John Karatka / mbed

mbed

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drivers/DigitalIn.h@182:57724642e740, 2018-02-16 (annotated)

Committer:
AnnaBridge
Date:
Fri Feb 16 16:09:33 2018 +0000
Revision:
182:57724642e740
Parent:
167:e84263d55307 
mbed-dev library. Release version 159.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /* mbed Microcontroller Library
<> 149:156823d33999 2 * Copyright (c) 2006-2013 ARM Limited
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 149:156823d33999 5 * you may not use this file except in compliance with the License.
<> 149:156823d33999 6 * You may obtain a copy of the License at
<> 149:156823d33999 7 *
<> 149:156823d33999 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 9 *
<> 149:156823d33999 10 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 149:156823d33999 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 13 * See the License for the specific language governing permissions and
<> 149:156823d33999 14 * limitations under the License.
<> 149:156823d33999 15 */
<> 149:156823d33999 16 #ifndef MBED_DIGITALIN_H
<> 149:156823d33999 17 #define MBED_DIGITALIN_H
<> 149:156823d33999 18
<> 149:156823d33999 19 #include "platform/platform.h"
<> 149:156823d33999 20
<> 149:156823d33999 21 #include "hal/gpio_api.h"
<> 160:d5399cc887bb 22 #include "platform/mbed_critical.h"
<> 149:156823d33999 23
<> 149:156823d33999 24 namespace mbed {
<> 149:156823d33999 25 /** \addtogroup drivers */
<> 149:156823d33999 26
<> 149:156823d33999 27 /** A digital input, used for reading the state of a pin
<> 149:156823d33999 28 *
AnnaBridge 167:e84263d55307 29 * @note Synchronization level: Interrupt safe
<> 149:156823d33999 30 *
<> 149:156823d33999 31 * Example:
<> 149:156823d33999 32 * @code
<> 149:156823d33999 33 * // Flash an LED while a DigitalIn is true
<> 149:156823d33999 34 *
<> 149:156823d33999 35 * #include "mbed.h"
<> 149:156823d33999 36 *
<> 149:156823d33999 37 * DigitalIn enable(p5);
<> 149:156823d33999 38 * DigitalOut led(LED1);
<> 149:156823d33999 39 *
<> 149:156823d33999 40 * int main() {
<> 149:156823d33999 41 * while(1) {
<> 149:156823d33999 42 * if(enable) {
<> 149:156823d33999 43 * led = !led;
<> 149:156823d33999 44 * }
<> 149:156823d33999 45 * wait(0.25);
<> 149:156823d33999 46 * }
<> 149:156823d33999 47 * }
<> 149:156823d33999 48 * @endcode
AnnaBridge 167:e84263d55307 49 * @ingroup drivers
<> 149:156823d33999 50 */
<> 149:156823d33999 51 class DigitalIn {
<> 149:156823d33999 52
<> 149:156823d33999 53 public:
<> 149:156823d33999 54 /** Create a DigitalIn connected to the specified pin
<> 149:156823d33999 55 *
<> 149:156823d33999 56 * @param pin DigitalIn pin to connect to
<> 149:156823d33999 57 */
<> 149:156823d33999 58 DigitalIn(PinName pin) : gpio() {
<> 149:156823d33999 59 // No lock needed in the constructor
<> 149:156823d33999 60 gpio_init_in(&gpio, pin);
<> 149:156823d33999 61 }
<> 149:156823d33999 62
<> 149:156823d33999 63 /** Create a DigitalIn connected to the specified pin
<> 149:156823d33999 64 *
<> 149:156823d33999 65 * @param pin DigitalIn pin to connect to
<> 149:156823d33999 66 * @param mode the initial mode of the pin
<> 149:156823d33999 67 */
<> 149:156823d33999 68 DigitalIn(PinName pin, PinMode mode) : gpio() {
<> 149:156823d33999 69 // No lock needed in the constructor
<> 149:156823d33999 70 gpio_init_in_ex(&gpio, pin, mode);
<> 149:156823d33999 71 }
<> 149:156823d33999 72 /** Read the input, represented as 0 or 1 (int)
<> 149:156823d33999 73 *
<> 149:156823d33999 74 * @returns
<> 149:156823d33999 75 * An integer representing the state of the input pin,
<> 149:156823d33999 76 * 0 for logical 0, 1 for logical 1
<> 149:156823d33999 77 */
<> 149:156823d33999 78 int read() {
<> 149:156823d33999 79 // Thread safe / atomic HAL call
<> 149:156823d33999 80 return gpio_read(&gpio);
<> 149:156823d33999 81 }
<> 149:156823d33999 82
<> 149:156823d33999 83 /** Set the input pin mode
<> 149:156823d33999 84 *
AnnaBridge 167:e84263d55307 85 * @param pull PullUp, PullDown, PullNone, OpenDrain
<> 149:156823d33999 86 */
<> 149:156823d33999 87 void mode(PinMode pull) {
<> 149:156823d33999 88 core_util_critical_section_enter();
<> 149:156823d33999 89 gpio_mode(&gpio, pull);
<> 149:156823d33999 90 core_util_critical_section_exit();
<> 149:156823d33999 91 }
<> 149:156823d33999 92
<> 149:156823d33999 93 /** Return the output setting, represented as 0 or 1 (int)
<> 149:156823d33999 94 *
<> 149:156823d33999 95 * @returns
<> 149:156823d33999 96 * Non zero value if pin is connected to uc GPIO
<> 149:156823d33999 97 * 0 if gpio object was initialized with NC
<> 149:156823d33999 98 */
<> 149:156823d33999 99 int is_connected() {
<> 149:156823d33999 100 // Thread safe / atomic HAL call
<> 149:156823d33999 101 return gpio_is_connected(&gpio);
<> 149:156823d33999 102 }
<> 149:156823d33999 103
<> 149:156823d33999 104 /** An operator shorthand for read()
AnnaBridge 167:e84263d55307 105 * \sa DigitalIn::read()
<> 149:156823d33999 106 */
<> 149:156823d33999 107 operator int() {
<> 149:156823d33999 108 // Underlying read is thread safe
<> 149:156823d33999 109 return read();
<> 149:156823d33999 110 }
<> 149:156823d33999 111
<> 149:156823d33999 112 protected:
<> 149:156823d33999 113 gpio_t gpio;
<> 149:156823d33999 114 };
<> 149:156823d33999 115
<> 149:156823d33999 116 } // namespace mbed
<> 149:156823d33999 117
<> 149:156823d33999 118 #endif