Question

我对nodejs全新，我一直在尝试与arduino和节点app进行通信。我的节点代码监听串口并将数据发送到page.Everything正常但是发生了一个奇怪的情况。

var cleanData = ''; // this stores the clean data
var readData = '';  // this stores the buffer
sp.on("open", function () {
      console.log('open serial communication');
      });
         // Listens to incoming data
sp.on('data', function (data) { // call back when data is received
        readData += data.toString(); // append data to buffer
        // as clean data. Then clear the buffer. 
        if (readData.indexOf('B') >= 0){
            cleanData = readData.substring(readData.indexOf('B')+1,readData.length);
            console.log(cleanData);
            readData = '';

            //io.sockets.emit('pulse', cleanData);
        }

    });

以'B'开头的数据应该打印但是当我运行代码时，我看到了

喜欢这些。为什么打印'Q'的数据？

Answer 1

您也可以拆分换行，例如;

sp.on('data', function (data) {          // Call back when data is received

    readData += data.toString();         // Append data to buffer

    while(readData.indexOf('\n') > 0) {  // Process all full rows

      // Get everything before the line feed
      var cleanData = readData.substring(0, readData.indexOf('\n'));

      // ...and remove what we just extracted from the read buffer
      readData = readData.substring(readData.indexOf('\n') + 1, readData.length);

      // If it contains a B, well... you know what to do
      if(cleanData.indexOf('B') > 0) {
        console.log(cleanData);
        //io.sockets.emit('pulse', cleanData);
      }
    }
});

如果情况如此，nodejs很奇怪

1 个答案: