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api/PwmOut.h@13:0645d8841f51, 2013-08-05 (annotated)

Committer:
bogdanm
Date:
Mon Aug 05 14:12:34 2013 +0300
Revision:
13:0645d8841f51
Parent:
10:3bc89ef62ce7 
Update mbed sources to revision 64

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bogdanm 13:0645d8841f51 1 /* mbed Microcontroller Library
bogdanm 13:0645d8841f51 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 13:0645d8841f51 3 *
bogdanm 13:0645d8841f51 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 13:0645d8841f51 5 * you may not use this file except in compliance with the License.
bogdanm 13:0645d8841f51 6 * You may obtain a copy of the License at
bogdanm 13:0645d8841f51 7 *
bogdanm 13:0645d8841f51 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 13:0645d8841f51 9 *
bogdanm 13:0645d8841f51 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 13:0645d8841f51 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 13:0645d8841f51 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 13:0645d8841f51 13 * See the License for the specific language governing permissions and
bogdanm 13:0645d8841f51 14 * limitations under the License.
bogdanm 13:0645d8841f51 15 */
bogdanm 13:0645d8841f51 16 #ifndef MBED_PWMOUT_H
bogdanm 13:0645d8841f51 17 #define MBED_PWMOUT_H
bogdanm 13:0645d8841f51 18
bogdanm 13:0645d8841f51 19 #include "platform.h"
bogdanm 13:0645d8841f51 20
bogdanm 13:0645d8841f51 21 #if DEVICE_PWMOUT
bogdanm 13:0645d8841f51 22 #include "pwmout_api.h"
bogdanm 13:0645d8841f51 23
bogdanm 13:0645d8841f51 24 namespace mbed {
bogdanm 13:0645d8841f51 25
bogdanm 13:0645d8841f51 26 /** A pulse-width modulation digital output
bogdanm 13:0645d8841f51 27 *
bogdanm 13:0645d8841f51 28 * Example
bogdanm 13:0645d8841f51 29 * @code
bogdanm 13:0645d8841f51 30 * // Fade a led on.
bogdanm 13:0645d8841f51 31 * #include "mbed.h"
bogdanm 13:0645d8841f51 32 *
bogdanm 13:0645d8841f51 33 * PwmOut led(LED1);
bogdanm 13:0645d8841f51 34 *
bogdanm 13:0645d8841f51 35 * int main() {
bogdanm 13:0645d8841f51 36 * while(1) {
bogdanm 13:0645d8841f51 37 * led = led + 0.01;
bogdanm 13:0645d8841f51 38 * wait(0.2);
bogdanm 13:0645d8841f51 39 * if(led == 1.0) {
bogdanm 13:0645d8841f51 40 * led = 0;
bogdanm 13:0645d8841f51 41 * }
bogdanm 13:0645d8841f51 42 * }
bogdanm 13:0645d8841f51 43 * }
bogdanm 13:0645d8841f51 44 * @endcode
bogdanm 13:0645d8841f51 45 *
bogdanm 13:0645d8841f51 46 * @note
bogdanm 13:0645d8841f51 47 * On the LPC1768 and LPC2368, the PWMs all share the same
bogdanm 13:0645d8841f51 48 * period - if you change the period for one, you change it for all.
bogdanm 13:0645d8841f51 49 * Although routines that change the period maintain the duty cycle
bogdanm 13:0645d8841f51 50 * for its PWM, all other PWMs will require their duty cycle to be
bogdanm 13:0645d8841f51 51 * refreshed.
bogdanm 13:0645d8841f51 52 */
bogdanm 13:0645d8841f51 53 class PwmOut {
bogdanm 13:0645d8841f51 54
bogdanm 13:0645d8841f51 55 public:
bogdanm 13:0645d8841f51 56
bogdanm 13:0645d8841f51 57 /** Create a PwmOut connected to the specified pin
bogdanm 13:0645d8841f51 58 *
bogdanm 13:0645d8841f51 59 * @param pin PwmOut pin to connect to
bogdanm 13:0645d8841f51 60 */
bogdanm 13:0645d8841f51 61 PwmOut(PinName pin) {
bogdanm 13:0645d8841f51 62 pwmout_init(&_pwm, pin);
bogdanm 13:0645d8841f51 63 }
bogdanm 13:0645d8841f51 64
bogdanm 13:0645d8841f51 65 /** Set the ouput duty-cycle, specified as a percentage (float)
bogdanm 13:0645d8841f51 66 *
bogdanm 13:0645d8841f51 67 * @param value A floating-point value representing the output duty-cycle,
bogdanm 13:0645d8841f51 68 * specified as a percentage. The value should lie between
bogdanm 13:0645d8841f51 69 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
bogdanm 13:0645d8841f51 70 * Values outside this range will be saturated to 0.0f or 1.0f.
bogdanm 13:0645d8841f51 71 */
bogdanm 13:0645d8841f51 72 void write(float value) {
bogdanm 13:0645d8841f51 73 pwmout_write(&_pwm, value);
bogdanm 13:0645d8841f51 74 }
bogdanm 13:0645d8841f51 75
bogdanm 13:0645d8841f51 76 /** Return the current output duty-cycle setting, measured as a percentage (float)
bogdanm 13:0645d8841f51 77 *
bogdanm 13:0645d8841f51 78 * @returns
bogdanm 13:0645d8841f51 79 * A floating-point value representing the current duty-cycle being output on the pin,
bogdanm 13:0645d8841f51 80 * measured as a percentage. The returned value will lie between
bogdanm 13:0645d8841f51 81 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
bogdanm 13:0645d8841f51 82 *
bogdanm 13:0645d8841f51 83 * @note
bogdanm 13:0645d8841f51 84 * This value may not match exactly the value set by a previous <write>.
