cm5-1

#include <stdio.h>
#include <stdint.h>
#include <string.h>

#define WIDTH 64
#define HEIGHT 48

#define bitRead(value, bit) (((value) >> (bit)) & 0x01)

int buffer[WIDTH+2][HEIGHT+2];

static uint16_t fn(uint16_t x)
{
    return ((x >> 0) ^ (x >> 4) ^ (x >> 13) ^ (x >> 15)) & 1;
}

void print_screen()
{
    uint16_t i,j;
    int pixel;
    char v[WIDTH];
    for (j = 0; j<HEIGHT; j++){
        for (i = 0; i<WIDTH; i++){
            pixel=buffer[i][j];

            if (j&4){
                if (pixel==0) v[WIDTH-i]=' ';
                else v[WIDTH-i]='X';
            }
            else if (pixel==0) v[i]=' ';
            else v[i]='X';
        }
        v[WIDTH] = '\0';
        puts(v);
    }
}

int main(void)
{
    uint16_t gen = 1;
    int i,j;
    for (;;)
    {
        /* ANSI sequence to clear terminal */
        fputs("\033[2J\033[1;1H", stdout);

        for (i = 0; i < HEIGHT; i++)
        {
            uint16_t gen_bit = fn(gen);
            gen = (gen_bit << 15) | (gen >> 1);
            // uint16_t bit = ((gen >> 0) & (gen >> 1)) & 1;
            uint16_t bit = bitRead(gen,0) & bitRead(gen,1);

            buffer[WIDTH][i]=bit;
        }

        for(j=0; j<HEIGHT; j++) {
            for(i=0; i<WIDTH; i++){
                if (buffer[i+1][j]==1) buffer[i][j]=1;
                else buffer[i][j]=0;
            }
        }
        print_screen();

        fflush(stdout);
        usleep(70000);
    }

    return 0;
}