First Last / Encoder

Library to read out speed and position from a quadrature encoder. This library uses X2 decoding.

Dependents:   BMT-K9_encoder BMT-K9-Regelaar K9motoraansturing_copy EMGverwerking ... more

encoder.h@6:18b000b443af, 2014-09-29 (annotated)

Committer:
vsluiter
Date:
Mon Sep 29 20:47:37 2014 +0000
Revision:
6:18b000b443af
Parent:
5:04c4a90c7a0a 
Updated documentation

Who changed what in which revision?

UserRevisionLine numberNew contents of line
vsluiter 0:c90b36abcbf8 1 #ifndef _ENCODER_H_
vsluiter 0:c90b36abcbf8 2 #define _ENCODER_H_
vsluiter 0:c90b36abcbf8 3
vsluiter 0:c90b36abcbf8 4 #include "mbed.h"
vsluiter 6:18b000b443af 5
vsluiter 1:2dd7853c911a 6 /** Encoder class.
vsluiter 1:2dd7853c911a 7 * Used to read out incremental position encoder. Decodes position in X2 configuration.
vsluiter 1:2dd7853c911a 8 *
vsluiter 3:dcb7bdc73882 9 * Speed estimation is very crude and computationally intensive. Turned off by default
vsluiter 3:dcb7bdc73882 10 *
vsluiter 1:2dd7853c911a 11 * Example:
vsluiter 1:2dd7853c911a 12 * @code
vsluiter 1:2dd7853c911a 13 * #include "mbed.h"
vsluiter 1:2dd7853c911a 14 * #include "Encoder.h"
vsluiter 1:2dd7853c911a 15 *
vsluiter 3:dcb7bdc73882 16 * Encoder motor1(PTD0,PTC9,true);
vsluiter 1:2dd7853c911a 17 * Serial pc(USBTX,USBRX);
vsluiter 1:2dd7853c911a 18 * pc.baud(115200);
vsluiter 1:2dd7853c911a 19 * while(1) {
vsluiter 1:2dd7853c911a 20 * wait(0.2);
vsluiter 1:2dd7853c911a 21 * pc.printf("pos: %d, speed %f \r\n",motor1.getPosition(), motor1.getSpeed());
vsluiter 1:2dd7853c911a 22 * }
vsluiter 1:2dd7853c911a 23 * @endcode
vsluiter 1:2dd7853c911a 24 */
vsluiter 0:c90b36abcbf8 25 class Encoder
vsluiter 0:c90b36abcbf8 26 {
vsluiter 0:c90b36abcbf8 27 public:
vsluiter 1:2dd7853c911a 28 /** Create Encoder instance
vsluiter 1:2dd7853c911a 29 @param int_a Pin to be used as InterruptIn! Be careful, as not all pins on all platforms may be used as InterruptIn.
vsluiter 1:2dd7853c911a 30 @param int_b second encoder pin, used as DigitalIn. Can be any DigitalIn pin, not necessarily on InterruptIn location
vsluiter 6:18b000b443af 31 @param speed boolean value to determine whether speed calculation is done in interrupt routine. Default false (no speed calculation)
vsluiter 1:2dd7853c911a 32 */
vsluiter 4:69be34f39c9f 33
vsluiter 3:dcb7bdc73882 34 Encoder(PinName int_a, PinName int_b, bool speed=false);
vsluiter 1:2dd7853c911a 35 /** Request position
vsluiter 1:2dd7853c911a 36 @returns current position in encoder counts
vsluiter 1:2dd7853c911a 37 */
vsluiter 0:c90b36abcbf8 38 int32_t getPosition(){return m_position;}
vsluiter 1:2dd7853c911a 39 /** Overwrite position
vsluiter 1:2dd7853c911a 40 @param pos position to be written
vsluiter 1:2dd7853c911a 41 */
vsluiter 0:c90b36abcbf8 42 void setPosition(int32_t pos){m_position = pos;}
vsluiter 1:2dd7853c911a 43 /** Request speed
vsluiter 1:2dd7853c911a 44 @returns current speed
vsluiter 1:2dd7853c911a 45 */
vsluiter 0:c90b36abcbf8 46 float getSpeed(){return m_speed;}
vsluiter 0:c90b36abcbf8 47 private:
vsluiter 0:c90b36abcbf8 48 void encoderFalling(void);
vsluiter 0:c90b36abcbf8 49 void encoderRising(void);
vsluiter 3:dcb7bdc73882 50 bool m_speed_enabled;
vsluiter 0:c90b36abcbf8 51 Timer EncoderTimer;
vsluiter 5:04c4a90c7a0a 52 Timeout EncoderTimeout;
vsluiter 0:c90b36abcbf8 53 InterruptIn pin_a;
vsluiter 0:c90b36abcbf8 54 DigitalIn pin_b;
vsluiter 0:c90b36abcbf8 55 int32_t m_position;
vsluiter 0:c90b36abcbf8 56 float m_speed;
vsluiter 0:c90b36abcbf8 57 void timeouthandler(void);
vsluiter 0:c90b36abcbf8 58 bool zero_speed;
vsluiter 0:c90b36abcbf8 59 };
vsluiter 0:c90b36abcbf8 60
vsluiter 0:c90b36abcbf8 61
vsluiter 0:c90b36abcbf8 62 #endif //_ENCODER_H_