Gan likun / mbed-dev

00

drivers/DigitalOut.h@0:13413ea9a877, 2022-06-12 (annotated)

Committer:
ganlikun
Date:
Sun Jun 12 14:02:44 2022 +0000
Revision:
0:13413ea9a877
00

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ganlikun 0:13413ea9a877 1 /* mbed Microcontroller Library
ganlikun 0:13413ea9a877 2 * Copyright (c) 2006-2013 ARM Limited
ganlikun 0:13413ea9a877 3 *
ganlikun 0:13413ea9a877 4 * Licensed under the Apache License, Version 2.0 (the "License");
ganlikun 0:13413ea9a877 5 * you may not use this file except in compliance with the License.
ganlikun 0:13413ea9a877 6 * You may obtain a copy of the License at
ganlikun 0:13413ea9a877 7 *
ganlikun 0:13413ea9a877 8 * http://www.apache.org/licenses/LICENSE-2.0
ganlikun 0:13413ea9a877 9 *
ganlikun 0:13413ea9a877 10 * Unless required by applicable law or agreed to in writing, software
ganlikun 0:13413ea9a877 11 * distributed under the License is distributed on an "AS IS" BASIS,
ganlikun 0:13413ea9a877 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
ganlikun 0:13413ea9a877 13 * See the License for the specific language governing permissions and
ganlikun 0:13413ea9a877 14 * limitations under the License.
ganlikun 0:13413ea9a877 15 */
ganlikun 0:13413ea9a877 16 #ifndef MBED_DIGITALOUT_H
ganlikun 0:13413ea9a877 17 #define MBED_DIGITALOUT_H
ganlikun 0:13413ea9a877 18
ganlikun 0:13413ea9a877 19 #include "platform/platform.h"
ganlikun 0:13413ea9a877 20 #include "hal/gpio_api.h"
ganlikun 0:13413ea9a877 21 #include "platform/mbed_critical.h"
ganlikun 0:13413ea9a877 22
ganlikun 0:13413ea9a877 23 namespace mbed {
ganlikun 0:13413ea9a877 24 /** \addtogroup drivers */
ganlikun 0:13413ea9a877 25
ganlikun 0:13413ea9a877 26 /** A digital output, used for setting the state of a pin
ganlikun 0:13413ea9a877 27 *
ganlikun 0:13413ea9a877 28 * @note Synchronization level: Interrupt safe
ganlikun 0:13413ea9a877 29 *
ganlikun 0:13413ea9a877 30 * Example:
ganlikun 0:13413ea9a877 31 * @code
ganlikun 0:13413ea9a877 32 * // Toggle a LED
ganlikun 0:13413ea9a877 33 * #include "mbed.h"
ganlikun 0:13413ea9a877 34 *
ganlikun 0:13413ea9a877 35 * DigitalOut led(LED1);
ganlikun 0:13413ea9a877 36 *
ganlikun 0:13413ea9a877 37 * int main() {
ganlikun 0:13413ea9a877 38 * while(1) {
ganlikun 0:13413ea9a877 39 * led = !led;
ganlikun 0:13413ea9a877 40 * wait(0.2);
ganlikun 0:13413ea9a877 41 * }
ganlikun 0:13413ea9a877 42 * }
ganlikun 0:13413ea9a877 43 * @endcode
ganlikun 0:13413ea9a877 44 * @ingroup drivers
ganlikun 0:13413ea9a877 45 */
ganlikun 0:13413ea9a877 46 class DigitalOut {
ganlikun 0:13413ea9a877 47
ganlikun 0:13413ea9a877 48 public:
ganlikun 0:13413ea9a877 49 /** Create a DigitalOut connected to the specified pin
ganlikun 0:13413ea9a877 50 *
ganlikun 0:13413ea9a877 51 * @param pin DigitalOut pin to connect to
ganlikun 0:13413ea9a877 52 */
ganlikun 0:13413ea9a877 53 DigitalOut(PinName pin) : gpio() {
ganlikun 0:13413ea9a877 54 // No lock needed in the constructor
ganlikun 0:13413ea9a877 55 gpio_init_out(&gpio, pin);
ganlikun 0:13413ea9a877 56 }
ganlikun 0:13413ea9a877 57
ganlikun 0:13413ea9a877 58 /** Create a DigitalOut connected to the specified pin
ganlikun 0:13413ea9a877 59 *
ganlikun 0:13413ea9a877 60 * @param pin DigitalOut pin to connect to
ganlikun 0:13413ea9a877 61 * @param value the initial pin value
ganlikun 0:13413ea9a877 62 */
ganlikun 0:13413ea9a877 63 DigitalOut(PinName pin, int value) : gpio() {
