a GPIO
-
gpio_mode_t
mode
¶ GPIO mode: set input/output mode
-
gpio_pullup_t
pull_up_en
¶ GPIO pull-up
-
gpio_pulldown_t
pull_down_en
¶ GPIO pull-down
-
gpio_int_type_t
intr_type
¶ GPIO interrupt type
-
uint64_t
Macros¶
-
GPIO_SEL_0
¶ Pin 0 selected
-
GPIO_SEL_1
¶ Pin 1 selected
-
GPIO_SEL_2
¶ Pin 2 selected
- Note
There are more macros like that up to pin 39, excluding pins 20, 24 and 28..31. They are not shown here to reduce redundant information.
-
GPIO_IS_VALID_GPIO
(gpio_num)¶ Check whether it is a valid GPIO number
-
GPIO_IS_VALID_OUTPUT_GPIO
(gpio_num)¶ Check whether it can be a valid GPIO number of output mode
Enumerations¶
-
enum
gpio_num_t
¶ Values:
-
GPIO_NUM_NC
= -1¶ Use to signal not connected to S/W
-
GPIO_NUM_0
= 0¶ GPIO0, input and output
-
GPIO_NUM_1
= 1¶ GPIO1, input and output
-
GPIO_NUM_2
= 2¶ GPIO2, input and output
- Note
There are more enumerations like that up to GPIO39, excluding GPIO20, GPIO24 and GPIO28..31. They are not shown here to reduce redundant information.
- Note
GPIO34..39 are input mode only.
-
-
enum
gpio_int_type_t
¶ Values:
-
GPIO_INTR_DISABLE
= 0¶ Disable GPIO interrupt
-
GPIO_INTR_POSEDGE
= 1¶ GPIO interrupt type : rising edge
-
GPIO_INTR_NEGEDGE
= 2¶ GPIO interrupt type : falling edge
-
GPIO_INTR_ANYEDGE
= 3¶ GPIO interrupt type : both rising and falling edge
-
GPIO_INTR_LOW_LEVEL
= 4¶ GPIO interrupt type : input low level trigger
-
GPIO_INTR_HIGH_LEVEL
= 5¶ GPIO interrupt type : input high level trigger
-
GPIO_INTR_MAX
¶
-
-
enum
gpio_mode_t
¶ Values:
-
GPIO_MODE_DISABLE
= GPIO_MODE_DEF_DISABLE¶ GPIO mode : disable input and output
-
GPIO_MODE_INPUT
= GPIO_MODE_DEF_INPUT¶ GPIO mode : input only
-
GPIO_MODE_OUTPUT
= GPIO_MODE_DEF_OUTPUT¶ GPIO mode : output only mode
-
GPIO_MODE_OUTPUT_OD
= ((GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD))¶ GPIO mode : output only with open-drain mode
-
GPIO_MODE_INPUT_OUTPUT_OD
= ((GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT) | (GPIO_MODE_DEF_OD))¶ GPIO mode : output and input with open-drain mode
-
GPIO_MODE_INPUT_OUTPUT
= ((GPIO_MODE_DEF_INPUT) | (GPIO_MODE_DEF_OUTPUT))¶ GPIO mode : output and input mode
-
-
enum
gpio_pullup_t
¶ Values:
-
GPIO_PULLUP_DISABLE
= 0x0¶ Disable GPIO pull-up resistor
-
GPIO_PULLUP_ENABLE
= 0x1¶ Enable GPIO pull-up resistor
-
-
enum
gpio_pulldown_t
¶ Values:
-
GPIO_PULLDOWN_DISABLE
= 0x0¶ Disable GPIO pull-down resistor
-
GPIO_PULLDOWN_ENABLE
= 0x1¶ Enable GPIO pull-down resistor
-
-
enum
gpio_pull_mode_t
¶ Values:
-
GPIO_PULLUP_ONLY
¶ Pad pull up
-
GPIO_PULLDOWN_ONLY
¶ Pad pull down
-
GPIO_PULLUP_PULLDOWN
¶ Pad pull up + pull down
-
GPIO_FLOATING
¶ Pad floating
-
-
enum
gpio_drive_cap_t
¶ Values:
-
GPIO_DRIVE_CAP_0
= 0¶ Pad drive capability: weak
-
GPIO_DRIVE_CAP_1
= 1¶ Pad drive capability: stronger
-
GPIO_DRIVE_CAP_2
= 2¶ Pad drive capability: default value
-
GPIO_DRIVE_CAP_DEFAULT
= 2¶ Pad drive capability: default value
-
GPIO_DRIVE_CAP_3
= 3¶ Pad drive capability: strongest
-
GPIO_DRIVE_CAP_MAX
¶
-
API Reference - RTC GPIO¶
Header File¶
Functions¶
-
static bool
rtc_gpio_is_valid_gpio
(gpio_num_t gpio_num)¶ Determine if the specified GPIO is a valid RTC GPIO.
- Return
true if GPIO is valid for RTC GPIO use. false otherwise.
