change value of input

Question

i'm trying to change the value of input element with javascript and i did it( based on console.log )but Input value doesn't display correct in html , any idea?

<h4 style="color: red; "> System is rebooting now ...
<br/><br/>Please Wait
<input type="text" name="n" value="30" style=" width: 30px ; height: 15px; " > s
<script type="text/javascript">
for (var i =29 ; i >=0; i--) {
document.getElementsByTagName('n').value=i; console.log(document.getElementsByTagName('n').value=i , i ); }
</script>
</h4>
</code>

Answer 1

no i wanted in this way obviously i did except a sleep function and not all await...
the other thing that i learnd is name and elementsbytagname not related its for input
even in that case its notworking and i have to use id for this =))
after 2 years =)
https://code.sololearn.com/WKEUMfqz77rU/?ref=app

Answer 2

<!-- i believe you wanted this... -->

<h4 style="color: red; "> System is rebooting now ...
<br/><br/>
Please Wait
<span id="n" value="30" style="width: 30px ; height: 15px; " >30</span> s
</h4>
<script>
var i = 30,
int = setInterval(function timed() {
document.getElementById('n').innerHTML = i;
if (!i--) {
clearInterval(int);
document.getElementById('n').innerHTML = "{ERROR! try again... :P}";
}
//console.log(document.getElementsByTagName('n').innerHTML, i);
}, 1000 /* change every 1 second */);
</script> <!-- after H4 !! -->