From 86a1d579ffd5ee24aacba153cc309338b69d4807 Mon Sep 17 00:00:00 2001 From: Stefan Tauner Date: Sun, 18 Mar 2018 16:37:54 +0100 Subject: [PATCH] docs: add warning to gpio_get_level() On most microcontrollers I have worked with one can retrieve the current state of output GPIO pins. On ESP32 this is not the case if the pad is not explictly configured to route this information into the port by configuring it as input or i/o. Thus add a warning to the API documentation of gpio_get_level(). Merges https://github.com/espressif/esp-idf/pull/1740 --- components/driver/include/driver/gpio.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/components/driver/include/driver/gpio.h b/components/driver/include/driver/gpio.h index 7cace8836a..8246c415ef 100644 --- a/components/driver/include/driver/gpio.h +++ b/components/driver/include/driver/gpio.h @@ -302,6 +302,8 @@ esp_err_t gpio_set_level(gpio_num_t gpio_num, uint32_t level); /** * @brief GPIO get input level * + * @warning If the pad is not configured for input (or input and output) the returned value is always 0. + * * @param 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); * * @return -- 2.40.0