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Dependencies:   mbed-rtos mbed

Sensor/RotaryEncorder/RotaryEncoder.cpp@0:2a15bd367891, 2015-09-07 (annotated)

Committer:
shimogamo
Date:
Mon Sep 07 01:19:55 2015 +0000
Revision:
0:2a15bd367891
main?????

Who changed what in which revision?

UserRevisionLine numberNew contents of line
shimogamo 0:2a15bd367891 1
shimogamo 0:2a15bd367891 2
shimogamo 0:2a15bd367891 3
shimogamo 0:2a15bd367891 4
shimogamo 0:2a15bd367891 5
shimogamo 0:2a15bd367891 6 //ライブラリQEIの改造、
shimogamo 0:2a15bd367891 7 //改造点
shimogamo 0:2a15bd367891 8 //pulse1つでも対応できるように
shimogamo 0:2a15bd367891 9 //indexがなくてもrevolutionsを計算して出すように
shimogamo 0:2a15bd367891 10 //floatのrevolutionsもついでに実装
shimogamo 0:2a15bd367891 11
shimogamo 0:2a15bd367891 12
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shimogamo 0:2a15bd367891 22
shimogamo 0:2a15bd367891 23
shimogamo 0:2a15bd367891 24
shimogamo 0:2a15bd367891 25 /**
shimogamo 0:2a15bd367891 26 * @author Aaron Berk
shimogamo 0:2a15bd367891 27 *
shimogamo 0:2a15bd367891 28 * @section LICENSE
shimogamo 0:2a15bd367891 29 *
shimogamo 0:2a15bd367891 30 * Copyright (c) 2010 ARM Limited
shimogamo 0:2a15bd367891 31 *
shimogamo 0:2a15bd367891 32 * Permission is hereby granted, free of charge, to any person obtaining a copy
shimogamo 0:2a15bd367891 33 * of this software and associated documentation files (the "Software"), to deal
shimogamo 0:2a15bd367891 34 * in the Software without restriction, including without limitation the rights
shimogamo 0:2a15bd367891 35 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
shimogamo 0:2a15bd367891 36 * copies of the Software, and to permit persons to whom the Software is
shimogamo 0:2a15bd367891 37 * furnished to do so, subject to the following conditions:
shimogamo 0:2a15bd367891 38 *
shimogamo 0:2a15bd367891 39 * The above copyright notice and this permission notice shall be included in
shimogamo 0:2a15bd367891 40 * all copies or substantial portions of the Software.
shimogamo 0:2a15bd367891 41 *
shimogamo 0:2a15bd367891 42 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
shimogamo 0:2a15bd367891 43 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
shimogamo 0:2a15bd367891 44 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
shimogamo 0:2a15bd367891 45 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
shimogamo 0:2a15bd367891 46 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
shimogamo 0:2a15bd367891 47 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
shimogamo 0:2a15bd367891 48 * THE SOFTWARE.
shimogamo 0:2a15bd367891 49 *
shimogamo 0:2a15bd367891 50 * @section DESCRIPTION
shimogamo 0:2a15bd367891 51 *
shimogamo 0:2a15bd367891 52 * Quadrature Encoder Interface.
shimogamo 0:2a15bd367891 53 *
shimogamo 0:2a15bd367891 54 * A quadrature encoder consists of two code tracks on a disc which are 90
shimogamo 0:2a15bd367891 55 * degrees out of phase. It can be used to determine how far a wheel has
shimogamo 0:2a15bd367891 56 * rotated, relative to a known starting position.
shimogamo 0:2a15bd367891 57 *
shimogamo 0:2a15bd367891 58 * Only one code track changes at a time leading to a more robust system than
shimogamo 0:2a15bd367891 59 * a single track, because any jitter around any edge won't cause a state
shimogamo 0:2a15bd367891 60 * change as the other track will remain constant.
shimogamo 0:2a15bd367891 61 *
shimogamo 0:2a15bd367891 62 * Encoders can be a homebrew affair, consisting of infrared emitters/receivers
shimogamo 0:2a15bd367891 63 * and paper code tracks consisting of alternating black and white sections;
shimogamo 0:2a15bd367891 64 * alternatively, complete disk and PCB emitter/receiver encoder systems can
shimogamo 0:2a15bd367891 65 * be bought, but the interface, regardless of implementation is the same.
