Simple tool to generate the uints necessary for u8x8 drawtile: https://github.com/olikraus/u8g2/wiki/u8x8reference#drawtile - jsfiddle version: https://jsfiddle.net/hongm3tu/3/

DrawTile.html

<div id="main"></div>
<br/>
<button id="clear">Clear</button>
<button id="fill">Fill</button>
<button id="load">Load</button>
<br/>
<br/>
<textarea id="output"></textarea>

DrawTile.js

//for https://github.com/olikraus/u8g2/wiki/u8x8reference#drawtile
var main = document.getElementById("main");

var buttons = [];

for(var r = 0; r<8; r++)
{
  for(var c = 0; c<8; c++)
  {
  	(function()
    {
      var btn = document.createElement("BUTTON");  
			main.appendChild(btn);  
      buttons[r*8+c] = btn;
      
      btn.style.width = "30px";
      btn.style.height = "30px";

      btn.innerHTML = "&nbsp";    
      
      btn.isOn = false;
      
      btn.update = function()
      {
      	btn.style.backgroundColor = btn.isOn ? "black" : "white";
      }

			btn.update();

      btn.onclick = function()
      {
        btn.isOn = !btn.isOn;
        btn.update();
        doExport();
      };
    })();
    
	}
  
  var br = document.createElement("br");
  main.appendChild(br);
}

document.getElementById("output").style.width = "400px";
document.getElementById("output").style.height = "100px";

var doExport = function()
{
	var strings = [];
  
	for(var c = 0; c<8; c++)
  {
  	var total = 0;
    
    for(var r = 0; r<8; r++)
    {
    	if(buttons[r*8+c].isOn)
      {
      	total += Math.pow(2,r);
      }
    }
    
    strings.push("0x"+total.toString(16));
    //strings.push(total);
  }
	document.getElementById("output").value = strings.join(",");
};

document.getElementById("clear").onclick = function()
{
  for(var b = 0; b<8*8; b++)
  {
		buttons[b].isOn = false;
    buttons[b].update();
  }
  doExport();
}

document.getElementById("fill").onclick = function()
{
  for(var b = 0; b<8*8; b++)
  {
		buttons[b].isOn = true;
    buttons[b].update();
  }
  doExport();
}

document.getElementById("load").onclick = function()
{
  var input = document.getElementById("output").value;
  var parts = input.split(",");
  
  if(parts.length == 8)
  {
  	for(var c = 0; c<8; c++)
    {
  		var val = parseInt(parts[c],16);
      
      for(var r = 0; r<8; r++)
      {
      	buttons[r*8+c].isOn = ((val>>r) & 1) == 1;
        buttons[r*8+c].update();
      }
    }
  }
  
}

doExport();