Tyler Weaver / Servo

Added max and min calibration

Dependents:   HARP_simple HARP HARP_localFileSystemTest Servo_Calibration_Test ... more

Fork of Servo by Simon Ford

Servo.cpp@4:1e75dcbded83, 2012-09-20 (annotated)

Committer:
tylerjw
Date:
Thu Sep 20 23:49:47 2012 +0000
Revision:
4:1e75dcbded83
Parent:
2:8995c167f399 
0.1

;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
tylerjw 4:1e75dcbded83 1 /* mbed R/C Servo Library
tylerjw 4:1e75dcbded83 2 *
tylerjw 4:1e75dcbded83 3 * Copyright (c) 2007-2010 sford, cstyles
tylerjw 4:1e75dcbded83 4 *
tylerjw 4:1e75dcbded83 5 * Permission is hereby granted, free of charge, to any person obtaining a copy
tylerjw 4:1e75dcbded83 6 * of this software and associated documentation files (the "Software"), to deal
tylerjw 4:1e75dcbded83 7 * in the Software without restriction, including without limitation the rights
tylerjw 4:1e75dcbded83 8 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
tylerjw 4:1e75dcbded83 9 * copies of the Software, and to permit persons to whom the Software is
tylerjw 4:1e75dcbded83 10 * furnished to do so, subject to the following conditions:
tylerjw 4:1e75dcbded83 11 *
tylerjw 4:1e75dcbded83 12 * The above copyright notice and this permission notice shall be included in
tylerjw 4:1e75dcbded83 13 * all copies or substantial portions of the Software.
tylerjw 4:1e75dcbded83 14 *
tylerjw 4:1e75dcbded83 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
tylerjw 4:1e75dcbded83 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
tylerjw 4:1e75dcbded83 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
tylerjw 4:1e75dcbded83 18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
tylerjw 4:1e75dcbded83 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
tylerjw 4:1e75dcbded83 20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
tylerjw 4:1e75dcbded83 21 * THE SOFTWARE.
tylerjw 4:1e75dcbded83 22 */
tylerjw 4:1e75dcbded83 23
tylerjw 4:1e75dcbded83 24 #include "Servo.h"
tylerjw 4:1e75dcbded83 25 #include "mbed.h"
tylerjw 4:1e75dcbded83 26
tylerjw 4:1e75dcbded83 27 static float clamp(float value, float min, float max) {
tylerjw 4:1e75dcbded83 28 if(value < min) {
tylerjw 4:1e75dcbded83 29 return min;
tylerjw 4:1e75dcbded83 30 } else if(value > max) {
tylerjw 4:1e75dcbded83 31 return max;
tylerjw 4:1e75dcbded83 32 } else {
tylerjw 4:1e75dcbded83 33 return value;
tylerjw 4:1e75dcbded83 34 }
tylerjw 4:1e75dcbded83 35 }
tylerjw 4:1e75dcbded83 36
tylerjw 4:1e75dcbded83 37 Servo::Servo(PinName pin) : _pwm(pin) {
tylerjw 4:1e75dcbded83 38 calibrate();
tylerjw 4:1e75dcbded83 39 write(0.5);
tylerjw 4:1e75dcbded83 40 }
tylerjw 4:1e75dcbded83 41
tylerjw 4:1e75dcbded83 42 void Servo::write(float percent) {
tylerjw 4:1e75dcbded83 43 float offset = _range * 2.0 * (percent - 0.5);
tylerjw 4:1e75dcbded83 44 _pwm.pulsewidth(0.0015 + clamp(offset, _range_min, _range_max));
tylerjw 4:1e75dcbded83 45 _p = clamp(percent, 0.0, 1.0);
tylerjw 4:1e75dcbded83 46 }
tylerjw 4:1e75dcbded83 47
tylerjw 4:1e75dcbded83 48 void Servo::position(float degrees) {
tylerjw 4:1e75dcbded83 49 float offset = _range * (degrees / _degrees);
tylerjw 4:1e75dcbded83 50 _pwm.pulsewidth(0.0015 + clamp(offset, _range_min, _range_max));
tylerjw 4:1e75dcbded83 51 }
tylerjw 4:1e75dcbded83 52
tylerjw 4:1e75dcbded83 53 void Servo::calibrate(float range, float degrees) {
tylerjw 4:1e75dcbded83 54 _range_max = range;
tylerjw 4:1e75dcbded83 55 _range_min = -range;
tylerjw 4:1e75dcbded83 56 _range = (_range_max + -_range_min) / 2.0;
tylerjw 4:1e75dcbded83 57 _degrees = degrees;
tylerjw 4:1e75dcbded83 58 }
tylerjw 4:1e75dcbded83 59
tylerjw 4:1e75dcbded83 60 void Servo::calibrate_min(float min, float degrees) {
tylerjw 4:1e75dcbded83 61 _range_min = min;
tylerjw 4:1e75dcbded83 62 _range = (_range_max + -_range_min) / 2.0;
tylerjw 4:1e75dcbded83 63 _degrees = degrees;
tylerjw 4:1e75dcbded83 64 }
tylerjw 4:1e75dcbded83 65
tylerjw 4:1e75dcbded83 66 void Servo::calibrate_max(float max, float degrees) {
tylerjw 4:1e75dcbded83 67 _range_max = max;
tylerjw 4:1e75dcbded83 68 _range = (_range_max + -_range_min) / 2.0;
tylerjw 4:1e75dcbded83 69 _degrees = degrees;
tylerjw 4:1e75dcbded83 70 }
tylerjw 4:1e75dcbded83 71
tylerjw 4:1e75dcbded83 72 float Servo::read() {
tylerjw 4:1e75dcbded83 73 return _p;
tylerjw 4:1e75dcbded83 74 }
tylerjw 4:1e75dcbded83 75
tylerjw 4:1e75dcbded83 76 Servo& Servo::operator= (float percent) {
tylerjw 4:1e75dcbded83 77 write(percent);
tylerjw 4:1e75dcbded83 78 return *this;
tylerjw 4:1e75dcbded83 79 }
tylerjw 4:1e75dcbded83 80
tylerjw 4:1e75dcbded83 81 Servo& Servo::operator= (Servo& rhs) {
tylerjw 4:1e75dcbded83 82 write(rhs.read());
tylerjw 4:1e75dcbded83 83 return *this;
tylerjw 4:1e75dcbded83 84 }
tylerjw 4:1e75dcbded83 85
tylerjw 4:1e75dcbded83 86 Servo::operator float() {
tylerjw 4:1e75dcbded83 87 return read();
tylerjw 4:1e75dcbded83 88 }