bogdanm 13:0645d8841f51 85 */
bogdanm 13:0645d8841f51 86 float read() {
bogdanm 13:0645d8841f51 87 return pwmout_read(&_pwm);
bogdanm 13:0645d8841f51 88 }
bogdanm 13:0645d8841f51 89
bogdanm 13:0645d8841f51 90 /** Set the PWM period, specified in seconds (float), keeping the duty cycle the same.
bogdanm 13:0645d8841f51 91 *
bogdanm 13:0645d8841f51 92 * @note
bogdanm 13:0645d8841f51 93 * The resolution is currently in microseconds; periods smaller than this
bogdanm 13:0645d8841f51 94 * will be set to zero.
bogdanm 13:0645d8841f51 95 */
bogdanm 13:0645d8841f51 96 void period(float seconds) {
bogdanm 13:0645d8841f51 97 pwmout_period(&_pwm, seconds);
bogdanm 13:0645d8841f51 98 }
bogdanm 13:0645d8841f51 99
bogdanm 13:0645d8841f51 100 /** Set the PWM period, specified in milli-seconds (int), keeping the duty cycle the same.
bogdanm 13:0645d8841f51 101 */
bogdanm 13:0645d8841f51 102 void period_ms(int ms) {
bogdanm 13:0645d8841f51 103 pwmout_period_ms(&_pwm, ms);
bogdanm 13:0645d8841f51 104 }
bogdanm 13:0645d8841f51 105
bogdanm 13:0645d8841f51 106 /** Set the PWM period, specified in micro-seconds (int), keeping the duty cycle the same.
bogdanm 13:0645d8841f51 107 */
bogdanm 13:0645d8841f51 108 void period_us(int us) {
bogdanm 13:0645d8841f51 109 pwmout_period_us(&_pwm, us);
bogdanm 13:0645d8841f51 110 }
bogdanm 13:0645d8841f51 111
bogdanm 13:0645d8841f51 112 /** Set the PWM pulsewidth, specified in seconds (float), keeping the period the same.
bogdanm 13:0645d8841f51 113 */
bogdanm 13:0645d8841f51 114 void pulsewidth(float seconds) {
bogdanm 13:0645d8841f51 115 pwmout_pulsewidth(&_pwm, seconds);
bogdanm 13:0645d8841f51 116 }
bogdanm 13:0645d8841f51 117
bogdanm 13:0645d8841f51 118 /** Set the PWM pulsewidth, specified in milli-seconds (int), keeping the period the same.
bogdanm 13:0645d8841f51 119 */
bogdanm 13:0645d8841f51 120 void pulsewidth_ms(int ms) {
bogdanm 13:0645d8841f51 121 pwmout_pulsewidth_ms(&_pwm, ms);
bogdanm 13:0645d8841f51 122 }
bogdanm 13:0645d8841f51 123
bogdanm 13:0645d8841f51 124 /** Set the PWM pulsewidth, specified in micro-seconds (int), keeping the period the same.
bogdanm 13:0645d8841f51 125 */
bogdanm 13:0645d8841f51 126 void pulsewidth_us(int us) {
bogdanm 13:0645d8841f51 127 pwmout_pulsewidth_us(&_pwm, us);
bogdanm 13:0645d8841f51 128 }
bogdanm 13:0645d8841f51 129
bogdanm 13:0645d8841f51 130 #ifdef MBED_OPERATORS
bogdanm 13:0645d8841f51 131 /** A operator shorthand for write()
bogdanm 13:0645d8841f51 132 */
bogdanm 13:0645d8841f51 133 PwmOut& operator= (float value) {
bogdanm 13:0645d8841f51 134 write(value);
bogdanm 13:0645d8841f51 135 return *this;
bogdanm 13:0645d8841f51 136 }
bogdanm 13:0645d8841f51 137
bogdanm 13:0645d8841f51 138 PwmOut& operator= (PwmOut& rhs) {
bogdanm 13:0645d8841f51 139 write(rhs.read());
bogdanm 13:0645d8841f51 140 return *this;
bogdanm 13:0645d8841f51 141 }
bogdanm 13:0645d8841f51 142
bogdanm 13:0645d8841f51 143 /** An operator shorthand for read()
bogdanm 13:0645d8841f51 144 */
bogdanm 13:0645d8841f51 145 operator float() {
bogdanm 13:0645d8841f51 146 return read();
bogdanm 13:0645d8841f51 147 }
bogdanm 13:0645d8841f51 148 #endif
bogdanm 13:0645d8841f51 149
bogdanm 13:0645d8841f51 150 protected:
bogdanm 13:0645d8841f51 151 pwmout_t _pwm;
bogdanm 13:0645d8841f51 152 };
bogdanm 13:0645d8841f51 153
bogdanm 13:0645d8841f51 154 } // namespace mbed
bogdanm 13:0645d8841f51 155
bogdanm 13:0645d8841f51 156 #endif
bogdanm 13:0645d8841f51 157
bogdanm 13:0645d8841f51 158 #endif