function $_(id) {
    return document.getElementById(id);
}

function onKEYUP(e, t1, t2) {
        if (window.event) {
            tecla = e.keyCode;
        }
        if (e.which) {
            tecla = e.which;
        }
        if (tecla == 13) {
            t2.focus();
        }
} 

function mostrar(capa) {
	var total = capa.length;
	for (var i = 0; i < total; i++)
		$_(capa).style.display = "block";
}

function ocultar(capa) {
	var total = capa.length;
	for (var i = 0; i < total; i ++)
		$_(capa).style.display = "none";
}

function mayusculas(cadena) {
    var result="";
    var str = cadena.split('');
 
    for(i=0; i<=str.length-1; i++) {
        str[i] = str[i].toUpperCase();
        result+=str[i];
    }
    return(result); //alert(result);
}