tmk_core/tool/mbed/mbed-sdk/libraries/mbed/api/DigitalOut.h

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #ifndef MBED_DIGITALOUT_H
  17 #define MBED_DIGITALOUT_H
  18
  19 #include "platform.h"
  20 #include "gpio_api.h"
  21
  22 namespace mbed {
  23
  24 /** A digital output, used for setting the state of a pin
  25  *
  26  * Example:
  27  * @code
  28  * // Toggle a LED
  29  * #include "mbed.h"
  30  *
  31  * DigitalOut led(LED1);
  32  *
  33  * int main() {
  34  *     while(1) {
  35  *         led = !led;
  36  *         wait(0.2);
  37  *     }
  38  * }
  39  * @endcode
  40  */
  41 class DigitalOut {
  42
  43 public:
  44     /** Create a DigitalOut connected to the specified pin
  45      *
  46      *  @param pin DigitalOut pin to connect to
  47      */
  48     DigitalOut(PinName pin) : gpio() {
  49         gpio_init_out(&gpio, pin);
  50     }
  51
  52     /** Create a DigitalOut connected to the specified pin
  53      *
  54      *  @param pin DigitalOut pin to connect to
  55      *  @param value the initial pin value
  56      */
  57     DigitalOut(PinName pin, int value) : gpio() {
  58         gpio_init_out_ex(&gpio, pin, value);
  59     }
  60
  61     /** Set the output, specified as 0 or 1 (int)
  62      *
  63      *  @param value An integer specifying the pin output value,
  64      *      0 for logical 0, 1 (or any other non-zero value) for logical 1
  65      */
  66     void write(int value) {
  67         gpio_write(&gpio, value);
  68     }
  69
  70     /** Return the output setting, represented as 0 or 1 (int)
  71      *
  72      *  @returns
  73      *    an integer representing the output setting of the pin,
  74      *    0 for logical 0, 1 for logical 1
  75      */
  76     int read() {
  77         return gpio_read(&gpio);
  78     }
  79
  80     /** Return the output setting, represented as 0 or 1 (int)
  81      *
  82      *  @returns
  83      *    Non zero value if pin is connected to uc GPIO
  84      *    0 if gpio object was initialized with NC
  85      */
  86     int is_connected() {
  87         return gpio_is_connected(&gpio);
  88     }
  89
  90 #ifdef MBED_OPERATORS
  91     /** A shorthand for write()
  92      */
  93     DigitalOut& operator= (int value) {
  94         write(value);
  95         return *this;
  96     }
  97
  98     DigitalOut& operator= (DigitalOut& rhs) {
  99         write(rhs.read());
 100         return *this;
 101     }
 102
 103     /** A shorthand for read()
 104      */
 105     operator int() {
 106         return read();
 107     }
 108 #endif
 109
 110 protected:
 111     gpio_t gpio;
 112 };
 113
 114 } // namespace mbed
 115
 116 #endif