shimogamo 0:2a15bd367891 66 *
shimogamo 0:2a15bd367891 67 * +-----+ +-----+ +-----+
shimogamo 0:2a15bd367891 68 * Channel A | ^ | | | | |
shimogamo 0:2a15bd367891 69 * ---+ ^ +-----+ +-----+ +-----
shimogamo 0:2a15bd367891 70 * ^ ^
shimogamo 0:2a15bd367891 71 * ^ +-----+ +-----+ +-----+
shimogamo 0:2a15bd367891 72 * Channel B ^ | | | | | |
shimogamo 0:2a15bd367891 73 * ------+ +-----+ +-----+ +-----
shimogamo 0:2a15bd367891 74 * ^ ^
shimogamo 0:2a15bd367891 75 * ^ ^
shimogamo 0:2a15bd367891 76 * 90deg
shimogamo 0:2a15bd367891 77 *
shimogamo 0:2a15bd367891 78 * The interface uses X2 encoding by default which calculates the pulse count
shimogamo 0:2a15bd367891 79 * based on reading the current state after each rising and falling edge of
shimogamo 0:2a15bd367891 80 * channel A.
shimogamo 0:2a15bd367891 81 *
shimogamo 0:2a15bd367891 82 * +-----+ +-----+ +-----+
shimogamo 0:2a15bd367891 83 * Channel A | | | | | |
shimogamo 0:2a15bd367891 84 * ---+ +-----+ +-----+ +-----
shimogamo 0:2a15bd367891 85 * ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 86 * ^ +-----+ ^ +-----+ ^ +-----+
shimogamo 0:2a15bd367891 87 * Channel B ^ | ^ | ^ | ^ | ^ | |
shimogamo 0:2a15bd367891 88 * ------+ ^ +-----+ ^ +-----+ +--
shimogamo 0:2a15bd367891 89 * ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 90 * ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 91 * Pulse count 0 1 2 3 4 5 ...
shimogamo 0:2a15bd367891 92 *
shimogamo 0:2a15bd367891 93 * This interface can also use X4 encoding which calculates the pulse count
shimogamo 0:2a15bd367891 94 * based on reading the current state after each rising and falling edge of
shimogamo 0:2a15bd367891 95 * either channel.
shimogamo 0:2a15bd367891 96 *
shimogamo 0:2a15bd367891 97 * +-----+ +-----+ +-----+
shimogamo 0:2a15bd367891 98 * Channel A | | | | | |
shimogamo 0:2a15bd367891 99 * ---+ +-----+ +-----+ +-----
shimogamo 0:2a15bd367891 100 * ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 101 * ^ +-----+ ^ +-----+ ^ +-----+
shimogamo 0:2a15bd367891 102 * Channel B ^ | ^ | ^ | ^ | ^ | |
shimogamo 0:2a15bd367891 103 * ------+ ^ +-----+ ^ +-----+ +--
shimogamo 0:2a15bd367891 104 * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 105 * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 106 * Pulse count 0 1 2 3 4 5 6 7 8 9 ...
shimogamo 0:2a15bd367891 107 *
shimogamo 0:2a15bd367891 108 * It defaults
shimogamo 0:2a15bd367891 109 *
shimogamo 0:2a15bd367891 110 * An optional index channel can be used which determines when a full
shimogamo 0:2a15bd367891 111 * revolution has occured.
shimogamo 0:2a15bd367891 112 *
shimogamo 0:2a15bd367891 113 * If a 4 pules per revolution encoder was used, with X4 encoding,
shimogamo 0:2a15bd367891 114 * the following would be observed.
