串口如何稳定接收数据(转帖)

ohno

hi Vincent007,JohnYork

我已经把代码上传到如下链接，同时里面有一个测试视频，qt5.3.1 mingw编译的
http://pan.baidu.com/s/1kTh0ifd
。
谢谢你们的讨论。

ohno

hi Vincent007,JohnYork
你们是否看到代码？有问题吗？，有问题请留言谢谢.

Vincent007

試把
@
connect(
&m_Portconfigview,SIGNAL(signalConfigPort(const SPortsettings *)),&m_Serialportrecevie,SLOT(slotsConfigPort(const SPortsettings *)),Qt::QueuedConnection);
connect(
&m_Portconfigview,SIGNAL(signalConfigPort(const SPortsettings *)),this,SLOT(updatetstatus(const SPortsettings *)));
connect(
&m_Serialportrecevie,SIGNAL(signalThreadToStore( const QByteArray&)),&m_Serialportcachedata,SLOT(slotsSerialportcachedata(const QByteArray&)),Qt::BlockingQueuedConnection);
connect(
&m_Serialportcachedata,SIGNAL(signalToserialportwindow(const QByteArray&)),&m_pSerialPortWindow,SLOT(slotsserialportupdateview(const QByteArray&)),Qt::BlockingQueuedConnection);
@
改成
@
connect(
&m_Portconfigview,SIGNAL(signalConfigPort(const SPortsettings *)),&m_Serialportrecevie,SLOT(slotsConfigPort(const SPortsettings *)));
connect(
&m_Portconfigview,SIGNAL(signalConfigPort(const SPortsettings *)),this,SLOT(updatetstatus(const SPortsettings *)));
connect(
&m_Serialportrecevie,SIGNAL(signalThreadToStore( const QByteArray&)),&m_Serialportcachedata,SLOT(slotsSerialportcachedata(const QByteArray&)));
connect(
&m_Serialportcachedata,SIGNAL(signalToserialportwindow(const QByteArray&)),&m_pSerialPortWindow,SLOT(slotsserialportupdateview(const QByteArray&)));
@

ohno

hi Vincent007
我已经按照你说的进行测试，还是会卡住界面。谢谢。

Vincent007

Did you test release build?

ohno

hi Vincent007

1.我是用的release build。谢谢。
2.我看过java c# vc++写的类似串口调试助手都没有类似问题，qt版本网上所有的串口调试助手和qt官网自带的demo都有类似的问题。是不是qt控件本身的一个bug.

Vincent007

measure time consumed by slotsSerialportcachedata and slotsserialportupdateview via QElapsedTimer
另外你要確保你的PC 沒有問題.你有否在另一台PC試過你的程序?
@
QElapsedTimer timer;
timer.start();
slowOperation1();
qDebug() << "The slow operation took" << timer.nsecsElapsed() << "nanoseconds";
@

ohno

HI Vincent007
前阵子忙别的去，所以今天才回复你，不好意思按照你说的用以下代码进行测试
timer.start();
pSerialPortQPlainTextEdit.insertPlainText(DatatFormRead);
pSerialPortQPlainTextEdit.moveCursor(QTextCursor::End, QTextCursor::KeepAnchor);
qDebug() << "The slow operation took" << timer.nsecsElapsed() <<"nanoseconds";
下面是测试结果:
The slow operation took 1017500 nanoseconds
The slow operation took 1018310 nanoseconds
The slow operation took 1421502 nanoseconds
The slow operation took 1186476 nanoseconds

The slow operation took 10685984 nanoseconds
The slow operation took 10668154 nanoseconds
The slow operation took 10564419 nanoseconds
The slow operation took 10569686 nanoseconds
The slow operation took 10243486 nanoseconds
The slow operation took 10473245 nanoseconds
The slow operation took 10746766 nanoseconds
The slow operation took 10772700 nanoseconds
The slow operation took 10583059 nanoseconds
The slow operation took 11221681 nanoseconds
The slow operation took 10795798 nanoseconds
The slow operation took 16827051 nanoseconds

The slow operation took 222369451 nanoseconds
The slow operation took 205003460 nanoseconds
The slow operation took 222164411 nanoseconds
The slow operation took 204823949 nanoseconds
The slow operation took 209414655 nanoseconds
The slow operation took 186572559 nanoseconds
The slow operation took 209589304 nanoseconds
The slow operation took 214433676 nanoseconds
The slow operation took 219041401 nanoseconds
说明qt的窗口刷新确实有问题，请指教谢谢。

Vincent007

@
#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
_timer.setInterval(10);

for(int i = 0; i<1024;i++) {
    message += "1";
}
connect(&_timer,&QTimer::timeout,this,&MainWindow::updateText);
_timer.start();

}

MainWindow::~MainWindow()
{
delete ui;
}

void MainWindow::updateText()
{
ui->textEdit->append(message);
}
@
I did a simple application and test it. It works fine.
You can try it and adjust parameters.

ohno

HI Vincent007
我以前测试过调用append是没有问题的,建议你改成ui->textEdit->insertPlainText(message);试试。
因为我不能使用append,改成append会有这么一个问题
一句完整的话分2次发送过来就变成2行,比如:
“你好，谢谢你回答我的问题”。
分两次之后，有可能变成
“你好，”
“谢谢你回答我的问题”

blackRock

我发现MFC写的程序，会将多余的数据存储到硬盘，我用10ms的间隔，发送"hello"，MFC占用内存一直变化不大，但是QT却会随着时间增大，接收的数据一旦超过一屏能显示的量的话，马上就会变卡，是不是那个人写得换行代码的逻辑非常复杂低效果呢

blackRock

我发现MFC写的程序，会将多余的数据存储到硬盘，我用10ms的间隔，发送"hello"，MFC占用内存一直变化不大，但是QT却会随着时间增大，接收的数据一旦超过一屏能显示的量的话，马上就会变卡，是不是那个人写得换行代码的逻辑非常复杂低效果呢

blackRock

从2012到现在一直没什么改变

blackRock

从2012到现在一直没什么改变

ohno

HI blackRock blackRock
我也发现这个问题，但是不知道你是否遇到我类似的问题。

ohno

HI blackRock blackRock
我也发现这个问题，但是不知道你是否遇到我类似的问题。

Vincent007

I think you should ask this question on http://qt-project.org/forums/viewforum/10/
because more people will answer you.

Vincent007

I think you should ask this question on http://qt-project.org/forums/viewforum/10/
because more people will answer you.

blackRock

我跟你遇到的肯定是一样一样的

blackRock

我跟你遇到的肯定是一样一样的