File content as of revision 0:94c1e7624b95:

#include "mbed.h"
#include "SDFileSystem.h"


SDFileSystem sd(p5, p6, p7, p8, "sd");
AnalogIn  pitot(p18);

DigitalOut  led1(LED1);
DigitalOut  led2(LED2);
DigitalOut  led3(LED3);
DigitalOut  led4(LED4);
DigitalIn   logging(p19);
DigitalOut stop_counter(p20);
PwmOut servo(p21);
Timer t;

float pout;
double time_pulse, length, pres, vel;
float sp_of_s;
float  temp = 0;


int main() {
    led1 = 0.0;
    led2 = 0.0;
    led3 = 0.0;
    led4 = 0.0;
    wait(0.5);
    
    while(logging < 0.5) {
        led1 = 1;
        led4 = 1;
        wait(0.5);
        led1 = 0;
        led4 = 0;
        wait(0.5);
        }
        
    wait(3);
    //setup log file    
    FILE *fp = fopen("/sd/TFLOG.csv", "w");
    if(fp == NULL) {
        error("Could not open file for write\n\r");
        }
        
    fprintf(fp, "altitude, velocity\n");    
    stop_counter = 0;
    led1 = 1;
    led4 = 1;
    
    while(logging < 0.5){
        //get velocity
        pres = 500 * (pitot.read()*5-0.25)/3.75*0.95-15.5;
            
            if(pres > 0){
                vel=sqrt(2.0/1.225*pres);
            }
            else{
            vel=-sqrt(2.0/1.225*pres*(-1.0));
            }
        
        fprintf(fp,"%6.4f\n ", vel);
        //servo.pulsewidth(pout);
        //wait(0.04888-time_pulse/1000000);
        wait(0.01);
    }
    stop_counter = 1;
    fclose(fp);
    led1 = 0;
    led4 = 0;
}