shimogamo 0:2a15bd367891 115 *
shimogamo 0:2a15bd367891 116 * +-----+ +-----+ +-----+
shimogamo 0:2a15bd367891 117 * Channel A | | | | | |
shimogamo 0:2a15bd367891 118 * ---+ +-----+ +-----+ +-----
shimogamo 0:2a15bd367891 119 * ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 120 * ^ +-----+ ^ +-----+ ^ +-----+
shimogamo 0:2a15bd367891 121 * Channel B ^ | ^ | ^ | ^ | ^ | |
shimogamo 0:2a15bd367891 122 * ------+ ^ +-----+ ^ +-----+ +--
shimogamo 0:2a15bd367891 123 * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 124 * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 125 * ^ ^ ^ +--+ ^ ^ +--+ ^
shimogamo 0:2a15bd367891 126 * ^ ^ ^ | | ^ ^ | | ^
shimogamo 0:2a15bd367891 127 * Index ------------+ +--------+ +-----------
shimogamo 0:2a15bd367891 128 * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^
shimogamo 0:2a15bd367891 129 * Pulse count 0 1 2 3 4 5 6 7 8 9 ...
shimogamo 0:2a15bd367891 130 * Rev. count 0 1 2
shimogamo 0:2a15bd367891 131 *
shimogamo 0:2a15bd367891 132 * Rotational position in degrees can be calculated by:
shimogamo 0:2a15bd367891 133 *
shimogamo 0:2a15bd367891 134 * (pulse count / X * N) * 360
shimogamo 0:2a15bd367891 135 *
shimogamo 0:2a15bd367891 136 * Where X is the encoding type [e.g. X4 encoding => X=4], and N is the number
shimogamo 0:2a15bd367891 137 * of pulses per revolution.
shimogamo 0:2a15bd367891 138 *
shimogamo 0:2a15bd367891 139 * Linear position can be calculated by:
shimogamo 0:2a15bd367891 140 *
shimogamo 0:2a15bd367891 141 * (pulse count / X * N) * (1 / PPI)
shimogamo 0:2a15bd367891 142 *
shimogamo 0:2a15bd367891 143 * Where X is encoding type [e.g. X4 encoding => X=44], N is the number of
shimogamo 0:2a15bd367891 144 * pulses per revolution, and PPI is pulses per inch, or the equivalent for
shimogamo 0:2a15bd367891 145 * any other unit of displacement. PPI can be calculated by taking the
shimogamo 0:2a15bd367891 146 * circumference of the wheel or encoder disk and dividing it by the number
shimogamo 0:2a15bd367891 147 * of pulses per revolution.
shimogamo 0:2a15bd367891 148 */
shimogamo 0:2a15bd367891 149
shimogamo 0:2a15bd367891 150 /**
shimogamo 0:2a15bd367891 151 * Includes
shimogamo 0:2a15bd367891 152 */
shimogamo 0:2a15bd367891 153 #include "RotaryEncoder.h"
shimogamo 0:2a15bd367891 154
shimogamo 0:2a15bd367891 155 RotaryEncoder::RotaryEncoder(PinName channelA,
shimogamo 0:2a15bd367891 156 PinName channelB,
shimogamo 0:2a15bd367891 157 PinName index,
shimogamo 0:2a15bd367891 158 int pulsesPerRev,
shimogamo 0:2a15bd367891 159 Encoding encoding) : channelA_(channelA), channelB_(channelB),
shimogamo 0:2a15bd367891 160 index_(index) {
shimogamo 0:2a15bd367891 161
shimogamo 0:2a15bd367891 162 pulses_ = 0;
shimogamo 0:2a15bd367891 163 revolutions_ = 0;
shimogamo 0:2a15bd367891 164 pulsesPerRev_ = pulsesPerRev;
shimogamo 0:2a15bd367891 165 chanBisvalid_ = false;
shimogamo 0:2a15bd367891 166 indexisvalid_ = false;
shimogamo 0:2a15bd367891 167 if(channelB != NC){
shimogamo 0:2a15bd367891 168 encoding_ = encoding;
shimogamo 0:2a15bd367891 169 } else {
shimogamo 0:2a15bd367891 170 encoding_ = X2_ENCODING;
shimogamo 0:2a15bd367891 171 }
shimogamo 0:2a15bd367891 172
shimogamo 0:2a15bd367891 173 //Workout what the current state is.
