void disable_pcode()
{
    poke(0x3c,1);
}

void enable_pcode()
{
    poke(0x3c,0);
}

int sgetchar()
{
    int a;
    while ((peek(0x102e)&0x10)==0);
    return peek(0x102f);
}

int poll()
{
    if ((peek(0x102e)&0x10)==0) return 0;
    else return peek(0x102f)&0x7f;
}

void sputchar(int c)
{
    int i=0;
    while ((peek(0x102e)&0x80)==0 && i<100) {
        i++;
    }    
    poke(0x102f,c);
}