DigitalOut.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #ifndef MBED_DIGITALOUT_H
00023 #define MBED_DIGITALOUT_H
00024 
00025 #include "platform.h"
00026 #include "gpio_api.h"
00027 
00028 namespace mbed {
00029 
00030 /** A digital output, used for setting the state of a pin
00031  *
00032  * Example:
00033  * @code
00034  * // Toggle a LED
00035  * #include "mbed.h"
00036  *
00037  * DigitalOut led(LED1);
00038  *
00039  * int main() {
00040  *     while(1) {
00041  *         led = !led;
00042  *         wait(0.2);
00043  *     }
00044  * }
00045  * @endcode
00046  */
00047 class DigitalOut {
00048 
00049 public:
00050     /** Create a DigitalOut connected to the specified pin
00051      *
00052      *  @param pin DigitalOut pin to connect to
00053      */
00054     DigitalOut(PinName pin) {
00055         gpio_init(&gpio, pin, PIN_OUTPUT);
00056     }
00057 
00058     /** Set the output, specified as 0 or 1 (int)
00059      *
00060      *  @param value An integer specifying the pin output value,
00061      *      0 for logical 0, 1 (or any other non-zero value) for logical 1
00062      */
00063     void write(int value) {
00064         gpio_write(&gpio, value);
00065     }
00066 
00067     /** Return the output setting, represented as 0 or 1 (int)
00068      *
00069      *  @returns
00070      *    an integer representing the output setting of the pin,
00071      *    0 for logical 0, 1 for logical 1
00072      */
00073     int read() {
00074         return gpio_read(&gpio);
00075     }
00076 
00077 #ifdef MBED_OPERATORS
00078     /** A shorthand for write()
00079      */
00080     DigitalOut& operator= (int value) {
00081         write(value);
00082         return *this;
00083     }
00084 
00085     DigitalOut& operator= (DigitalOut& rhs) {
00086         write(rhs.read());
00087         return *this;
00088     }
00089 
00090     /** A shorthand for read()
00091      */
00092     operator int() {
00093         return read();
00094     }
00095 #endif
00096 
00097 protected:
00098     gpio_t gpio;
00099 };
00100 
00101 } // namespace mbed
00102 
00103 #endif
00104