2017-04-22 217 views
0

我一直在尝试超过一个星期通过串行端口从树莓派(QT C++)到Arduino(Arduino IDE C++)进行通信,但我保持失败。Raspberry pi(QT C++)和Arduino(Arduino IDE)之间的通信

我在谷歌上做了一些搜索,看了一个例子......但仍然没有成功。好,所以基本的事情是我需要不断地将Raspberry pi的串口发送命令与Arduino进行通信。我尽量保持代码尽可能简单。

最初,我从树莓派(QT C++)发送“J”字符到Arduino(Arduino IDE C++)并等待J,使LED在Arduino上闪烁。但它不工作..即使我没有得到任何接口&通信&发送数据树莓pi(QT C++)到Arduino(Arduino IDE C++)的示例。我不知道究竟是什么问题。请帮助我解决问题。

在显示器,9600波特率

我重视程序是什么我已经在两侧尝试。

的main.cpp

#include <iostream> 
#include <QIODevice> 

#include <QtSerialPort/QSerialPort> 
#include <QtSerialPort/QSerialPortInfo> 
#include <QString> 

using namespace std; 

int main(int argc, char *argv[]) 
{ 
    QApplication a(argc, argv); 
    Dialog w; 
    w.show(); 

    QSerialPort serialPort; 
    serialPort.setBaudRate(QSerialPort::Baud9600); 

    QSerialPortInfo info("ttyUSB0"); 
     qDebug() << "Name  : "  << info.portName(); 
     qDebug() << "Description : "  << info.description(); 
     qDebug() << "Busy:"    << info.isBusy(); 

     QSerialPort serial; 
     serial.setPortName("ttyUSB0"); 

     serial.open(QIODevice::ReadWrite); 
     serial.setBaudRate(QSerialPort::Baud9600); 
     serial.setDataBits(QSerialPort::Data8); 
     serial.setParity(QSerialPort::NoParity); 
     serial.setStopBits(QSerialPort::OneStop); 
     serial.setFlowControl(QSerialPort::NoFlowControl); 

     serial.open(QSerialPort::ReadWrite); 
     cout<<"Readable :"<<serial.isReadable()<<endl; 
     cout<<"Writable :"<<serial.isWritable()<<endl<<endl; 

     if (serial.isOpen() && serial.isWritable()) 
     { 
      qDebug() << "Is open : " << serial.isOpen() << endl; 
      qDebug() << "Is writable : " << serial.isWritable() << endl; 

      qDebug() << "Ready..." << endl; 
      serial.write("J"); 

      QByteArray ba("J\n"); 

      serial.write(ba); 
      { 
       QByteArray ba("J"); 
       serial.write(ba); 
       serial.flush(); 
       qDebug() << "data has been send" << endl; 
       serial.close(); 
      } 
      if (serial.bytesToWrite() > 0) 
      { 
       serial.flush(); 
       if(serial.waitForBytesWritten(1000)) 
       { 
        qDebug() << "data has been send" << endl; 
       } 
      } 
      if(serial.flush()) 
       { 
        qDebug() << "ok" << endl; 
       } 
       qDebug() <<"value sent "<< endl; 
       serial.close(); 
     } 
     else 
     { 
      qDebug() << "An error occured" << endl; 
     } 
    return a.exec(); 
} 

Arduino的代码:

int led = 13, avlb = 0; 

void setup() 
{ 
Serial.begin(9600); 
pinMode(led, OUTPUT); 
Serial.println("started"); 
} 

void loop() 
{ 

if (Serial.available() > 0) 
{ 
    Serial.println("available"); 
    Serial.println(Serial.available()); 
    delay(2000); 
    digitalWrite(led, HIGH); 
    delay(5000);   

    if(Serial.read() == 'J') 
{ 
    Serial.println("read"); 
    Serial.println(Serial.read()); 
    delay(2000); 
    digitalWrite(led, LOW); 
    delay(1000); 
} 
} 

else 
{ 
    Serial.println("not available"); 
    delay(1000); 
} 
} 

输出显示:

树莓Qt创建者IDE O/P:

Name  : "ttyUSB0" 
Description : "FT232R USB UART" 
Busy: false 

Readable :1 
Writable :1 

Is open : true 

Is writable : true 

Ready... 

data has been send 

bool QSerialPort::flush(): device not open 
value sent 

Arduino的Ide的输出显示:

started 

not available 
not available 
not available 
not available 
not available 
not available 
not available 
not available 
not available 

回答

0

回答你的问题是,在下面的代码:

QByteArray ba("J"); 
serial.write(ba); 
serial.flush(); 
qDebug() << "data has been send" << endl; 
serial.close(); 

你让serial.flush()后,立即关闭端口。有必要等到数据真正发送完毕。例如,使用bool QSerialPort :: waitForBytesWritten (int msecs)