File content as of revision 0:3858dd3441ba:

#include "mbed.h"
#include "rotary_encoder_ab_phase.hpp"

#define sample_num_max  10000
#define sampling_period  500
#define reel_radius      25.0 //  unit : mm
#define countPerRevol    4000

rotary_encoder_ab_phase encoder(TIM1,1000);

DigitalOut myled(LED1);
DigitalIn button(USER_BUTTON);

Serial pc(USBTX, USBRX);

Timer timer;


uint32_t sampling_count = 0;
int16_t sample_data[sample_num_max] = {0};
int32_t sample_time_us[sample_num_max] = {0};


int32_t get_encoder(void){
    static int32_t counts = 0;
    static int32_t p_raw_counts = 0;
    int32_t raw_counts;
    
    raw_counts=encoder.get_counts();
    
    if((raw_counts - p_raw_counts) > 30000){
        counts -= 65535 - (raw_counts - p_raw_counts);
    }
    else if((raw_counts - p_raw_counts) < -30000){
        counts += 65535 - (p_raw_counts - raw_counts);
    }
    else{
        counts += raw_counts - p_raw_counts;
    }
    p_raw_counts = raw_counts;
    return counts;
}

int32_t get_encoder_diff(void){
    int32_t diff = 0;
    static int32_t p_raw_counts = 0;
    int32_t raw_counts;
    
    raw_counts=encoder.get_counts();
    
    if((raw_counts - p_raw_counts) > 30000){
        diff = 65535 - (raw_counts - p_raw_counts);
    }
    else if((raw_counts - p_raw_counts) < -30000){
        diff = 65535 - (p_raw_counts - raw_counts);
    }
    else{
        diff = raw_counts - p_raw_counts;
    }
    p_raw_counts = raw_counts;
    return diff;
}

double dabs(double val){
    if(val < 0.0)return val * -1;
    return val;
}

int main() {
    
    int32_t ex_time_us = 0;
    int32_t interval_us = 0;
    double revolPerSec;
    double speed = 0.0;
    
    pc.baud(115200);
    
    encoder.start();
    
    //pc.printf("Hello\n");
    wait_ms(100);
    
    //pc.printf("wait starting ...\n");
    while(button == 1);
    //pc.printf("sampling ...\n");
    
    get_encoder_diff();
    timer.start();
    timer.reset();
    while(button == 0) {
        
        wait_us(sampling_period);
        
        sample_time_us[sampling_count] = timer.read_us();
        sample_data[sampling_count] = get_encoder_diff();
        
        sampling_count += 1;
        if(sampling_count >= sample_num_max - 1){
            break;
        }
        
    }
    
    //pc.printf("sampling finished\n");
    
    for(uint32_t count = 0; count < sampling_count; count++){
        interval_us = sample_time_us[count] - ex_time_us;
        ex_time_us = sample_time_us[count];
        revolPerSec = (double)sample_data[count] * 1000000.0 / countPerRevol / (double)interval_us;
        speed = 2 * 3.14159265 * reel_radius / 1000.0 * revolPerSec;
        pc.printf("%d, %f\n", sample_time_us[count], speed);
    }
    
    while(1);
    
}