- Parameters
gpio_num
: GPIO number
-
esp_err_t
rtc_gpio_init
(gpio_num_t gpio_num)¶ Init a GPIO as RTC GPIO.
This function must be called when initializing a pad for an analog function.
- Return
ESP_OK success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_deinit
(gpio_num_t gpio_num)¶ Init a GPIO as digital GPIO.
- Return
ESP_OK success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
uint32_t
rtc_gpio_get_level
(gpio_num_t gpio_num)¶ Get the RTC IO input level.
- Return
1 High level
0 Low level
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_set_level
(gpio_num_t gpio_num, uint32_t level)¶ Set the RTC IO output level.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)level
: output level
-
esp_err_t
rtc_gpio_set_direction
(gpio_num_t gpio_num, rtc_gpio_mode_t mode)¶ RTC GPIO set direction.
Configure RTC GPIO direction, such as output only, input only, output and input.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)mode
: GPIO direction
-
esp_err_t
rtc_gpio_pullup_en
(gpio_num_t gpio_num)¶ RTC GPIO pullup enable.
This function only works for RTC IOs. In general, call gpio_pullup_en, which will work both for normal GPIOs and RTC IOs.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_pulldown_en
(gpio_num_t gpio_num)¶ RTC GPIO pulldown enable.
This function only works for RTC IOs. In general, call gpio_pulldown_en, which will work both for normal GPIOs and RTC IOs.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_pullup_dis
(gpio_num_t gpio_num)¶ RTC GPIO pullup disable.
This function only works for RTC IOs. In general, call gpio_pullup_dis, which will work both for normal GPIOs and RTC IOs.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_pulldown_dis
(gpio_num_t gpio_num)¶ RTC GPIO pulldown disable.
This function only works for RTC IOs. In general, call gpio_pulldown_dis, which will work both for normal GPIOs and RTC IOs.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_hold_en
(gpio_num_t gpio_num)¶ Enable hold function on an RTC IO pad.
Enabling HOLD function will cause the pad to latch current values of input enable, output enable, output value, function, drive strength values. This function is useful when going into light or deep sleep mode to prevent the pin configuration from changing.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_hold_dis
(gpio_num_t gpio_num)¶ Disable hold function on an RTC IO pad.
Disabling hold function will allow the pad receive the values of input enable, output enable, output value, function, drive strength from RTC_IO peripheral.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12)
-
esp_err_t
rtc_gpio_isolate
(gpio_num_t gpio_num)¶ Helper function to disconnect internal circuits from an RTC IO This function disables input, output, pullup, pulldown, and enables hold feature for an RTC IO. Use this function if an RTC IO needs to be disconnected from internal circuits in deep sleep, to minimize leakage current.
In particular, for ESP32-WROVER module, call rtc_gpio_isolate(GPIO_NUM_12) before entering deep sleep, to reduce deep sleep current.
- Return
ESP_OK on success
ESP_ERR_INVALID_ARG if GPIO is not an RTC IO
- Parameters
gpio_num
: GPIO number (e.g. GPIO_NUM_12).
-
void
rtc_gpio_force_hold_dis_all
()¶ Disable force hold signal for all RTC IOs.
Each RTC pad has a “force hold” input signal from the RTC controller. If this signal is set, pad latches current values of input enable, function, output enable, and other signals which come from the RTC mux. Force hold signal is enabled before going into deep sleep for pins which are used for EXT1 wakeup.
-
esp_err_t
rtc_gpio_set_drive_capability
(gpio_num_t gpio_num, gpio_drive_cap_t strength)¶ Set RTC GPIO pad drive capability.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number, only support output GPIOsstrength
: Drive capability of the pad
-
esp_err_t
rtc_gpio_get_drive_capability
(gpio_num_t gpio_num, gpio_drive_cap_t *strength)¶ Get RTC GPIO pad drive capability.
- Return
ESP_OK Success
ESP_ERR_INVALID_ARG Parameter error
- Parameters
gpio_num
: GPIO number, only support output GPIOsstrength
: Pointer to accept drive capability of the pad
-
esp_err_t
rtc_gpio_wakeup_enable
(gpio_num_t gpio_num, gpio_int_type_t intr_type)¶ Enable wakeup from sleep mode using specific GPIO.
- Return
ESP_OK on success
ESP_ERR_INVALID_ARG if gpio_num is not an RTC IO, or intr_type is not one of GPIO_INTR_HIGH_LEVEL, GPIO_INTR_LOW_LEVEL.
- Parameters
gpio_num
: GPIO numberintr_type
: Wakeup on high level (GPIO_INTR_HIGH_LEVEL) or low level (GPIO_INTR_LOW_LEVEL)
-
esp_err_t
rtc_gpio_wakeup_disable
(gpio_num_t gpio_num)¶ Disable wakeup from sleep mode using specific GPIO.
- Return
ESP_OK on success
ESP_ERR_INVALID_ARG if gpio_num is not an RTC IO
- Parameters
gpio_num
: GPIO number