Question

我想在我的硬件系列api上运行命令

我使用这个开源代码 https://github.com/GoogleChrome/chrome-app-samples/tree/master/servo 这仅适用于整数

我想在串口中传递字符串，我的代码如下所示

 var connectionId = -1;

function setPosition(position) {
  var buffer = new ArrayBuffer(1);
  var uint8View = new Uint8Array(buffer);
  uint8View[0] = '0'.charCodeAt(0) + position;

  chrome.serial.write(connectionId, buffer, function() {});
};
function setTxt(data) {
 // document.getElementById('txt').innerHTML = data;
  var bf = str2ab(data)
  chrome.serial.write(connectionId, bf, function() {});
};
function str2ab(str) {
  len = str.length;
  var buf = new ArrayBuffer(len*2); // 2 bytes for each char
  var bufView = new Uint16Array(buf);
  for (var i=0, strLen=str.length; i<strLen; i++) {
    bufView[i] = str.charCodeAt(i);
  }

  return buf;
}
function onRead(readInfo) {
  var uint8View = new Uint8Array(readInfo.data);
 var value1 = String.fromCharCode(uint8View[0])
  var value = uint8View[0] - '0'.charCodeAt(0);
  var rotation = value * 18.0;
 // var dataarr = String.fromCharCode.apply(null, new Uint16Array(readInfo.data));
  //alert(rotation);
  if(uint8View[0])
  document.getElementById('txt').innerHTML = document.getElementById('txt').innerHTML + value1;
  document.getElementById('image').style.webkitTransform =
    'rotateZ(' + rotation + 'deg)';
//  document.getElementById('txt').innerHTML=uint8View[0];
  // Keep on reading.
  chrome.serial.read(connectionId, 1, onRead);
};
function ab2str(buf) {
  return String.fromCharCode.apply(null, new Uint16Array(buf));
}

function onOpen(openInfo) {
  connectionId = openInfo.connectionId;
  if (connectionId == -1) {
    setStatus('Could not open');
    return;
  }
  setStatus('Connected');

  setPosition(0);
  chrome.serial.read(connectionId, 1, onRead);
};

function setStatus(status) {
  document.getElementById('status').innerText = status;
}

function buildPortPicker(ports) {
  var eligiblePorts = ports.filter(function(port) {
    return !port.match(/[Bb]luetooth/);
  });

  var portPicker = document.getElementById('port-picker');
  eligiblePorts.forEach(function(port) {
    var portOption = document.createElement('option');
    portOption.value = portOption.innerText = port;
    portPicker.appendChild(portOption);
  });

  portPicker.onchange = function() {
    if (connectionId != -1) {
      chrome.serial.close(connectionId, openSelectedPort);
      return;
    }
    openSelectedPort();
  };
}

function openSelectedPort() {
  var portPicker = document.getElementById('port-picker');
  var selectedPort = portPicker.options[portPicker.selectedIndex].value;
  chrome.serial.open(selectedPort, onOpen);
}

onload = function() {
  var tv = document.getElementById('tv');
  navigator.webkitGetUserMedia(
      {video: true},
      function(stream) {
        tv.classList.add('working');
        document.getElementById('camera-output').src =
            webkitURL.createObjectURL(stream);
      },
      function() {
        tv.classList.add('broken');
      });

  document.getElementById('position-input').onchange = function() {
    setPosition(parseInt(this.value, 10));
  };
  document.getElementById('txt-input').onchange = function() {

    setTxt(this.value);
   // document.getElementById('txt').innerHTML = this.value;
  };
  chrome.serial.getPorts(function(ports) {
    buildPortPicker(ports)
    openSelectedPort();
  });
};

字符串是传递序列但是这个命令没有输入就按下如何操作任何人知道

提前感谢：）

Answer 1

在字符串

的末尾需要\n

示例：

writeSerial( '#;Bit_Test;*;1;' + '\n' );

看看这个项目http://www.dataino.it/help/document_tutorial.php?id=13

如何通过chrome serial api运行命令

1 个答案: