Raspi mit C/C++: Encoder per pigpio und callback auslesen?

[HaWe]

update:

mit Raspi 2B klappt es! Keine Zähl-Ausfälle mehr, selbst bei recht schnellen Umdrehungen, getestet mit Lego-Encodermotoren
(Auflösung: 1/2, d.h. 360 ticks/360°. Drehgeschwindigkeit 5 U/sec.).


Es wird über einen High Priority pthread Task ein Timer-Interrupt im 100µs Takt simuliert, und der Pi Quadcore hat jetzt die Performance, dies auch im Linux User Space sicher durchzuhalten - die Simulation verwendet dazu bisher insgesamt 4 Tasks mit unterschiedlicher Priorität:



Hier der Code :

share and enjoy!

// encoder test
// wiringPi,   
// Encoder Timer High Priority Thread
// ver 0007

// protected under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
// http://creativecommons.org/licenses/by-nc-sa/3.0/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <math.h>
#include <fcntl.h>
#include <string.h>
#include <sys/ioctl.h>
#include <stdint.h>
#include <errno.h>
#include <pthread.h>
#include <termios.h>

#include "VG/openvg.h"
#include "VG/vgu.h"
#include "fontinfo.h"
#include "shapes.h"

#include <wiringPi.h>
#include <wiringSerial.h>


#define  byte  uint8_t;

#define  MAXMOTORS    2   // max number of encoder motors

typedef struct {
      uint8_t    pd1, pd2, pwm;
      uint8_t    pqa, pqb;
      int32_t    motenc, oldenc;

}  tpimotor ;

tpimotor  motor[MAXMOTORS];

                               
/*************************************************************
* Encoder Handler Routine
*************************************************************/

volatile int8_t ISRab[MAXMOTORS];

// 1/2 resolution
int8_t enctab[16] = {0, 0,0,0,1,0,0,-1, 0,0,0,1,0,0,-1,0};

void updateEncoders() {   
  int i;    
  for( i=0; i<MAXMOTORS; ++i ) {   
    ISRab [ i] <<= 2;
    ISRab [ i] &=  0b00001100;
    ISRab [ i] |= (digitalRead( motor[ i].pqa ) << 1) | digitalRead(  motor[ i].pqb );
    motor[ i].motenc += enctab[ ISRab[ i] ];   
  }     

}


                             

void* thread3Go(void *)   // encoder high priority thread
{
   while(1) {
     updateEncoders();
     usleep(100);
   }         
   return NULL;
}

void* thread2Go(void *)
{
   while(1) {
      delay(10);
   }         
   return NULL;
}

void* thread1Go(void *)   // low priority display thread
{
   char  sbuf[128];
   while(1) {   
     delay(100);
   }         
   return NULL;
}

void* thread0Go(void *)
{
   char  sbuf[128];
   while(1) {
    sprintf(sbuf, " 0=%6ld    1=%6ld \n ",  motor[0].motenc, motor[1].motenc );
     printf(sbuf);
     delay(100);
   }         
   return NULL;
}




void setup() {
  int i;   
   
  // motor pins, wiringPi numbering (in parenthesis: BCM numbering)

     motor[0].pinQa = 5;   // (BCM 24) change for rotation direction
     motor[0].pinQb = 4;   // (BCM 23) change for rotation direction
     motor[0].pind1 =24;   // (BCM 19)
     motor[0].pind2 =25;   // (BCM 26)
     motor[0].pinpwm= 1;   // (BCM 18) hardware pwm
     
     motor[1].pinQa = 0;   // (BCM 17) change for rotation direction
     motor[1].pinQb = 2;   // (BCM 27) change for rotation direction
     motor[1].pind1 =21;   // (BCM 5)
     motor[1].pind2 =22;   // (BCM 6)
     motor[1].pinpwm=23;   // (BCM 13) hardware pwm   

     
     for( i=0; i< MAXMOTORS; ++i)  {       
        pinMode(motor[i].pqa, INPUT);        // encA   
        pinMode(motor[i].pqb, INPUT);        // encB   
        pinMode(motor[i].pd1, OUTPUT);       // dir-1   
        pinMode(motor[i].pd2, OUTPUT);       // dir-2   
        pinMode(motor[i].pwm ,OUTPUT);       // pwm
       
        motor[i].motenc = 0;
        motor[i].oldenc = 0;
        ISRab[i] = 0;
   }
}





int main() {
    char  sbuf[128];
    pthread_t thread0, thread1, thread2, thread3;
   
    wiringPiSetup();   
    if(wiringPiSetup() == -1) return 1;   
   
    setup();
   
    struct sched_param param;
   
   
    pthread_create(&thread0, NULL, thread0Go, NULL);
    param.sched_priority = 10;
    pthread_setschedparam(thread0, SCHED_RR, &param);
   
    pthread_create(&thread1, NULL, thread1Go, NULL);
    param.sched_priority = 25;
    pthread_setschedparam(thread1, SCHED_RR, &param);
   
    pthread_create(&thread2, NULL, thread2Go, NULL);
    param.sched_priority = 50;
    pthread_setschedparam(thread2, SCHED_RR, &param);
   
    pthread_create(&thread3, NULL, thread3Go, NULL);
    param.sched_priority = 90;
    pthread_setschedparam(thread3, SCHED_RR, &param);
   
   
    pthread_join(thread0, NULL);
    pthread_join(thread1, NULL);
    pthread_join(thread2, NULL);
    pthread_join(thread3, NULL);
   
    exit(0);
   
}

# build:
 g++ -Wall -I/opt/vc/include -I/opt/vc/include/interface/vmcs_host/linux -I/opt/vc/include/interface/vcos/pthreads -o "%e" "%f" -pthread -lshapes -L/opt/vc/lib -lOpenVG -lEGL -lrt -lwiringPi -lpigpio