Servo control routines
Fork of Servo by
Servo.cpp@0:b3bed6121155, 2016-05-30 (annotated)
- Committer:
- Decimus
- Date:
- Mon May 30 08:09:19 2016 +0000
- Revision:
- 0:b3bed6121155
[+]
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
Decimus | 0:b3bed6121155 | 1 | /* mbed R/C Servo Library |
Decimus | 0:b3bed6121155 | 2 | * |
Decimus | 0:b3bed6121155 | 3 | * Copyright (c) 2007-2010 sford, cstyles |
Decimus | 0:b3bed6121155 | 4 | * |
Decimus | 0:b3bed6121155 | 5 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
Decimus | 0:b3bed6121155 | 6 | * of this software and associated documentation files (the "Software"), to deal |
Decimus | 0:b3bed6121155 | 7 | * in the Software without restriction, including without limitation the rights |
Decimus | 0:b3bed6121155 | 8 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
Decimus | 0:b3bed6121155 | 9 | * copies of the Software, and to permit persons to whom the Software is |
Decimus | 0:b3bed6121155 | 10 | * furnished to do so, subject to the following conditions: |
Decimus | 0:b3bed6121155 | 11 | * |
Decimus | 0:b3bed6121155 | 12 | * The above copyright notice and this permission notice shall be included in |
Decimus | 0:b3bed6121155 | 13 | * all copies or substantial portions of the Software. |
Decimus | 0:b3bed6121155 | 14 | * |
Decimus | 0:b3bed6121155 | 15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
Decimus | 0:b3bed6121155 | 16 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
Decimus | 0:b3bed6121155 | 17 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
Decimus | 0:b3bed6121155 | 18 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
Decimus | 0:b3bed6121155 | 19 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
Decimus | 0:b3bed6121155 | 20 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
Decimus | 0:b3bed6121155 | 21 | * THE SOFTWARE. |
Decimus | 0:b3bed6121155 | 22 | */ |
Decimus | 0:b3bed6121155 | 23 | |
Decimus | 0:b3bed6121155 | 24 | #include "Servo.h" |
Decimus | 0:b3bed6121155 | 25 | #include "mbed.h" |
Decimus | 0:b3bed6121155 | 26 | |
Decimus | 0:b3bed6121155 | 27 | static float clamp(float value, float min, float max) { |
Decimus | 0:b3bed6121155 | 28 | if(value < min) { |
Decimus | 0:b3bed6121155 | 29 | return min; |
Decimus | 0:b3bed6121155 | 30 | } else if(value > max) { |
Decimus | 0:b3bed6121155 | 31 | return max; |
Decimus | 0:b3bed6121155 | 32 | } else { |
Decimus | 0:b3bed6121155 | 33 | return value; |
Decimus | 0:b3bed6121155 | 34 | } |
Decimus | 0:b3bed6121155 | 35 | } |
Decimus | 0:b3bed6121155 | 36 | |
Decimus | 0:b3bed6121155 | 37 | Servo::Servo(PinName pin) : _pwm(pin) { |
Decimus | 0:b3bed6121155 | 38 | //calibrate(); |
Decimus | 0:b3bed6121155 | 39 | //write(0.5); |
Decimus | 0:b3bed6121155 | 40 | } |
Decimus | 0:b3bed6121155 | 41 | |
Decimus | 0:b3bed6121155 | 42 | void Servo::write(float percent) { |
Decimus | 0:b3bed6121155 | 43 | float offset = _range * 2.0 * (percent - 0.5); |
Decimus | 0:b3bed6121155 | 44 | _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range)); |
Decimus | 0:b3bed6121155 | 45 | _p = clamp(percent, 0.0, 1.0); |
Decimus | 0:b3bed6121155 | 46 | } |
Decimus | 0:b3bed6121155 | 47 | |
Decimus | 0:b3bed6121155 | 48 | void Servo::position(float degrees) { |
Decimus | 0:b3bed6121155 | 49 | float offset = _range * (degrees / _degrees); |
Decimus | 0:b3bed6121155 | 50 | _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range)); |
Decimus | 0:b3bed6121155 | 51 | } |
Decimus | 0:b3bed6121155 | 52 | |
Decimus | 0:b3bed6121155 | 53 | void Servo::calibrate(float range, float degrees, float period) { |
Decimus | 0:b3bed6121155 | 54 | _range = range; |
Decimus | 0:b3bed6121155 | 55 | _degrees = degrees; |
Decimus | 0:b3bed6121155 | 56 | _pwm.period(period); |
Decimus | 0:b3bed6121155 | 57 | } |
Decimus | 0:b3bed6121155 | 58 | |
Decimus | 0:b3bed6121155 | 59 | float Servo::read() { |
Decimus | 0:b3bed6121155 | 60 | return _p; |
Decimus | 0:b3bed6121155 | 61 | } |
Decimus | 0:b3bed6121155 | 62 | |
Decimus | 0:b3bed6121155 | 63 | Servo& Servo::operator= (float percent) { |
Decimus | 0:b3bed6121155 | 64 | write(percent); |
Decimus | 0:b3bed6121155 | 65 | return *this; |
Decimus | 0:b3bed6121155 | 66 | } |
Decimus | 0:b3bed6121155 | 67 | |
Decimus | 0:b3bed6121155 | 68 | Servo& Servo::operator= (Servo& rhs) { |
Decimus | 0:b3bed6121155 | 69 | write(rhs.read()); |
Decimus | 0:b3bed6121155 | 70 | return *this; |
Decimus | 0:b3bed6121155 | 71 | } |
Decimus | 0:b3bed6121155 | 72 | |
Decimus | 0:b3bed6121155 | 73 | Servo::operator float() { |
Decimus | 0:b3bed6121155 | 74 | return read(); |
Decimus | 0:b3bed6121155 | 75 | } |