第一步
在head中写入meta
<head>
<meta charset="UTF-8" http-equiv="Refresh" content="1">
</head>第二步在head中写入函数
<head>
<meta charset="UTF-8" http-equiv="Refresh" content="1">
<script language="JavaScript">
function showtime(){
var now=new Date;
var str=now.toLocaleString();
document.getElementById("mytime").innerHTML="<font color='#f0ffff' style='font-size: 40pt'>"+str+"</font>"
}
</script>
</head>第三步body中写入div
<body >
<div id="mytime"></div>
</body>第四步在body中写入事件
<body bgcolor="#f5f5dc" onload="showtime()">
<div id="mytime"></div>
</body>
![[ESP32]：基于esp-modbus实现serial从机](https://img-blog.csdnimg.cn/direct/a2e95072f4f049339fc1eef7c9e9f84a.jpeg#pic_center)
