C / C++ / MFC

serial port communication in embedded visual c++

6-Apr-06 10:36

Troposphere wrote:
...but if the int held the value 356, would the char take on the value 128 since 128 is the highest number a char can hold?

No, it would "wrap" all the way back around to (positive) 100. The leftmost 16 bits would go away. A better example would be if the int value was something like 200. The resulting char value would be -56. The leftmost 16 bits still go away, but now the sign bit is 1, indicating a negative.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

neha_vi216-Apr-06 8:30

neha_vi21

6-Apr-06 8:30

I am not able to read & write to serial port in WINDOWS CE using embedded visual c++. i am including the code i have tried.it showing no.of bytes written as 1 but while reading it is showing as no.of bytes read as 0.

//writing
DWORD dwError,dwNumBytesWritten;
int rc;
HANDLE hPort;
BYTE B;
TCHAR* pFileName = TEXT("COM1:");
B='a';

hPort =CreateFile(pFileName,GENERIC_READ| GENERIC_WRITE,0,NULL,OPEN_EXISTING,0,NULL);
rc=WriteFile (hPort,&B,1,&dwNumBytesWritten,NULL);
CloseHandle (hPort);

//reading
DWORD dwError,dwNumBytesRead;
int rc;
HANDLE hPort;
BYTE B;
TCHAR* pFileName = TEXT("COM2:");

hPort =CreateFile(pFileName,GENERIC_READ| GENERIC_WRITE,0,NULL,OPEN_EXISTING,0,NULL);
rc=ReadFile (hPort,&B,1,&dwNumBytesRead,NULL);
MessageBox(NULL,TEXT(""+B),NULL,MB_OK);
CloseHandle (hPort);

can anyone please halp me

Thanks for your reply in advance.

Neha

Newbie question

cdengler6-Apr-06 8:24

cdengler

6-Apr-06 8:24

I'm looking for a quick template or sample code to write a quick "installer" type program in (not managed) C++ to install items to the PROGRAMS folder that simply are links to a website.

For example, START / ALL PROGRAMS / MY FOLDER / Link 1, Link 2, etc.

Does anyone have anything like this?

Re: Newbie question

David Crow6-Apr-06 10:42

Toolbar border in dialog question

6-Apr-06 10:42

See here and here.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

Re: Newbie question

Richard Andrew x646-Apr-06 11:45

Richard Andrew x64

6-Apr-06 11:45

A link to CodeGuru?!! Blasphemy!!

Cpt Rick6-Apr-06 8:24

Cpt Rick

6-Apr-06 8:24

I'm using toolbars in a couple dialogs (actually property pages). I can get them transparent by setting that in OnErase in the derived CToolbar class, but I always get a border on the top.

I've played around with the flags to try and get rid of that top border, no luck, and I think I've forgotten everything I've tried at this point - brain fry Smile | :)

CTooltipCtrl for a modeless dialog in a DLL

madmax00016-Apr-06 7:49

madmax0001

6-Apr-06 7:49

Hi, me again...

a few days a go I posted a problem with showing tooltips in a modeless dialog in a dll. I got a hint which seems to solve the problem.
I have done several tests in the meantime and unfortunatelly there is still a small problem with the tooltip.
To setup the tooltips for the modeless dialog in my dll I use this function:
//////////////////////////////////////////
void CMyDialog::SetToolTip(CWnd* pWnd, LPCTSTR lpszText)
{
if((pWnd != NULL) && (m_pTip != NULL)){
TOOLINFO ti;
ti.cbSize = sizeof(TOOLINFO);
ti.lpszText = (LPTSTR)lpszText;
ti.hinst = AfxGetInstanceHandle();
ti.hwnd = pWnd->m_hWnd;
ti.uFlags = TTF_SUBCLASS | TTF_IDISHWND;
ti.uId = (UINT)pWnd->m_hWnd;
m_pTip->SendMessage(TTM_ADDTOOL, 0, (LPARAM)&ti);
}
}
//////////////////////////////////////////

THe tooltip is shown and this works without (!) any call to CMyDialog::PreTranslateMessage(MSG* pMsg) and RelayEvent. But I need this call, because there is an MFC bug with tooltips for disabled controls and I used in my other modal dialogs this code:

//////////////////////////////////////////
BOOL CMyDialog::PreTranslateMessage(MSG* pMsg)
{
TRACE("PreTranslateMessage\n");

if(m_pTip != NULL){
// The following code is a workaround for a MFC tooltip bug which
// prevents the popup of a tooltip for a disabled control in a modal dialog.

