Tomo Yamanaka / mbed-dev

mbed library sources. Supersedes mbed-src. GR-PEACH runs on RAM.

Fork of mbed-dev by mbed official

api/PwmOut.h@103:493a29d2d4d7, 2016-03-30 (annotated)

Committer:
1050186
Date:
Wed Mar 30 11:41:25 2016 +0000
Revision:
103:493a29d2d4d7
Parent:
0:9b334a45a8ff 
GR-PEACH runs on RAM.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #ifndef MBED_PWMOUT_H
bogdanm 0:9b334a45a8ff 17 #define MBED_PWMOUT_H
bogdanm 0:9b334a45a8ff 18
bogdanm 0:9b334a45a8ff 19 #include "platform.h"
bogdanm 0:9b334a45a8ff 20
bogdanm 0:9b334a45a8ff 21 #if DEVICE_PWMOUT
bogdanm 0:9b334a45a8ff 22 #include "pwmout_api.h"
bogdanm 0:9b334a45a8ff 23
bogdanm 0:9b334a45a8ff 24 namespace mbed {
bogdanm 0:9b334a45a8ff 25
bogdanm 0:9b334a45a8ff 26 /** A pulse-width modulation digital output
bogdanm 0:9b334a45a8ff 27 *
bogdanm 0:9b334a45a8ff 28 * Example
bogdanm 0:9b334a45a8ff 29 * @code
bogdanm 0:9b334a45a8ff 30 * // Fade a led on.
bogdanm 0:9b334a45a8ff 31 * #include "mbed.h"
bogdanm 0:9b334a45a8ff 32 *
bogdanm 0:9b334a45a8ff 33 * PwmOut led(LED1);
bogdanm 0:9b334a45a8ff 34 *
bogdanm 0:9b334a45a8ff 35 * int main() {
bogdanm 0:9b334a45a8ff 36 * while(1) {
bogdanm 0:9b334a45a8ff 37 * led = led + 0.01;
bogdanm 0:9b334a45a8ff 38 * wait(0.2);
bogdanm 0:9b334a45a8ff 39 * if(led == 1.0) {
bogdanm 0:9b334a45a8ff 40 * led = 0;
bogdanm 0:9b334a45a8ff 41 * }
bogdanm 0:9b334a45a8ff 42 * }
bogdanm 0:9b334a45a8ff 43 * }
bogdanm 0:9b334a45a8ff 44 * @endcode
bogdanm 0:9b334a45a8ff 45 *
bogdanm 0:9b334a45a8ff 46 * @note
bogdanm 0:9b334a45a8ff 47 * On the LPC1768 and LPC2368, the PWMs all share the same
bogdanm 0:9b334a45a8ff 48 * period - if you change the period for one, you change it for all.
bogdanm 0:9b334a45a8ff 49 * Although routines that change the period maintain the duty cycle
bogdanm 0:9b334a45a8ff 50 * for its PWM, all other PWMs will require their duty cycle to be
bogdanm 0:9b334a45a8ff 51 * refreshed.
bogdanm 0:9b334a45a8ff 52 */
bogdanm 0:9b334a45a8ff 53 class PwmOut {
bogdanm 0:9b334a45a8ff 54
bogdanm 0:9b334a45a8ff 55 public:
bogdanm 0:9b334a45a8ff 56
bogdanm 0:9b334a45a8ff 57 /** Create a PwmOut connected to the specified pin
bogdanm 0:9b334a45a8ff 58 *
bogdanm 0:9b334a45a8ff 59 * @param pin PwmOut pin to connect to
bogdanm 0:9b334a45a8ff 60 */
bogdanm 0:9b334a45a8ff 61 PwmOut(PinName pin) {
bogdanm 0:9b334a45a8ff 62 pwmout_init(&_pwm, pin);
bogdanm 0:9b334a45a8ff 63 }
bogdanm 0:9b334a45a8ff 64
bogdanm 0:9b334a45a8ff 65 /** Set the ouput duty-cycle, specified as a percentage (float)
bogdanm 0:9b334a45a8ff 66 *
bogdanm 0:9b334a45a8ff 67 * @param value A floating-point value representing the output duty-cycle,
bogdanm 0:9b334a45a8ff 68 * specified as a percentage. The value should lie between
bogdanm 0:9b334a45a8ff 69 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
bogdanm 0:9b334a45a8ff 70 * Values outside this range will be saturated to 0.0f or 1.0f.
bogdanm 0:9b334a45a8ff 71 */
bogdanm 0:9b334a45a8ff 72 void write(float value) {
bogdanm 0:9b334a45a8ff 73 pwmout_write(&_pwm, value);
bogdanm 0:9b334a45a8ff 74 }
bogdanm 0:9b334a45a8ff 75
bogdanm 0:9b334a45a8ff 76 /** Return the current output duty-cycle setting, measured as a percentage (float)
bogdanm 0:9b334a45a8ff 77 *
bogdanm 0:9b334a45a8ff 78 * @returns
bogdanm 0:9b334a45a8ff 79 * A floating-point value representing the current duty-cycle being output on the pin,
bogdanm 0:9b334a45a8ff 80 * measured as a percentage. The returned value will lie between
bogdanm 0:9b334a45a8ff 81 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
