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Diff: drivers/DigitalOut.h
- Revision:
- 149:156823d33999
- Child:
- 160:d5399cc887bb
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/drivers/DigitalOut.h Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,130 @@ +/* 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_DIGITALOUT_H +#define MBED_DIGITALOUT_H + +#include "platform/platform.h" +#include "hal/gpio_api.h" +#include "platform/critical.h" + +namespace mbed { +/** \addtogroup drivers */ +/** @{*/ + +/** A digital output, used for setting the state of a pin + * + * @Note Synchronization level: Interrupt safe + * + * Example: + * @code + * // Toggle a LED + * #include "mbed.h" + * + * DigitalOut led(LED1); + * + * int main() { + * while(1) { + * led = !led; + * wait(0.2); + * } + * } + * @endcode + */ +class DigitalOut { + +public: + /** Create a DigitalOut connected to the specified pin + * + * @param pin DigitalOut pin to connect to + */ + DigitalOut(PinName pin) : gpio() { + // No lock needed in the constructor + gpio_init_out(&gpio, pin); + } + + /** Create a DigitalOut connected to the specified pin + * + * @param pin DigitalOut pin to connect to + * @param value the initial pin value + */ + DigitalOut(PinName pin, int value) : gpio() { + // No lock needed in the constructor + gpio_init_out_ex(&gpio, pin, value); + } + + /** Set the output, specified as 0 or 1 (int) + * + * @param value An integer specifying the pin output value, + * 0 for logical 0, 1 (or any other non-zero value) for logical 1 + */ + void write(int value) { + // Thread safe / atomic HAL call + gpio_write(&gpio, value); + } + + /** Return the output setting, represented as 0 or 1 (int) + * + * @returns + * an integer representing the output setting of the pin, + * 0 for logical 0, 1 for logical 1 + */ + int read() { + // Thread safe / atomic HAL call + return gpio_read(&gpio); + } + + /** 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); + } + + /** A shorthand for write() + */ + DigitalOut& operator= (int value) { + // Underlying write is thread safe + write(value); + return *this; + } + + DigitalOut& operator= (DigitalOut& rhs) { + core_util_critical_section_enter(); + write(rhs.read()); + core_util_critical_section_exit(); + return *this; + } + + /** A shorthand for read() + */ + operator int() { + // Underlying call is thread safe + return read(); + } + +protected: + gpio_t gpio; +}; + +} // namespace mbed + +#endif + +/** @}*/