Converter para maiúsculo na digitação

<!DOCTYPE html>
<html>
<head>
    <title>Validação de Html</title>
    <meta charset="utf-8">
</head>
<body>

    <input name="nome" type="text" onkeypress="keyPressed(event)"/>

</body>
<script>
    function keyPressed(event){
        if(event.charCode >= 97 && event.charCode <= 122){
            // a-z --> Converter para A-Z
            return String.fromCharCode( event.charCode - 32 );
        }
    }
</script>
</html>