Java串口写/发送ASCII数据 [英] Java serial port write/send ASCII data
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问题描述
我的问题是我需要通过蓝牙在Java中控制移动机器人E-puck，通过发送命令如D，100,100来设置速度，E以获得速度等等。我有一些代码：
My problem is that I need to control mobile robot E-puck via Bluetooth in Java, by sending it commands like "D,100,100" to set speed, "E" to get speed, and etc. I have some code:
String command = "D,100,100";
OutputStream mOutputToPort = serialPort.getOutputStream();
mOutputToPort.write(command.getBytes());
所以用这个方法写我只能这样做发送 byte [] 数据，但我的机器人不会理解。
例如以前我一直在Matlab上使用这个命令：
So with this method write I can only send byte[] data, but my robot won't understand that.
For example previously I have been using this commands on Matlab like that:
s = serial('COM45');
fopen(s);
fprintf(s,'D,100,100','async');
或仅限于程序Putty类型：
Or on program Putty type only:
D,100,100 `enter`
其他信息：
我也想通了，Matlab还有另一个解决方案。
I've also figured out, that Matlab has another solution for same thing.
s = serial('COM45');
fopen(s);
data=[typecast(int8('-D'),'int8') typecast(int16(500),'int8') typecast(int16(500),'int8')];
在这种情况下：
data = [ -68 -12 1 -12 1];
fwrite(s,data,'int8','async');
在Java中不一样：
byte data[] = new byte[5];
data[0] = -'D';
data[1] = (byte)(500 & 0xFF);
data[2] = (byte)(500 >> 8);
data[3] = (byte)(500 & 0xFF);
data[4] = (byte)(500>> 8);
然后：
OutputStream mOutputToPort = serialPort.getOutputStream();
mOutputToPort.write(data);
mOutputToPort.flush();
推荐答案
代码注释中的主要细节。现在，您可以通过在命令窗口 D，1000，-500 中键入并按下回车来更改车轮速度。
Main details in code comments. Now you can change wheel speed by typing in command window D,1000,-500 and hitting enter.
public class serialRobot {
public static void main(String[] s) {
SerialPort serialPort = null;
try {
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier("COM71");
if (portIdentifier.isCurrentlyOwned()) {
System.out.println("Port in use!");
} else {
System.out.println(portIdentifier.getName());
serialPort = (SerialPort) portIdentifier.open(
"ListPortClass", 300);
int b = serialPort.getBaudRate();
System.out.println(Integer.toString(b));
serialPort.setSerialPortParams(115200, SerialPort.DATABITS_8,
SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
serialPort.setInputBufferSize(65536);
serialPort.setOutputBufferSize(4096);
System.out.println("Opened " + portIdentifier.getName());
OutputStream mOutputToPort = serialPort.getOutputStream();
InputStream mInputFromPort = serialPort.getInputStream();
PerpetualThread t = readAndPrint(mInputFromPort);
inputAndSend(mOutputToPort);
t.stopRunning();
mOutputToPort.close();
mInputFromPort.close();
}
} catch (IOException ex) {
System.out.println("IOException : " + ex.getMessage());
} catch (UnsupportedCommOperationException ex) {
System.out.println("UnsupportedCommOperationException : " + ex.getMessage());
} catch (NoSuchPortException ex) {
System.out.println("NoSuchPortException : " + ex.getMessage());
} catch (PortInUseException ex) {
System.out.println("PortInUseException : " + ex.getMessage());
} finally {
if(serialPort != null) {
serialPort.close();
}
}
}
private static PerpetualThread readAndPrint(InputStream in) {
final BufferedInputStream b = new BufferedInputStream(in);
PerpetualThread thread = new PerpetualThread() {
@Override
public void run() {
byte[] data = new byte[16];
int len = 0;
for(;isRunning();) {
try {
len = b.read(data);
} catch (IOException e) {
e.printStackTrace();
}
if(len > 0) {
System.out.print(new String(data, 0, len));
}
}
}
};
thread.start();
return thread;
}
private static void inputAndSend(OutputStream out) {
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
int k = 0;
for(;;) {
String komanda;
try {
komanda = in.readLine();
} catch (IOException e) {
e.printStackTrace();
return;
}
komanda = komanda.trim();
if(komanda.equalsIgnoreCase("end")) return;
byte komandaSiust[] = proces(komanda); //Command we send after first
//connection, it's byte array where 0 member is the letter that describes type of command, next two members
// is about left wheel speed, and the last two - right wheel speed.
try {
if(k == 0){
String siunc = "P,0,0\n"; // This command must be sent first time, when robot is connected, otherwise other commands won't work
ByteBuffer bb = ByteBuffer.wrap(siunc.getBytes("UTF-8"));
bb.order(ByteOrder.LITTLE_ENDIAN);
out.write(bb.array());
out.flush();
}else{
ByteBuffer bb = ByteBuffer.wrap(komandaSiust);
bb.order(ByteOrder.LITTLE_ENDIAN);
out.write(bb.array());
out.flush();
}
k++;
} catch (IOException e) {
e.printStackTrace();
return;
}
}
}
private static byte[] proces(String tekstas){
tekstas = tekstas.trim();
char[] charArray = tekstas.toCharArray();
byte kodas1[];
int fComa = tekstas.indexOf(',', 1);
int sComa = tekstas.indexOf(',', 2);
int matavimas = charArray.length;
int skir1 = sComa - fComa - 1;
int skir2 = matavimas - sComa -1;
char leftSpeed[] = new char[skir1];
for(int i = 0; i < skir1; i++){
leftSpeed[i] = charArray[fComa + i + 1];
}
char rightSpeed[] = new char[skir2];
for(int i = 0; i < skir2; i++){
rightSpeed[i] = charArray[sComa + i + 1];
}
String right = String.valueOf(rightSpeed);
String left = String.valueOf(leftSpeed);
int val1 = Integer.parseInt(left);
int val2 = Integer.parseInt(right);
kodas1 = new byte[5];
kodas1[0] = (byte)-charArray[0];
kodas1[1] = (byte)(val1 & 0xFF);
kodas1[2] = (byte)(val1 >> 8);
kodas1[3] = (byte)(val2 & 0xFF);
kodas1[4] = (byte)(val2 >> 8);
return kodas1;
}
private static class PerpetualThread extends Thread {
private boolean isRunning = true;
public boolean isRunning() { return isRunning; }
public void stopRunning() {
isRunning = false;
this.interrupt();
}
}
}
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