File content as of revision 0:b744a6c42a5a:

#include "mbed.h"

void respondtoPC() ;

Serial pc(USBTX, USBRX); // tx, rx

DigitalOut myled(LED1);
volatile int test ;

int main() {
    struct tm t;
    test = 0 ;
    pc.attach(respondtoPC) ;
    while (1) {
        myled = !myled ;
        if(test == 1) {
            pc.attach(NULL);
            printf("Enter current date and time:  \n");
            printf("YYYY MM DD HH MM SS[enter]  \n");
            scanf("%d %d %d %d %d %d", &t.tm_year, &t.tm_mon, &t.tm_mday
                  , &t.tm_hour, &t.tm_min, &t.tm_sec);
// adjust for tm structure required values
            t.tm_year = t.tm_year - 1900;
            t.tm_mon = t.tm_mon - 1;
// set the time
            set_time(mktime(&t));
            printf("set time\n");
            pc.attach(respondtoPC);    
        }
        wait(1) ;
    }
}

void respondtoPC() {
    char dummy = pc.getc() ;
    test++ ;
}