test test test
snake-test/mbed/drivers/DigitalIn.h
- Committer:
- mohamedmoawya
- Date:
- 2020-05-25
- Revision:
- 0:e4c5e6ec922e
File content as of revision 0:e4c5e6ec922e:
/* mbed Microcontroller Library * Copyright (c) 2006-2013 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef MBED_DIGITALIN_H #define MBED_DIGITALIN_H #include "platform/platform.h" #include "hal/gpio_api.h" #include "platform/mbed_critical.h" namespace mbed { /** \addtogroup drivers */ /** A digital input, used for reading the state of a pin * * @note Synchronization level: Interrupt safe * * Example: * @code * // Flash an LED while a DigitalIn is true * * #include "mbed.h" * * DigitalIn enable(p5); * DigitalOut led(LED1); * * int main() { * while(1) { * if(enable) { * led = !led; * } * wait(0.25); * } * } * @endcode * @ingroup drivers */ class DigitalIn { public: /** Create a DigitalIn connected to the specified pin * * @param pin DigitalIn pin to connect to */ DigitalIn(PinName pin) : gpio() { // No lock needed in the constructor gpio_init_in(&gpio, pin); } /** Create a DigitalIn connected to the specified pin * * @param pin DigitalIn pin to connect to * @param mode the initial mode of the pin */ DigitalIn(PinName pin, PinMode mode) : gpio() { // No lock needed in the constructor gpio_init_in_ex(&gpio, pin, mode); } /** Read the input, represented as 0 or 1 (int) * * @returns * An integer representing the state of the input pin, * 0 for logical 0, 1 for logical 1 */ int read() { // Thread safe / atomic HAL call return gpio_read(&gpio); } /** Set the input pin mode * * @param pull PullUp, PullDown, PullNone, OpenDrain */ void mode(PinMode pull) { core_util_critical_section_enter(); gpio_mode(&gpio, pull); core_util_critical_section_exit(); } /** Return the output setting, represented as 0 or 1 (int) * * @returns * Non zero value if pin is connected to uc GPIO * 0 if gpio object was initialized with NC */ int is_connected() { // Thread safe / atomic HAL call return gpio_is_connected(&gpio); } /** An operator shorthand for read() * \sa DigitalIn::read() * @code * DigitalIn button(BUTTON1); * DigitalOut led(LED1); * led = button; // Equivalent to led.write(button.read()) * @endcode */ operator int() { // Underlying read is thread safe return read(); } protected: #if !defined(DOXYGEN_ONLY) gpio_t gpio; #endif //!defined(DOXYGEN_ONLY) }; } // namespace mbed #endif