JSFiddle - React, Tailwind, and code Playground

HTML

<span id="number"></span>

JavaScript

var buffer = new ArrayBuffer(20);
//first arguement-> reference to representing buffer
//second arguement-> offset
//third arguement-> size of typed array
var typed_array = new Uint8Array(buffer, 0);//created a typed array representing the complete ArrayBuffer

typed_array[0] = 1;
typed_array[9] = 4000;
alert(typed_array)
document.getElementById("number").innerHTML = typed_array[0];