I have a ZyBo circuit board which has a ArmV7 processor. I wrote a C program to output a clock and a corresponding data sequence on a PMOD. The PMOD has a switching speed of up to 50MHz. However, my program's created clock only has a max frequency of 115 Hz. I need this program to output as fast as possible because the PMOD I'm using is capable of 50MHz. I compiled my program with the following code line:

gcc -ofast (c_program)

Here is some sample code:

#include <stdio.h>
#include <stdlib.h>

#define ARRAYSIZE 511
//________________________________________

//macro for the SIGNAL PMOD
//________________________________________
//DATA 
//ZYBO Use Pin JE1
#define INIT_SIGNAL system("echo 54 > /sys/class/gpio/export"); system("echo out > /sys/class/gpio/gpio54/direction");
#define SIGNAL_ON system("echo 1 > /sys/class/gpio/gpio54/value");
#define SIGNAL_OFF system("echo 0 > /sys/class/gpio/gpio54/value");
//________________________________________

//macro for the "CLOCK" PMOD
//________________________________________
//CLOCK 
//ZYBO Use Pin JE4
#define INIT_MYCLOCK system("echo 57 > /sys/class/gpio/export"); system("echo out > /sys/class/gpio/gpio57/direction");
#define MYCLOCK_ON system("echo 1 > /sys/class/gpio/gpio57/value");
#define MYCLOCK_OFF system("echo 0 > /sys/class/gpio/gpio57/value");

int main(void){

int myarray[ARRAYSIZE] = {//hard coded array for signal data
    1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,0,1,0,1,0,0,1,1,0,0,1,1,0,1,0,0,0,0,0,1,0,0,1,1,1,0,0,1,1,1,0,1,1,1,1,0,0,1,0,0,0,1,0,1,0,0,1,1,1,0,0,1,0,1,0,1,0,0,1,0,1,1,0,1,0,1,1,0,0,1,1,1,1,0,0,1,0,1,0,0,1,1,1,1,1,1,0,0,1,0,0,1,1,0,1,0,0,0,0,1,0,0,0,1,1,0,0,1,0,1,1,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,0,1,0,1,1,1,1,0,1,1,0,1,0,0,1,0,0,0,1,0,1,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,1,0,1,1,0,0,0,0,0,0,0,0,1,0,1,1,0,1,1,1,1,1,0,0,1,1,1,0,0,1,1,0,1,1,0,1,1,1,0,0,1,1,1,1,1,0,0,1,0,1,0,1,0,1,1,0,1,0,0,0,1,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,0,1,0,0,0,0,1,1,1,0,1,1,1,1,0,1,1,0,1,0,1,0,1,0,0,1,0,1,1,1,0,1,1,1,0,0,1,1,1,0,1,0,0,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,0,1,0,1,1,1,1,1,1,1,0,0,0,0,0,1,1,0,1,1,1,1,1,1,1,1,0,1,1,0,1,0,0,0,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,0,1,1,1,0,1,0,1,1,1,0,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,1,0,0,1,0,0,1,0,1,1,1,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,0,1,1,0,1,1,0,0,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,1,1,0,1,1,0,0,0,0,1,1,0,1,1,0,1,1,1,1,1,1,1,0,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0
    };

INIT_SIGNAL
INIT_MYCLOCK;
//infinite loop
int i;
do{
    i = 0;
    do{
        /*
        1020 is chosen because it is twice the size needed allowing for the changes in the clock.
        (511= 0-510, 510*2= 1020 ==> 0-1020 needed, so 1021 it is)
        */
        if((i%2)==0)
        {
            MYCLOCK_ON;
            if(myarray[i/2] == 1){
                SIGNAL_ON;
            }else{
                SIGNAL_OFF;
            }
        }
        else if((i%2)==1)
        {
            MYCLOCK_OFF;
            //dont need to change the signal since it will just stay at whatever it was.
        }
        ++i;
    } while(i < 1021);
} while(1);
return 0;
}

I'm using the 'system' call to tell the system to output 1 volt or 0 volts onto a pin on the board (to represent the data signal and clock signal. One pin for the data and another for the clock). That was the only way I knew to tell the system to output a voltage.

What can I do to make my executable program output to be at least in the magnitude of MegaHertz?