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我可以使用我的 Web 应用程序通过 Modbus 寻址设备。在这种情况下，寻址意味着发送 Modbus 命令并接收响应。

但是，如果不关闭浏览器并重新启动页面，我将无法重复该过程。

我现在的具体问题是如何调整代码以永久重新发送相同的 modbus 命令？因此，您将按下按钮，而不是在控制台中出现单个响应，而是在响应出现后出现另一个响应并出现另一个响应......

谢谢你的帮助。

<!DOCTYPE html>
<html lang="de">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>examplepage</title>
    <script>
        
    async function start() 
    {
            // Prompt user to select any serial port.
            const port = await navigator.serial.requestPort();

            // Wait for the serial port to open.
            await port.open({ baudRate: 9600, dataBits: 8,  stopBits: 2, ParityType: "none"});

            //Übermittle Anfrage um Inhalt von Register anzufordern
            const writer = port.writable.getWriter();

            //const data = new Uint8Array([0x01, 0x03, 0x00, 0x01, 0x00, 0x02, 0x95, 0xCB]); // request for register
            const data = new Uint8Array([0x01, 0x03, 0x00, 0x37, 0x00, 0x02, 0x75, 0xC5]);
            await writer.write(data);


            // Allow the serial port to be closed later.
            writer.releaseLock();
            // empfangen
            const reader = port.readable.getReader();

            // Listen to data coming from the serial device.
            while (true) {
            const { value, done } = await reader.read();
            if (done) {
                // Allow the serial port to be closed later.
                reader.releaseLock();
                break;
            }
            // value is a Uint8Array.
            console.log(value);
            }
    }
    
    if ("serial" in navigator) {
  alert("Your browser supports Web Serial API!");
}
    else {alert("Your browser does not support Web Serial API, the latest version of Google Chrome is recommended!");};
    
    </script>
  </head>
  <body>
   <button onclick="start()">Click me</button> 
  </body>
</html>

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