mbed official / mbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Dependents:   hello SerialTestv11 SerialTestv12 Sierpinski ... more

mbed 2

This is the mbed 2 library. If you'd like to learn about Mbed OS please see the mbed-os docs.

drivers/AnalogOut.h@160:5571c4ff569f, 2018-01-17 (annotated)

Committer:
Anna Bridge
Date:
Wed Jan 17 16:13:02 2018 +0000
Revision:
160:5571c4ff569f
Parent:
156:ff21514d8981
Child:
170:e95d10626187
mbed library. Release version 158

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 156:ff21514d8981 1 /* mbed Microcontroller Library
AnnaBridge 156:ff21514d8981 2 * Copyright (c) 2006-2013 ARM Limited
AnnaBridge 156:ff21514d8981 3 *
AnnaBridge 156:ff21514d8981 4 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 156:ff21514d8981 5 * you may not use this file except in compliance with the License.
AnnaBridge 156:ff21514d8981 6 * You may obtain a copy of the License at
AnnaBridge 156:ff21514d8981 7 *
AnnaBridge 156:ff21514d8981 8 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 156:ff21514d8981 9 *
AnnaBridge 156:ff21514d8981 10 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 156:ff21514d8981 11 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 156:ff21514d8981 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 156:ff21514d8981 13 * See the License for the specific language governing permissions and
AnnaBridge 156:ff21514d8981 14 * limitations under the License.
AnnaBridge 156:ff21514d8981 15 */
AnnaBridge 156:ff21514d8981 16 #ifndef MBED_ANALOGOUT_H
AnnaBridge 156:ff21514d8981 17 #define MBED_ANALOGOUT_H
AnnaBridge 156:ff21514d8981 18
AnnaBridge 156:ff21514d8981 19 #include "platform/platform.h"
AnnaBridge 156:ff21514d8981 20
AnnaBridge 156:ff21514d8981 21 #if defined (DEVICE_ANALOGOUT) || defined(DOXYGEN_ONLY)
AnnaBridge 156:ff21514d8981 22
AnnaBridge 156:ff21514d8981 23 #include "hal/analogout_api.h"
AnnaBridge 156:ff21514d8981 24 #include "platform/PlatformMutex.h"
AnnaBridge 156:ff21514d8981 25
AnnaBridge 156:ff21514d8981 26 namespace mbed {
AnnaBridge 156:ff21514d8981 27 /** \addtogroup drivers */
AnnaBridge 156:ff21514d8981 28
AnnaBridge 156:ff21514d8981 29 /** An analog output, used for setting the voltage on a pin
AnnaBridge 156:ff21514d8981 30 *
AnnaBridge 156:ff21514d8981 31 * @note Synchronization level: Thread safe
AnnaBridge 156:ff21514d8981 32 *
AnnaBridge 156:ff21514d8981 33 * Example:
AnnaBridge 156:ff21514d8981 34 * @code
AnnaBridge 156:ff21514d8981 35 * // Make a sawtooth output
AnnaBridge 156:ff21514d8981 36 *
AnnaBridge 156:ff21514d8981 37 * #include "mbed.h"
AnnaBridge 156:ff21514d8981 38 *
AnnaBridge 156:ff21514d8981 39 * AnalogOut tri(p18);
AnnaBridge 156:ff21514d8981 40 * int main() {
AnnaBridge 156:ff21514d8981 41 * while(1) {
AnnaBridge 156:ff21514d8981 42 * tri = tri + 0.01;
AnnaBridge 156:ff21514d8981 43 * wait_us(1);
AnnaBridge 156:ff21514d8981 44 * if(tri == 1) {
AnnaBridge 156:ff21514d8981 45 * tri = 0;
AnnaBridge 156:ff21514d8981 46 * }
AnnaBridge 156:ff21514d8981 47 * }
AnnaBridge 156:ff21514d8981 48 * }
AnnaBridge 156:ff21514d8981 49 * @endcode
AnnaBridge 156:ff21514d8981 50 * @ingroup drivers
AnnaBridge 156:ff21514d8981 51 */
AnnaBridge 156:ff21514d8981 52 class AnalogOut {
AnnaBridge 156:ff21514d8981 53
AnnaBridge 156:ff21514d8981 54 public:
AnnaBridge 156:ff21514d8981 55
AnnaBridge 156:ff21514d8981 56 /** Create an AnalogOut connected to the specified pin
AnnaBridge 156:ff21514d8981 57 *
AnnaBridge 156:ff21514d8981 58 * @param pin AnalogOut pin to connect to
AnnaBridge 156:ff21514d8981 59 */
AnnaBridge 156:ff21514d8981 60 AnalogOut(PinName pin) {
AnnaBridge 156:ff21514d8981 61 analogout_init(&_dac, pin);
AnnaBridge 156:ff21514d8981 62 }
AnnaBridge 156:ff21514d8981 63
AnnaBridge 156:ff21514d8981 64 /** Set the output voltage, specified as a percentage (float)
AnnaBridge 156:ff21514d8981 65 *
AnnaBridge 156:ff21514d8981 66 * @param value A floating-point value representing the output voltage,
AnnaBridge 156:ff21514d8981 67 * specified as a percentage. The value should lie between
AnnaBridge 156:ff21514d8981 68 * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).
AnnaBridge 156:ff21514d8981 69 * Values outside this range will be saturated to 0.0f or 1.0f.
