Create a Game in C language with the 8051 IDE MCU

I am trying to develop a game within the microprocessor curriculum, so the game is a doll that has to dodge bombs, so I have to create the doll, the bombs and get them to play. I already have a lot of code but I think it gets stuck in a while loop and I do not understand why. Is exposing here a piece of my code are able to help me ??

void main (void)
{   
unsigned char i,counter=1;

start=0;
end=0;
IE=0b10000101;
En=1;
LCD_init ();
while(start!=0);
while(end==1);
Inicio();
CriarBonecoBomba();
x=0;
y=0;
score=0;

for(i=0;i<16;i++)
{
    var[0][i]=' ';
    var[1][i]=' ';
}
while(end==0) // salta da 1a interrupção la ao fundo para aqui e não sai daqui
{
    while (start==1)
    {
        MovBoneco();
        desloca_esq();
        if((counter+3)%6==0)
            cria_bomba(1);
        else
            if(counter%6==0)
                cria_bomba(2);
            else
                cria_bomba(0);
        if(var[y][x]==1|| 1==var[y][x-1])
        {
            LCD_comando(0b10000000);
            LCD_date(' ');
            LCD_date(' ');
            LCD_date(' ');
            LCD_date('G');
            LCD_date('A');  
            LCD_date('M');
            LCD_date('E');
            LCD_date(' ');
            LCD_date('O');
            LCD_date('V');
            LCD_date('E');
            LCD_date('R');
            while(1);
        }
    MovBoneco();
    AtualizarLCD();
    counter++;
    if(var[0][0]==1||var[1][0]==1)
        score=score+5;
    display7segmentos();
}
}
}

void RSIEXT0(void)__interrupt (0)
{
start=1;
}

void RSIEXT1(void)__interrupt (2)
{
end==1;
}