// Transate the message based on TTM_WINDOWFROMPOINT
MSG msg = *pMsg;
msg.hwnd = (HWND)m_pTip->SendMessage(TTM_WINDOWFROMPOINT, 0, (LPARAM)&msg.pt);
CPoint pt = pMsg->pt;
if((msg.message >= WM_MOUSEFIRST) && (msg.message <= WM_MOUSELAST))
::ScreenToClient(msg.hwnd, &pt);
msg.lParam = MAKELONG(pt.x, pt.y);

// Let the ToolTip process this message.
m_pTip->RelayEvent(&msg);
} // if
return CDialog::PreTranslateMessage(pMsg);
}
//////////////////////////////////////////

Then I tried to use the message hook which was neccessary to use accellerators in CMyDialog to call PreTranslateMessage:

//////////////////////////////////////////
// Hook procedure for WH_GETMESSAGE hook type.
LRESULT CALLBACK GetMessageProc(int nCode, WPARAM wParam, LPARAM lParam)
// If this is a keystrokes message, translate it in controls'
// PreTranslateMessage().
LPMSG lpMsg = (LPMSG)lParam;

if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_KEYFIRST && lpMsg->message <= WM_KEYLAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){
// The value returned from this hookproc is ignored, and it cannot
// be used to tell Windows the message has been handled. To avoid
// further processing, convert the message to WM_NULL before
// returning.
lpMsg->message = WM_NULL;
lpMsg->lParam = 0L;
lpMsg->wParam = 0;
}

// Process WM_MOUSE messages for tooltips here ????
if((nCode >= 0) &&
(PM_REMOVE == wParam) &&
(lpMsg->message >= WM_MOUSEFIRST && lpMsg->message <= WM_MOUSELAST) &&
(AfxGetApp()->PreTranslateMessage((LPMSG)lParam)) == TRUE){

// Do nothing ???

}
// Passes the hook information to the next hook procedure in
// the current hook chain.
return ::CallNextHookEx(g_hHook, nCode, wParam, lParam);
}
//////////////////////////////////////////

When I use the above code the tooltips for disabled controls work, but something with the mousemessage handling is wrong, because CCombobox controls can't be opened (They open very short and automatically close again).

Does anyone know how to solve my problem?? I think somehow I must call RelayEvent of the tooltip.

THX

Interesting Windows Architecture Questions

Richard Andrew x646-Apr-06 7:47

Richard Andrew x64

6-Apr-06 7:47

Is it safe to say that every user-mode process is a child of either the Services Controller (services.exe) or the Shell (explorer.exe) ??

Does the User32::ShellExecute function ultimately resolve to a call to CreateProcess, or does ShellExecute ultimately create the given process with calls to native functions??

PropertyPage Help

NYTSX6-Apr-06 7:28

6-Apr-06 7:28

I have an edit box on my property page that I want to check to make sure the user is putting the proper data in. In order to do this I use OnKillFocus() and set the focus back to edit box which has a problem. This works fine.

My problem is that when I switch to a different page on my property sheet, it does not keep the previous page up front. I still get the message box that I throw for errors, but the page still becomes inactive. I tried to use a ShowWindow(SW_SHOWNORMAL) but it looks like the new tab is still selected even though it show the contents of the previous tab.

Thanks in advance!

David Crow6-Apr-06 7:42

6-Apr-06 7:42

In the OnKillActive() method, what value are you returning?

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

NYTSX6-Apr-06 7:55

6-Apr-06 7:55

that method returns a void. All I really do is throw a MessageBox("Error") message in there.