shimogamo 0:2a15bd367891 174 channelA_.mode(PullUp);
shimogamo 0:2a15bd367891 175 int chanA = channelA_.read();
shimogamo 0:2a15bd367891 176 int chanB = chanA;
shimogamo 0:2a15bd367891 177 if(channelB !=NC){
shimogamo 0:2a15bd367891 178 channelB_.mode(PullUp);
shimogamo 0:2a15bd367891 179 chanB = channelB_.read();
shimogamo 0:2a15bd367891 180 chanBisvalid_ = true;
shimogamo 0:2a15bd367891 181 }
shimogamo 0:2a15bd367891 182
shimogamo 0:2a15bd367891 183 //2-bit state.
shimogamo 0:2a15bd367891 184 currState_ = (chanA << 1) | (chanB);
shimogamo 0:2a15bd367891 185 prevState_ = currState_;
shimogamo 0:2a15bd367891 186
shimogamo 0:2a15bd367891 187 //X2 encoding uses interrupts on only channel A.
shimogamo 0:2a15bd367891 188 //X4 encoding uses interrupts on channel A,
shimogamo 0:2a15bd367891 189 //and on channel B.
shimogamo 0:2a15bd367891 190 channelA_.rise(this, &RotaryEncoder::encode);
shimogamo 0:2a15bd367891 191 channelA_.fall(this, &RotaryEncoder::encode);
shimogamo 0:2a15bd367891 192
shimogamo 0:2a15bd367891 193 //If we're using X4 encoding, then attach interrupts to channel B too.
shimogamo 0:2a15bd367891 194 if (encoding == X4_ENCODING) {
shimogamo 0:2a15bd367891 195 channelB_.rise(this, &RotaryEncoder::encode);
shimogamo 0:2a15bd367891 196 channelB_.fall(this, &RotaryEncoder::encode);
shimogamo 0:2a15bd367891 197 }
shimogamo 0:2a15bd367891 198 //Index is optional.
shimogamo 0:2a15bd367891 199 if (index != NC) {
shimogamo 0:2a15bd367891 200 indexisvalid_ = true;
shimogamo 0:2a15bd367891 201 index_.rise(this, &RotaryEncoder::index);
shimogamo 0:2a15bd367891 202 }
shimogamo 0:2a15bd367891 203
shimogamo 0:2a15bd367891 204 }
shimogamo 0:2a15bd367891 205
shimogamo 0:2a15bd367891 206 void RotaryEncoder::reset(void) {
shimogamo 0:2a15bd367891 207
shimogamo 0:2a15bd367891 208 pulses_ = 0;
shimogamo 0:2a15bd367891 209 revolutions_ = 0;
shimogamo 0:2a15bd367891 210
shimogamo 0:2a15bd367891 211 }
shimogamo 0:2a15bd367891 212
shimogamo 0:2a15bd367891 213 int RotaryEncoder::getCurrentState(void) {
shimogamo 0:2a15bd367891 214
shimogamo 0:2a15bd367891 215 return currState_;
shimogamo 0:2a15bd367891 216
shimogamo 0:2a15bd367891 217 }
shimogamo 0:2a15bd367891 218
shimogamo 0:2a15bd367891 219 int RotaryEncoder::getPulses(void) {
shimogamo 0:2a15bd367891 220
shimogamo 0:2a15bd367891 221 return pulses_;
shimogamo 0:2a15bd367891 222
shimogamo 0:2a15bd367891 223 }
shimogamo 0:2a15bd367891 224
shimogamo 0:2a15bd367891 225 int RotaryEncoder::getRevolutions(void) {
shimogamo 0:2a15bd367891 226 if (indexisvalid_) {
shimogamo 0:2a15bd367891 227 } else {
shimogamo 0:2a15bd367891 228 if (encoding_ == X2_ENCODING) {
shimogamo 0:2a15bd367891 229 revolutions_ = pulses_/(pulsesPerRev_*2);
shimogamo 0:2a15bd367891 230 } else if (encoding_ == X4_ENCODING) {
shimogamo 0:2a15bd367891 231 revolutions_ = pulses_/(pulsesPerRev_*4);
shimogamo 0:2a15bd367891 232 }
shimogamo 0:2a15bd367891 233 }
shimogamo 0:2a15bd367891 234 return revolutions_;
shimogamo 0:2a15bd367891 235 }
