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As Vaclav_Sal said (and me, yesterday): Parallel. You just need your 4 leds and a serial resistance for each LED (to limit the current through the LED).
A rule of thumb, for a red LED (with 1.6 Volts forward drop): Measure the voltage on a pin on the parallel port, when it is high.
Subtract that voltage with 1.6 (the forward voltage drop in the LED).
Divide the result by 0.01 (10 mA), and the value you get is the resistance value (in ohms) for the serial resistance.
If the LED doesn't light up enough (depends on the driver circuit), decrease the resistance.
You can use inpout32.dll to control the parallel port. You can download it here[^]
-- modified at 2:48 Thursday 10th May, 2007
Alcohol. The cause of, and the solution to, all of life's problems - Homer Simpson
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*Roxanna* wrote: ey guys, im wondering which is better, serial port or parallel port for connecting with 4 LEDs and using Microsoft Visual C++? hit me back yea guys asap, please...
much better to learn serial port programming.. as AFAIK Parallel port is obsolete now!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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i use these code to show table name (in a mdb file )in the list control, but there are some strange table name in the list?
CListCtrl m_table;
CDaoDatabase db;
db.Open("D:\\ktt.mdb");
short n_table=db.GetTableDefCount( );
CDaoTableDefInfo TableInfo;
for( int i=0; i{
db.GetTableDefInfo(i, TableInfo, AFX_DAO_PRIMARY_INFO );
m_table.InsertItem(0,TableInfo.m_strName);
}
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and your question is ...?
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How can I remove these extra tables in the list
Extra table names are: MsysRelationships, MsysQueries, MsysObjects,MSysACEs,MSysAccessObjects
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Do you want to remove these items of ListCtrl ?
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Try:
db.GetTableDefInfo(i, TableInfo, AFX_DAO_PRIMARY_INFO);
if ((TableInfo.m_lAttributes & dbSystemObject) == 0)
m_table.InsertItem(0, TableInfo.m_strName);
"A good athlete is the result of a good and worthy opponent." - David Crow
"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne
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Hi,
I have a byte array, this array is beeing populated very quickly with data. Right now I am taking the data in the byte array and writing it to the harddrive, but because the byte array is large it is filling up the hard drive quick. I can keep up with copying this data to hard drive but is there anyway that before I copy this to a file, that I can compres it without losing alot of time that I can still pick up the next bunch of data and do the same to it.
Thanks in advance.
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Please refer compression techniques here[^].
Regards,
Paresh.
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There is a program in console based (which is working fine), in that one DLL and some header files are provided in project's sub-directory, i noticed that header files are listed as external dependencies in file view pane.
Now i want to convert that to GUI based(dialog based),even if i am including DLL &LIB files when compiing,the compiler is showing an error 'undeclared identifier' near functions declared in DLL, and can u tell me how to sort out this & also how add external dependencies.
please reply and Thanks in advance
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l_d wrote: 'undeclared identifier' near functions declared in DLL,
Including the .lib file in your project tells the linker about the DLL exports. Similarly, you must have a .h header file that tells the compiler about the DLL exports.
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l_d wrote: Now i want to convert that to GUI based(dialog based),even if i am including DLL &LIB files when compiing,the compiler is showing an error 'undeclared identifier' near functions declared in DLL, and can u tell me how to sort out this & also how add external dependencie
is LoadLibarary and GetProcAddress is of any use!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
Support CRY- Child Relief and You
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Hi all,
I am quite new to VC++(win32). I have got an application which i want to convert to BORLAND C++(GUI).
Well first of all i am struggling in stepping over the code in VC++.
Well in .Net we use F10 and F11 for step over and step through but in VC++ i guess there is only F10 option i.e. Step over.
Now if i press F10 it doesnt step over to all the functions and all, the program only step over these 3 steps and complete the execution.
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd){
DialogBoxParam(hInstance, MAKEINTRESOURCE(IDD_DIALOGMAIN), NULL, DialogProc, 0);
return 0;
Now you might say to use break point ..well i tried that aswell. i placed break point over 2-3 functions of which i want to see what exactly is going on so after going through all these functions i get an error i.e. "There is no source code available from the current location."
