DigitalOut.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_DIGITALOUT_H
00017 #define MBED_DIGITALOUT_H
00018 
00019 #include "platform.h"
00020 #include "gpio_api.h"
00021 
00022 namespace mbed {
00023 
00024 /** A digital output, used for setting the state of a pin
00025  *
00026  * Example:
00027  * @code
00028  * // Toggle a LED
00029  * #include "mbed.h"
00030  *
00031  * DigitalOut led(LED1);
00032  *
00033  * int main() {
00034  *     while(1) {
00035  *         led = !led;
00036  *         wait(0.2);
00037  *     }
00038  * }
00039  * @endcode
00040  */
00041 class DigitalOut {
00042 
00043 public:
00044     /** Create a DigitalOut connected to the specified pin
00045      *
00046      *  @param pin DigitalOut pin to connect to
00047      */
00048     DigitalOut(PinName pin) {
00049         gpio_init(&gpio, pin, PIN_OUTPUT);
00050     }
00051 
00052     /** Set the output, specified as 0 or 1 (int)
00053      *
00054      *  @param value An integer specifying the pin output value,
00055      *      0 for logical 0, 1 (or any other non-zero value) for logical 1
00056      */
00057     void write(int value) {
00058         gpio_write(&gpio, value);
00059     }
00060 
00061     /** Return the output setting, represented as 0 or 1 (int)
00062      *
00063      *  @returns
00064      *    an integer representing the output setting of the pin,
00065      *    0 for logical 0, 1 for logical 1
00066      */
00067     int read() {
00068         return gpio_read(&gpio);
00069     }
00070 
00071 #ifdef MBED_OPERATORS
00072     /** A shorthand for write()
00073      */
00074     DigitalOut& operator= (int value) {
00075         write(value);
00076         return *this;
00077     }
00078 
00079     DigitalOut& operator= (DigitalOut& rhs) {
00080         write(rhs.read());
00081         return *this;
00082     }
00083 
00084     /** A shorthand for read()
00085      */
00086     operator int() {
00087         return read();
00088     }
00089 #endif
00090 
00091 protected:
00092     gpio_t gpio;
00093 };
00094 
00095 } // namespace mbed
00096 
00097 #endif