AnnaBridge 156:ff21514d8981 70 */
AnnaBridge 156:ff21514d8981 71 void write(float value) {
AnnaBridge 156:ff21514d8981 72 lock();
AnnaBridge 156:ff21514d8981 73 analogout_write(&_dac, value);
AnnaBridge 156:ff21514d8981 74 unlock();
AnnaBridge 156:ff21514d8981 75 }
AnnaBridge 156:ff21514d8981 76
AnnaBridge 156:ff21514d8981 77 /** Set the output voltage, represented as an unsigned short in the range [0x0, 0xFFFF]
AnnaBridge 156:ff21514d8981 78 *
AnnaBridge 156:ff21514d8981 79 * @param value 16-bit unsigned short representing the output voltage,
AnnaBridge 156:ff21514d8981 80 * normalised to a 16-bit value (0x0000 = 0v, 0xFFFF = 3.3v)
AnnaBridge 156:ff21514d8981 81 */
AnnaBridge 156:ff21514d8981 82 void write_u16(unsigned short value) {
AnnaBridge 156:ff21514d8981 83 lock();
AnnaBridge 156:ff21514d8981 84 analogout_write_u16(&_dac, value);
AnnaBridge 156:ff21514d8981 85 unlock();
AnnaBridge 156:ff21514d8981 86 }
AnnaBridge 156:ff21514d8981 87
AnnaBridge 156:ff21514d8981 88 /** Return the current output voltage setting, measured as a percentage (float)
AnnaBridge 156:ff21514d8981 89 *
AnnaBridge 156:ff21514d8981 90 * @returns
AnnaBridge 156:ff21514d8981 91 * A floating-point value representing the current voltage being output on the pin,
AnnaBridge 156:ff21514d8981 92 * measured as a percentage. The returned value will lie between
AnnaBridge 156:ff21514d8981 93 * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).
AnnaBridge 156:ff21514d8981 94 *
AnnaBridge 156:ff21514d8981 95 * @note
AnnaBridge 156:ff21514d8981 96 * This value may not match exactly the value set by a previous write().
AnnaBridge 156:ff21514d8981 97 */
AnnaBridge 156:ff21514d8981 98 float read() {
AnnaBridge 156:ff21514d8981 99 lock();
AnnaBridge 156:ff21514d8981 100 float ret = analogout_read(&_dac);
AnnaBridge 156:ff21514d8981 101 unlock();
AnnaBridge 156:ff21514d8981 102 return ret;
AnnaBridge 156:ff21514d8981 103 }
AnnaBridge 156:ff21514d8981 104
AnnaBridge 156:ff21514d8981 105 /** An operator shorthand for write()
AnnaBridge 156:ff21514d8981 106 * \sa AnalogOut::write()
AnnaBridge 156:ff21514d8981 107 */
AnnaBridge 156:ff21514d8981 108 AnalogOut& operator= (float percent) {
AnnaBridge 156:ff21514d8981 109 // Underlying write call is thread safe
AnnaBridge 156:ff21514d8981 110 write(percent);
AnnaBridge 156:ff21514d8981 111 return *this;
AnnaBridge 156:ff21514d8981 112 }
AnnaBridge 156:ff21514d8981 113
AnnaBridge 156:ff21514d8981 114 /** An operator shorthand for write()
AnnaBridge 156:ff21514d8981 115 * \sa AnalogOut::write()
AnnaBridge 156:ff21514d8981 116 */
AnnaBridge 156:ff21514d8981 117 AnalogOut& operator= (AnalogOut& rhs) {
AnnaBridge 156:ff21514d8981 118 // Underlying write call is thread safe
AnnaBridge 156:ff21514d8981 119 write(rhs.read());
AnnaBridge 156:ff21514d8981 120 return *this;
AnnaBridge 156:ff21514d8981 121 }
AnnaBridge 156:ff21514d8981 122
AnnaBridge 156:ff21514d8981 123 /** An operator shorthand for read()
AnnaBridge 156:ff21514d8981 124 * \sa AnalogOut::read()
AnnaBridge 156:ff21514d8981 125 */
AnnaBridge 156:ff21514d8981 126 operator float() {
AnnaBridge 156:ff21514d8981 127 // Underlying read call is thread safe
AnnaBridge 156:ff21514d8981 128 return read();
AnnaBridge 156:ff21514d8981 129 }
AnnaBridge 156:ff21514d8981 130
AnnaBridge 156:ff21514d8981 131 virtual ~AnalogOut() {
AnnaBridge 156:ff21514d8981 132 // Do nothing
AnnaBridge 156:ff21514d8981 133 }
AnnaBridge 156:ff21514d8981 134
AnnaBridge 156:ff21514d8981 135 protected:
AnnaBridge 156:ff21514d8981 136
AnnaBridge 156:ff21514d8981 137 virtual void lock() {
AnnaBridge 156:ff21514d8981 138 _mutex.lock();
AnnaBridge 156:ff21514d8981 139 }
AnnaBridge 156:ff21514d8981 140
AnnaBridge 156:ff21514d8981 141 virtual void unlock() {
AnnaBridge 156:ff21514d8981 142 _mutex.unlock();
AnnaBridge 156:ff21514d8981 143 }
AnnaBridge 156:ff21514d8981 144
AnnaBridge 156:ff21514d8981 145 dac_t _dac;
AnnaBridge 156:ff21514d8981 146 PlatformMutex _mutex;
AnnaBridge 156:ff21514d8981 147 };
AnnaBridge 156:ff21514d8981 148
AnnaBridge 156:ff21514d8981 149 } // namespace mbed
AnnaBridge 156:ff21514d8981 150
AnnaBridge 156:ff21514d8981 151 #endif
AnnaBridge 156:ff21514d8981 152
AnnaBridge 156:ff21514d8981 153 #endif