shimogamo 0:2a15bd367891 236 float RotaryEncoder::getfloatrevolutions(void) {
shimogamo 0:2a15bd367891 237 if (indexisvalid_) {
shimogamo 0:2a15bd367891 238 return revolutions_+(float)(pulses_%(pulsesPerRev_*2))/(pulsesPerRev_*2);
shimogamo 0:2a15bd367891 239 } else {
shimogamo 0:2a15bd367891 240 if (encoding_ == X2_ENCODING) {
shimogamo 0:2a15bd367891 241 return (float)pulses_/(pulsesPerRev_*2);
shimogamo 0:2a15bd367891 242 } else if (encoding_ == X4_ENCODING) {
shimogamo 0:2a15bd367891 243 return (float)pulses_/(pulsesPerRev_*4);
shimogamo 0:2a15bd367891 244 }
shimogamo 0:2a15bd367891 245 }
shimogamo 0:2a15bd367891 246 return 0;
shimogamo 0:2a15bd367891 247
shimogamo 0:2a15bd367891 248 }
shimogamo 0:2a15bd367891 249
shimogamo 0:2a15bd367891 250 // +-------------+
shimogamo 0:2a15bd367891 251 // | X2 Encoding |
shimogamo 0:2a15bd367891 252 // +-------------+
shimogamo 0:2a15bd367891 253 //
shimogamo 0:2a15bd367891 254 // When observing states two patterns will appear:
shimogamo 0:2a15bd367891 255 //
shimogamo 0:2a15bd367891 256 // Counter clockwise rotation:
shimogamo 0:2a15bd367891 257 //
shimogamo 0:2a15bd367891 258 // 10 -> 01 -> 10 -> 01 -> ...
shimogamo 0:2a15bd367891 259 //
shimogamo 0:2a15bd367891 260 // Clockwise rotation:
shimogamo 0:2a15bd367891 261 //
shimogamo 0:2a15bd367891 262 // 11 -> 00 -> 11 -> 00 -> ...
shimogamo 0:2a15bd367891 263 //
shimogamo 0:2a15bd367891 264 // We consider counter clockwise rotation to be "forward" and
shimogamo 0:2a15bd367891 265 // counter clockwise to be "backward". Therefore pulse count will increase
shimogamo 0:2a15bd367891 266 // during counter clockwise rotation and decrease during clockwise rotation.
shimogamo 0:2a15bd367891 267 //
shimogamo 0:2a15bd367891 268 // +-------------+
shimogamo 0:2a15bd367891 269 // | X4 Encoding |
shimogamo 0:2a15bd367891 270 // +-------------+
shimogamo 0:2a15bd367891 271 //
shimogamo 0:2a15bd367891 272 // There are four possible states for a quadrature encoder which correspond to
shimogamo 0:2a15bd367891 273 // 2-bit gray code.
shimogamo 0:2a15bd367891 274 //
shimogamo 0:2a15bd367891 275 // A state change is only valid if of only one bit has changed.
shimogamo 0:2a15bd367891 276 // A state change is invalid if both bits have changed.
shimogamo 0:2a15bd367891 277 //
shimogamo 0:2a15bd367891 278 // Clockwise Rotation ->
shimogamo 0:2a15bd367891 279 //
shimogamo 0:2a15bd367891 280 // 00 01 11 10 00
shimogamo 0:2a15bd367891 281 //
shimogamo 0:2a15bd367891 282 // <- Counter Clockwise Rotation
shimogamo 0:2a15bd367891 283 //
shimogamo 0:2a15bd367891 284 // If we observe any valid state changes going from left to right, we have
shimogamo 0:2a15bd367891 285 // moved one pulse clockwise [we will consider this "backward" or "negative"].
shimogamo 0:2a15bd367891 286 //
shimogamo 0:2a15bd367891 287 // If we observe any valid state changes going from right to left we have
shimogamo 0:2a15bd367891 288 // moved one pulse counter clockwise [we will consider this "forward" or
shimogamo 0:2a15bd367891 289 // "positive"].