David Crow6-Apr-06 8:17

6-Apr-06 8:17

NYTSX wrote:
that method returns a void.

For a window/control, yes. OnKillActive() should return non-zero if losing focus is allowed, 0 otherwise.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

NYTSX6-Apr-06 8:27

6-Apr-06 8:27

OK, maybe I am really unclear.

I am using the OnKillFocus() for an EditBox. My problem is that when I switch tabs, it throws the error but still allows for the tab to be changed. I ideally would like for the tab not to be switched at all.

Thanks for all your help.

David Crow6-Apr-06 8:35

6-Apr-06 8:35

NYTSX wrote:
I ideally would like for the tab not to be switched at all.

Which is why I suggested overriding OnKillActive().

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

NYTSX6-Apr-06 9:41

6-Apr-06 9:41

I was trying to do use SetActiveWindow() and/or ShowWindow() in the OnKillActive() and neither do what I want. Should I be doing something else?

Thanks for being so patient!

David Crow6-Apr-06 10:38

lord of the sockets please help

6-Apr-06 10:38

NYTSX wrote:
I was trying to do use SetActiveWindow() and/or ShowWindow() in the OnKillActive() and neither do what I want.

There's no need to do any of that. Simply return 0 from OnKillActive() if you do not want the tab to change. A value of 1, which is the default, will allow the tab to be changed.

"Let us be thankful for the fools. But for them the rest of us could not succeed." - Mark Twain

"There is no death, only a change of worlds." - Native American Proverb

nahitan6-Apr-06 7:26

nahitan

6-Apr-06 7:26

How to define and use 3 sockets which should be always open to 3 different locations and work as TCP/IP listening and sending messages which come in XML format like <start><id>id<id><name>name<name>.... Do I have to write three different socket class?
Thanks,

nahitan

Re: lord of the sockets please help

Richard Andrew x646-Apr-06 8:00

Richard Andrew x64

6-Apr-06 8:00

I'm no Lord of Sockets, but I can tell you that if you want to have continuous connections to 3 different hosts, then you will need 3 separate sockets.

A TCP/IP socket does not know anything about XML. It is up to your program to interpret the XML. The only thing the socket does is send and receive packets of bytes.

Dialog based application with background

Rostfrei6-Apr-06 6:31

Rostfrei

6-Apr-06 6:31

Hello!

I make simple dialog based programs. I make them with resource editor VS.NET 2003. When I create dialog it is grey. After I put some other controls on it. What is the easiest way to make Dialog based application with some background of some predefined background (picture)? Instead of grey there would be some picture.

Best regards,

Rostfrei

Hamid_RT6-Apr-06 6:45

Hamid_RT

6-Apr-06 6:45

Hi Rostfrei ,
if you need to paint dialog use WM_CTLCOLOR
and if you want to draw picture I suggestion that use picture's in the WM_PAINT and the use handle dc

Hamid_RT6-Apr-06 6:52

Hamid_RT

6-Apr-06 6:52

include ->atlImage.h //in h file

CImage m_Image;//in h file

m_Image.Load("c:\\picture.bmp");//[in the OnInitDialog(example)]

in function Onpaint
CPaintDC dc(this); // device context for painting
m_Image.BitBlt(dc.m_hDC,CRect(0,0,800,600),CPoint(0,0));

Rostfrei6-Apr-06 7:45

Rostfrei

6-Apr-06 7:45

When I include atlImage.h

I get many errors like:

LIBCMTD.lib(dbgheap.obj) : error LNK2005: _malloc already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(dbgheap.obj) : error LNK2005: _free already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(crt0dat.obj) : error LNK2005: _exit already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(crt0dat.obj) : error LNK2005: __exit already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(crt0dat.obj) : error LNK2005: __cexit already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(crt0dat.obj) : error LNK2005: __c_exit already defined in msvcrtd.lib(MSVCR71D.dll)
LIBCMTD.lib(crt0init.obj) : error LNK2005: ___xc_z already defined in msvcrtd.lib(cinitexe.obj)
and so on...

What shoild I do?

Rostfrei