ganlikun 0:13413ea9a877 64 // No lock needed in the constructor
ganlikun 0:13413ea9a877 65 gpio_init_out_ex(&gpio, pin, value);
ganlikun 0:13413ea9a877 66 }
ganlikun 0:13413ea9a877 67
ganlikun 0:13413ea9a877 68 /** Set the output, specified as 0 or 1 (int)
ganlikun 0:13413ea9a877 69 *
ganlikun 0:13413ea9a877 70 * @param value An integer specifying the pin output value,
ganlikun 0:13413ea9a877 71 * 0 for logical 0, 1 (or any other non-zero value) for logical 1
ganlikun 0:13413ea9a877 72 */
ganlikun 0:13413ea9a877 73 void write(int value) {
ganlikun 0:13413ea9a877 74 // Thread safe / atomic HAL call
ganlikun 0:13413ea9a877 75 gpio_write(&gpio, value);
ganlikun 0:13413ea9a877 76 }
ganlikun 0:13413ea9a877 77
ganlikun 0:13413ea9a877 78 /** Return the output setting, represented as 0 or 1 (int)
ganlikun 0:13413ea9a877 79 *
ganlikun 0:13413ea9a877 80 * @returns
ganlikun 0:13413ea9a877 81 * an integer representing the output setting of the pin,
ganlikun 0:13413ea9a877 82 * 0 for logical 0, 1 for logical 1
ganlikun 0:13413ea9a877 83 */
ganlikun 0:13413ea9a877 84 int read() {
ganlikun 0:13413ea9a877 85 // Thread safe / atomic HAL call
ganlikun 0:13413ea9a877 86 return gpio_read(&gpio);
ganlikun 0:13413ea9a877 87 }
ganlikun 0:13413ea9a877 88
ganlikun 0:13413ea9a877 89 /** Return the output setting, represented as 0 or 1 (int)
ganlikun 0:13413ea9a877 90 *
ganlikun 0:13413ea9a877 91 * @returns
ganlikun 0:13413ea9a877 92 * Non zero value if pin is connected to uc GPIO
ganlikun 0:13413ea9a877 93 * 0 if gpio object was initialized with NC
ganlikun 0:13413ea9a877 94 */
ganlikun 0:13413ea9a877 95 int is_connected() {
ganlikun 0:13413ea9a877 96 // Thread safe / atomic HAL call
ganlikun 0:13413ea9a877 97 return gpio_is_connected(&gpio);
ganlikun 0:13413ea9a877 98 }
ganlikun 0:13413ea9a877 99
ganlikun 0:13413ea9a877 100 /** A shorthand for write()
ganlikun 0:13413ea9a877 101 * \sa DigitalOut::write()
ganlikun 0:13413ea9a877 102 */
ganlikun 0:13413ea9a877 103 DigitalOut& operator= (int value) {
ganlikun 0:13413ea9a877 104 // Underlying write is thread safe
ganlikun 0:13413ea9a877 105 write(value);
ganlikun 0:13413ea9a877 106 return *this;
ganlikun 0:13413ea9a877 107 }
ganlikun 0:13413ea9a877 108
ganlikun 0:13413ea9a877 109 /** A shorthand for write()
ganlikun 0:13413ea9a877 110 * \sa DigitalOut::write()
ganlikun 0:13413ea9a877 111 */
ganlikun 0:13413ea9a877 112 DigitalOut& operator= (DigitalOut& rhs) {
ganlikun 0:13413ea9a877 113 core_util_critical_section_enter();
ganlikun 0:13413ea9a877 114 write(rhs.read());
ganlikun 0:13413ea9a877 115 core_util_critical_section_exit();
ganlikun 0:13413ea9a877 116 return *this;
ganlikun 0:13413ea9a877 117 }
ganlikun 0:13413ea9a877 118
ganlikun 0:13413ea9a877 119 /** A shorthand for read()
ganlikun 0:13413ea9a877 120 * \sa DigitalOut::read()
ganlikun 0:13413ea9a877 121 */
ganlikun 0:13413ea9a877 122 operator int() {
ganlikun 0:13413ea9a877 123 // Underlying call is thread safe
ganlikun 0:13413ea9a877 124 return read();
ganlikun 0:13413ea9a877 125 }
ganlikun 0:13413ea9a877 126
ganlikun 0:13413ea9a877 127 protected:
ganlikun 0:13413ea9a877 128 gpio_t gpio;
ganlikun 0:13413ea9a877 129 };
ganlikun 0:13413ea9a877 130
ganlikun 0:13413ea9a877 131 } // namespace mbed
ganlikun 0:13413ea9a877 132
ganlikun 0:13413ea9a877 133 #endif
ganlikun 0:13413ea9a877 134
ganlikun 0:13413ea9a877 135