shimogamo 0:2a15bd367891 290 //
shimogamo 0:2a15bd367891 291 // We might enter an invalid state for a number of reasons which are hard to
shimogamo 0:2a15bd367891 292 // predict - if this is the case, it is generally safe to ignore it, update
shimogamo 0:2a15bd367891 293 // the state and carry on, with the error correcting itself shortly after.
shimogamo 0:2a15bd367891 294 void RotaryEncoder::encode(void) {
shimogamo 0:2a15bd367891 295
shimogamo 0:2a15bd367891 296 int change = 0;
shimogamo 0:2a15bd367891 297 int chanA = channelA_.read();
shimogamo 0:2a15bd367891 298 int chanB = chanA;
shimogamo 0:2a15bd367891 299 if(chanBisvalid_){
shimogamo 0:2a15bd367891 300 chanB = channelB_.read();
shimogamo 0:2a15bd367891 301 }
shimogamo 0:2a15bd367891 302
shimogamo 0:2a15bd367891 303 //2-bit state.
shimogamo 0:2a15bd367891 304 currState_ = (chanA << 1) | (chanB);
shimogamo 0:2a15bd367891 305
shimogamo 0:2a15bd367891 306 if (encoding_ == X2_ENCODING) {
shimogamo 0:2a15bd367891 307
shimogamo 0:2a15bd367891 308 //11->00->11->00 is counter clockwise rotation or "forward".
shimogamo 0:2a15bd367891 309 if ((prevState_ == 0x3 && currState_ == 0x0) ||
shimogamo 0:2a15bd367891 310 (prevState_ == 0x0 && currState_ == 0x3)) {
shimogamo 0:2a15bd367891 311
shimogamo 0:2a15bd367891 312 pulses_++;
shimogamo 0:2a15bd367891 313
shimogamo 0:2a15bd367891 314 }
shimogamo 0:2a15bd367891 315 //10->01->10->01 is clockwise rotation or "backward".
shimogamo 0:2a15bd367891 316 else if ((prevState_ == 0x2 && currState_ == 0x1) ||
shimogamo 0:2a15bd367891 317 (prevState_ == 0x1 && currState_ == 0x2)) {
shimogamo 0:2a15bd367891 318
shimogamo 0:2a15bd367891 319 pulses_--;
shimogamo 0:2a15bd367891 320
shimogamo 0:2a15bd367891 321 }
shimogamo 0:2a15bd367891 322
shimogamo 0:2a15bd367891 323 } else if (encoding_ == X4_ENCODING) {
shimogamo 0:2a15bd367891 324
shimogamo 0:2a15bd367891 325 //Entered a new valid state.
shimogamo 0:2a15bd367891 326 if (((currState_ ^ prevState_) != INVALID) && (currState_ != prevState_)) {
shimogamo 0:2a15bd367891 327 //2 bit state. Right hand bit of prev XOR left hand bit of current
shimogamo 0:2a15bd367891 328 //gives 0 if clockwise rotation and 1 if counter clockwise rotation.
shimogamo 0:2a15bd367891 329 change = (prevState_ & PREV_MASK) ^ ((currState_ & CURR_MASK) >> 1);
shimogamo 0:2a15bd367891 330
shimogamo 0:2a15bd367891 331 if (change == 0) {
shimogamo 0:2a15bd367891 332 change = -1;
shimogamo 0:2a15bd367891 333 }
shimogamo 0:2a15bd367891 334
shimogamo 0:2a15bd367891 335 pulses_ -= change;
shimogamo 0:2a15bd367891 336 }
shimogamo 0:2a15bd367891 337
shimogamo 0:2a15bd367891 338 }
shimogamo 0:2a15bd367891 339
shimogamo 0:2a15bd367891 340 prevState_ = currState_;
shimogamo 0:2a15bd367891 341
shimogamo 0:2a15bd367891 342 }
shimogamo 0:2a15bd367891 343
shimogamo 0:2a15bd367891 344 void RotaryEncoder::index(void) {
shimogamo 0:2a15bd367891 345
shimogamo 0:2a15bd367891 346 revolutions_++;
shimogamo 0:2a15bd367891 347
shimogamo 0:2a15bd367891 348 }