r_test1_2017_10_11_Wed_A
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Revision 1:8658787f9ec5, committed 2017-10-11
- Comitter:
- shobonwarrior
- Date:
- Wed Oct 11 08:14:24 2017 +0000
- Parent:
- 0:5c2ad81551aa
- Commit message:
- r_test1_2017/10/11/Wed_A
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diff -r 5c2ad81551aa -r 8658787f9ec5 QEI.cpp --- a/QEI.cpp Thu Sep 02 16:48:55 2010 +0000 +++ b/QEI.cpp Wed Oct 11 08:14:24 2017 +0000 @@ -1,289 +1,184 @@ -/** - * @author Aaron Berk - * - * @section LICENSE - * - * Copyright (c) 2010 ARM Limited - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - * - * @section DESCRIPTION - * - * Quadrature Encoder Interface. - * - * A quadrature encoder consists of two code tracks on a disc which are 90 - * degrees out of phase. It can be used to determine how far a wheel has - * rotated, relative to a known starting position. - * - * Only one code track changes at a time leading to a more robust system than - * a single track, because any jitter around any edge won't cause a state - * change as the other track will remain constant. - * - * Encoders can be a homebrew affair, consisting of infrared emitters/receivers - * and paper code tracks consisting of alternating black and white sections; - * alternatively, complete disk and PCB emitter/receiver encoder systems can - * be bought, but the interface, regardless of implementation is the same. - * - * +-----+ +-----+ +-----+ - * Channel A | ^ | | | | | - * ---+ ^ +-----+ +-----+ +----- - * ^ ^ - * ^ +-----+ +-----+ +-----+ - * Channel B ^ | | | | | | - * ------+ +-----+ +-----+ +----- - * ^ ^ - * ^ ^ - * 90deg - * - * The interface uses X2 encoding by default which calculates the pulse count - * based on reading the current state after each rising and falling edge of - * channel A. - * - * +-----+ +-----+ +-----+ - * Channel A | | | | | | - * ---+ +-----+ +-----+ +----- - * ^ ^ ^ ^ ^ - * ^ +-----+ ^ +-----+ ^ +-----+ - * Channel B ^ | ^ | ^ | ^ | ^ | | - * ------+ ^ +-----+ ^ +-----+ +-- - * ^ ^ ^ ^ ^ - * ^ ^ ^ ^ ^ - * Pulse count 0 1 2 3 4 5 ... - * - * This interface can also use X4 encoding which calculates the pulse count - * based on reading the current state after each rising and falling edge of - * either channel. - * - * +-----+ +-----+ +-----+ - * Channel A | | | | | | - * ---+ +-----+ +-----+ +----- - * ^ ^ ^ ^ ^ - * ^ +-----+ ^ +-----+ ^ +-----+ - * Channel B ^ | ^ | ^ | ^ | ^ | | - * ------+ ^ +-----+ ^ +-----+ +-- - * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ - * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ - * Pulse count 0 1 2 3 4 5 6 7 8 9 ... - * - * It defaults - * - * An optional index channel can be used which determines when a full - * revolution has occured. - * - * If a 4 pules per revolution encoder was used, with X4 encoding, - * the following would be observed. - * - * +-----+ +-----+ +-----+ - * Channel A | | | | | | - * ---+ +-----+ +-----+ +----- - * ^ ^ ^ ^ ^ - * ^ +-----+ ^ +-----+ ^ +-----+ - * Channel B ^ | ^ | ^ | ^ | ^ | | - * ------+ ^ +-----+ ^ +-----+ +-- - * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ - * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ - * ^ ^ ^ +--+ ^ ^ +--+ ^ - * ^ ^ ^ | | ^ ^ | | ^ - * Index ------------+ +--------+ +----------- - * ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ - * Pulse count 0 1 2 3 4 5 6 7 8 9 ... - * Rev. count 0 1 2 - * - * Rotational position in degrees can be calculated by: - * - * (pulse count / X * N) * 360 - * - * Where X is the encoding type [e.g. X4 encoding => X=4], and N is the number - * of pulses per revolution. - * - * Linear position can be calculated by: - * - * (pulse count / X * N) * (1 / PPI) - * - * Where X is encoding type [e.g. X4 encoding => X=44], N is the number of - * pulses per revolution, and PPI is pulses per inch, or the equivalent for - * any other unit of displacement. PPI can be calculated by taking the - * circumference of the wheel or encoder disk and dividing it by the number - * of pulses per revolution. - */ - -/** - * Includes - */ #include "QEI.h" - + QEI::QEI(PinName channelA, PinName channelB, PinName index, int pulsesPerRev, - Encoding encoding) : channelA_(channelA), channelB_(channelB), + Encoding encoding + ) : channelA_(channelA), channelB_(channelB), index_(index) { - + pulses_ = 0; revolutions_ = 0; pulsesPerRev_ = pulsesPerRev; encoding_ = encoding; - + //Workout what the current state is. int chanA = channelA_.read(); int chanB = channelB_.read(); - + //2-bit state. currState_ = (chanA << 1) | (chanB); prevState_ = currState_; - - //X2 encoding uses interrupts on only channel A. - //X4 encoding uses interrupts on channel A, - //and on channel B. + channelA_.rise(this, &QEI::encode); channelA_.fall(this, &QEI::encode); - - //If we're using X4 encoding, then attach interrupts to channel B too. + + if (encoding == X4_ENCODING) { channelB_.rise(this, &QEI::encode); channelB_.fall(this, &QEI::encode); } - //Index is optional. if (index != NC) { index_.rise(this, &QEI::index); } - + } - + void QEI::reset(void) { - + pulses_ = 0; revolutions_ = 0; - + round_rev = 0; + sumangle = angle_ =0; } - +void QEI::set(int pul , int rev) { + + pulses_ = pul; + revolutions_ = rev; + +} int QEI::getCurrentState(void) { - + return currState_; - + } - + int QEI::getPulses(void) { - + return pulses_; - + +} + +int QEI::getRevolutions(void) { + + return revolutions_; + } - -int QEI::getRevolutions(void) { - - return revolutions_; - +double QEI::getAngle() +{ + return angle_; +} +int QEI::getAng_rev() +{ + return round_rev; +} +double QEI::getSumangle() +{ + return sumangle; } - -// +-------------+ -// | X2 Encoding | -// +-------------+ -// -// When observing states two patterns will appear: -// -// Counter clockwise rotation: -// -// 10 -> 01 -> 10 -> 01 -> ... -// -// Clockwise rotation: -// -// 11 -> 00 -> 11 -> 00 -> ... -// -// We consider counter clockwise rotation to be "forward" and -// counter clockwise to be "backward". Therefore pulse count will increase -// during counter clockwise rotation and decrease during clockwise rotation. -// -// +-------------+ -// | X4 Encoding | -// +-------------+ -// -// There are four possible states for a quadrature encoder which correspond to -// 2-bit gray code. -// -// A state change is only valid if of only one bit has changed. -// A state change is invalid if both bits have changed. -// -// Clockwise Rotation -> -// -// 00 01 11 10 00 -// -// <- Counter Clockwise Rotation -// -// If we observe any valid state changes going from left to right, we have -// moved one pulse clockwise [we will consider this "backward" or "negative"]. -// -// If we observe any valid state changes going from right to left we have -// moved one pulse counter clockwise [we will consider this "forward" or -// "positive"]. -// -// We might enter an invalid state for a number of reasons which are hard to -// predict - if this is the case, it is generally safe to ignore it, update -// the state and carry on, with the error correcting itself shortly after. + +double QEI::getRPM() +{ + static double prev_angle; + Mper.stop(); + + RPM = (sumangle - prev_angle) / Mper.read() * 60.0 / 360; + Mper.reset(); + Mper.start(); + prev_angle = sumangle; + return RPM; +} +double QEI::getRPS() +{ + static double prev_angle; + Rper.stop(); + + RPS = (sumangle - prev_angle) / Rper.read() / 360; + Rper.reset(); + Rper.start(); + prev_angle = sumangle; + return RPS; +} +double QEI::getRPMS() +{ static double prev_angle; + MSper.stop(); + + RPMS = (sumangle - prev_angle) / (double)MSper.read_ms() / 360; + MSper.reset(); + MSper.start(); + prev_angle = sumangle; + return RPMS; +} +double QEI::getRPUS() +{ static double prev_angle; + USper.stop(); + + RPUS = (sumangle - prev_angle) / (double)USper.read_us() / 360; + USper.reset(); + USper.start(); + prev_angle = sumangle; + return RPUS; +} void QEI::encode(void) { - + int change = 0; int chanA = channelA_.read(); int chanB = channelB_.read(); - - //2-bit state. + currState_ = (chanA << 1) | (chanB); - + if (encoding_ == X2_ENCODING) { - - //11->00->11->00 is counter clockwise rotation or "forward". + if ((prevState_ == 0x3 && currState_ == 0x0) || (prevState_ == 0x0 && currState_ == 0x3)) { - + pulses_++; - + angle_pulses++; + } - //10->01->10->01 is clockwise rotation or "backward". else if ((prevState_ == 0x2 && currState_ == 0x1) || (prevState_ == 0x1 && currState_ == 0x2)) { - + pulses_--; - + angle_pulses--; + } - + } else if (encoding_ == X4_ENCODING) { - - //Entered a new valid state. + if (((currState_ ^ prevState_) != INVALID) && (currState_ != prevState_)) { - //2 bit state. Right hand bit of prev XOR left hand bit of current - //gives 0 if clockwise rotation and 1 if counter clockwise rotation. change = (prevState_ & PREV_MASK) ^ ((currState_ & CURR_MASK) >> 1); - + if (change == 0) { change = -1; } - + pulses_ -= change; + angle_pulses -= change; } - + } - + angle_ = angle_pulses*360/((double)pulsesPerRev_*4); + sumangle = pulses_*360/((double)pulsesPerRev_*4); + if(angle_>=360) + { + angle_pulses = angle_ = 0; + round_rev++; + } + else if(angle_<=-360) + { + angle_pulses = angle_ = 0; + round_rev--; + } prevState_ = currState_; - } - + void QEI::index(void) { - + revolutions_++; - + } + + + \ No newline at end of file
diff -r 5c2ad81551aa -r 8658787f9ec5 QEI.h --- a/QEI.h Thu Sep 02 16:48:55 2010 +0000 +++ b/QEI.h Wed Oct 11 08:14:24 2017 +0000 @@ -123,122 +123,99 @@ * of pulses per revolution. */ + + #ifndef QEI_H #define QEI_H - -/** - * Includes - */ + + #include "mbed.h" - -/** - * Defines - */ + + #define PREV_MASK 0x1 //Mask for the previous state in determining direction //of rotation. #define CURR_MASK 0x2 //Mask for the current state in determining direction //of rotation. #define INVALID 0x3 //XORing two states where both bits have changed. - -/** - * Quadrature Encoder Interface. - */ + class QEI { - + public: - + typedef enum Encoding { - + X2_ENCODING, X4_ENCODING - + } Encoding; - - /** - * Constructor. - * - * Reads the current values on channel A and channel B to determine the - * initial state. - * - * Attaches the encode function to the rise/fall interrupt edges of - * channels A and B to perform X4 encoding. - * - * Attaches the index function to the rise interrupt edge of channel index - * (if it is used) to count revolutions. - * - * @param channelA mbed pin for channel A input. - * @param channelB mbed pin for channel B input. - * @param index mbed pin for optional index channel input, - * (pass NC if not needed). - * @param pulsesPerRev Number of pulses in one revolution. - * @param encoding The encoding to use. Uses X2 encoding by default. X2 - * encoding uses interrupts on the rising and falling edges - * of only channel A where as X4 uses them on both - * channels. - */ + + QEI(PinName channelA, PinName channelB, PinName index, int pulsesPerRev, Encoding encoding = X2_ENCODING); - - /** - * Reset the encoder. - * - * Sets the pulses and revolutions count to zero. - */ + void reset(void); - - /** - * Read the state of the encoder. - * - * @return The current state of the encoder as a 2-bit number, where: - * bit 1 = The reading from channel B - * bit 2 = The reading from channel A - */ + int getCurrentState(void); - - /** - * Read the number of pulses recorded by the encoder. - * - * @return Number of pulses which have occured. - */ + + + void set(int pul , int rev); + int getPulses(void); - - /** - * Read the number of revolutions recorded by the encoder on the index channel. - * - * @return Number of revolutions which have occured on the index channel. - */ + int getRevolutions(void); - + + int getAng_rev(); + + double getAngle(); + double getSumangle(); + double getRPM(); + double getRPS(); + double getRPMS(); + double getRPUS(); + int pulsesPerRev_; private: - - /** - * Update the pulse count. - * - * Called on every rising/falling edge of channels A/B. - * - * Reads the state of the channels and determines whether a pulse forward - * or backward has occured, updating the count appropriately. - */ + Timer Mper , Rper ,MSper ,USper; + Ticker Tick; + double RPM , RPS ,RPMS , RPUS; + void encode(void); - - /** - * Called on every rising edge of channel index to update revolution - * count by one. - */ + + void index(void); - + Encoding encoding_; - + InterruptIn channelA_; InterruptIn channelB_; InterruptIn index_; - - int pulsesPerRev_; + int round_rev; + int prevState_; int currState_; - + double angle_ , sumangle; + int angle_pulses; volatile int pulses_; volatile int revolutions_; - + }; + +#endif + +/* +Repository toolbox +Import into Compiler + Export to desktop IDE +Repository details +Type: Library +Created: 17 4月 2015 +Imports: 195 +Forks: 1 +Commits: 1 +Dependents: 0 +Dependencies: 0 +Followers: 5 +Software licencing information -#endif /* QEI_H */ + +The code in this repository is Apache licensed. + +*/ \ No newline at end of file