bogdanm 0:9b334a45a8ff 82 *
bogdanm 0:9b334a45a8ff 83 * @note
bogdanm 0:9b334a45a8ff 84 * This value may not match exactly the value set by a previous <write>.
bogdanm 0:9b334a45a8ff 85 */
bogdanm 0:9b334a45a8ff 86 float read() {
bogdanm 0:9b334a45a8ff 87 return pwmout_read(&_pwm);
bogdanm 0:9b334a45a8ff 88 }
bogdanm 0:9b334a45a8ff 89
bogdanm 0:9b334a45a8ff 90 /** Set the PWM period, specified in seconds (float), keeping the duty cycle the same.
bogdanm 0:9b334a45a8ff 91 *
bogdanm 0:9b334a45a8ff 92 * @note
bogdanm 0:9b334a45a8ff 93 * The resolution is currently in microseconds; periods smaller than this
bogdanm 0:9b334a45a8ff 94 * will be set to zero.
bogdanm 0:9b334a45a8ff 95 */
bogdanm 0:9b334a45a8ff 96 void period(float seconds) {
bogdanm 0:9b334a45a8ff 97 pwmout_period(&_pwm, seconds);
bogdanm 0:9b334a45a8ff 98 }
bogdanm 0:9b334a45a8ff 99
bogdanm 0:9b334a45a8ff 100 /** Set the PWM period, specified in milli-seconds (int), keeping the duty cycle the same.
bogdanm 0:9b334a45a8ff 101 */
bogdanm 0:9b334a45a8ff 102 void period_ms(int ms) {
bogdanm 0:9b334a45a8ff 103 pwmout_period_ms(&_pwm, ms);
bogdanm 0:9b334a45a8ff 104 }
bogdanm 0:9b334a45a8ff 105
bogdanm 0:9b334a45a8ff 106 /** Set the PWM period, specified in micro-seconds (int), keeping the duty cycle the same.
bogdanm 0:9b334a45a8ff 107 */
bogdanm 0:9b334a45a8ff 108 void period_us(int us) {
bogdanm 0:9b334a45a8ff 109 pwmout_period_us(&_pwm, us);
bogdanm 0:9b334a45a8ff 110 }
bogdanm 0:9b334a45a8ff 111
bogdanm 0:9b334a45a8ff 112 /** Set the PWM pulsewidth, specified in seconds (float), keeping the period the same.
bogdanm 0:9b334a45a8ff 113 */
bogdanm 0:9b334a45a8ff 114 void pulsewidth(float seconds) {
bogdanm 0:9b334a45a8ff 115 pwmout_pulsewidth(&_pwm, seconds);
bogdanm 0:9b334a45a8ff 116 }
bogdanm 0:9b334a45a8ff 117
bogdanm 0:9b334a45a8ff 118 /** Set the PWM pulsewidth, specified in milli-seconds (int), keeping the period the same.
bogdanm 0:9b334a45a8ff 119 */
bogdanm 0:9b334a45a8ff 120 void pulsewidth_ms(int ms) {
bogdanm 0:9b334a45a8ff 121 pwmout_pulsewidth_ms(&_pwm, ms);
bogdanm 0:9b334a45a8ff 122 }
bogdanm 0:9b334a45a8ff 123
bogdanm 0:9b334a45a8ff 124 /** Set the PWM pulsewidth, specified in micro-seconds (int), keeping the period the same.
bogdanm 0:9b334a45a8ff 125 */
bogdanm 0:9b334a45a8ff 126 void pulsewidth_us(int us) {
bogdanm 0:9b334a45a8ff 127 pwmout_pulsewidth_us(&_pwm, us);
bogdanm 0:9b334a45a8ff 128 }
bogdanm 0:9b334a45a8ff 129
bogdanm 0:9b334a45a8ff 130 #ifdef MBED_OPERATORS
bogdanm 0:9b334a45a8ff 131 /** A operator shorthand for write()
bogdanm 0:9b334a45a8ff 132 */
bogdanm 0:9b334a45a8ff 133 PwmOut& operator= (float value) {
bogdanm 0:9b334a45a8ff 134 write(value);
bogdanm 0:9b334a45a8ff 135 return *this;
bogdanm 0:9b334a45a8ff 136 }
bogdanm 0:9b334a45a8ff 137
bogdanm 0:9b334a45a8ff 138 PwmOut& operator= (PwmOut& rhs) {
bogdanm 0:9b334a45a8ff 139 write(rhs.read());
bogdanm 0:9b334a45a8ff 140 return *this;
bogdanm 0:9b334a45a8ff 141 }
bogdanm 0:9b334a45a8ff 142
bogdanm 0:9b334a45a8ff 143 /** An operator shorthand for read()
bogdanm 0:9b334a45a8ff 144 */
bogdanm 0:9b334a45a8ff 145 operator float() {
bogdanm 0:9b334a45a8ff 146 return read();
bogdanm 0:9b334a45a8ff 147 }
bogdanm 0:9b334a45a8ff 148 #endif
bogdanm 0:9b334a45a8ff 149
bogdanm 0:9b334a45a8ff 150 protected:
bogdanm 0:9b334a45a8ff 151 pwmout_t _pwm;
bogdanm 0:9b334a45a8ff 152 };
bogdanm 0:9b334a45a8ff 153
bogdanm 0:9b334a45a8ff 154 } // namespace mbed
bogdanm 0:9b334a45a8ff 155
bogdanm 0:9b334a45a8ff 156 #endif
bogdanm 0:9b334a45a8ff 157
bogdanm 0:9b334a45a8ff 158 #endif