So i guess i am doing something wrong here .Pls suggest me the right way to deal with win32 application.
Thanks
SS
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Software_Specialist wrote: i placed break point over 2-3 functions
I only see one function call in your posted code, and it's one you won't be able to step into
without a debug version of the operating system.
Once DialogBoxParam() is called the UI is in a modal loop.
To debug at that point you need breakpoint(s) in your DialogProc.
F11 has been step-into for as long as I can remember on VS (I forget the two "step" keys in
Borland).
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Mark Salsbery wrote: I only see one function call in your posted code
Mark Salsbery wrote: To debug at that point you need breakpoint(s) in your DialogProc
So as you said i placed breakpt over DialogProc Function i.e.
<br />
<br />
BOOL CALLBACK DialogProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam){<br />
<br />
int wmId, wmEvent;<br />
<br />
switch(uMsg){<br />
case WM_INITDIALOG:<br />
hWnd = hwndDlg;<br />
SetWindowText(GetDlgItem(hWnd, IDC_EXT), "TXT");<br />
CenterWindow(hwndDlg);<br />
return TRUE;<br />
case WM_COMMAND:<br />
wmId = LOWORD(wParam); <br />
wmEvent = HIWORD(wParam); <br />
<br />
switch(wmId){<br />
case IDOK:<br />
EndDialog(hwndDlg, IDOK);<br />
break;<br />
case IDCANCEL:<br />
EndDialog(hwndDlg, IDCANCEL);<br />
break;<br />
case IDC_BROWSEBMP:<br />
OnBrowseBmp();<br />
break;<br />
case IDC_BROWSEFILE:<br />
OnBrowseFile();<br />
break;<br />
case IDC_COMBIND:<br />
OnCombindYo();<br />
break;<br />
case IDC_BROWSECASEBMP:<br />
OnBrowseCaseBmp();<br />
break;<br />
case IDC_EXTRACT:<br />
OnExtract();<br />
break;<br />
}<br />
break;<br />
<br />
case WM_PAINT:<br />
<br />
break;<br />
}<br />
return FALSE;<br />
}<br />
When i place break pt over this function it always return FALSE and give me error saying "There is no source code available from the current location".
Now within this fucntiont there are calls to many other functions and which in turn calls to many others. So how can i step through whole application. Where should i place the break point as i also tried placing break pt over functions call with in DialogProc function but nothing seems to be working.
Mark Salsbery wrote: (I forget the two "step" keys in
Borland).
Its F7 and F8 in borland.
Mark Salsbery wrote: a debug version of the operating system.
I am not much sure about this.
Please help me out in understanding confusing VC++ 
Thanks
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This doesn't have much to do with the difference between Borland and VC.
Where to put breakpoints has to do with Windows message handling - this will be the same no matter
what development environment you use if you are using Win32 APIs.
First, make sure you are doing a debug build, not a release build of your application.
Then...
In your dialogproc, you can put a breakpoint:
1) switch(uMsg){
This will catch every message that goes to the dialog window
2) On any of the function calls.
When a breakpoint is hit you can step into the function with F11.
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Mark Salsbery wrote: make sure you are doing a debug build, not a release build of your application.
Yeh it is a debug build only well Debug is in selected mode in MS vs or is there any other way to check for debug mode then let me know if not then yes its in debug mode.
Both the option give me same error.
Mark Salsbery wrote: 1) switch(uMsg){
When cursor goes to next line it returns FALSE and then i get same error
Mark Salsbery wrote: On any of the function calls.
Nopes same error.
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Software_Specialist wrote: When cursor goes to next line it returns FALSE and then i get same error
At runtime? With a breakpoint on the switch statement?
Software_Specialist wrote: Both the option give me same error.
What kind of error??
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Mark Salsbery wrote: At runtime? With a breakpoint on the switch statement?
Yeh i placed break pt over switch(uMsg) and when cursor stops at dis pt then next jump it takes to return False and immidiately after crossing close bracket } it gives me error saying "There is no source code available for the current location."
Mark Salsbery wrote: What kind of error??
"There is no source code available for the current location."
I tried with another VC++ application aswell and it also gives me same kind of error. Ill try copying the code to new project and see if i face same problem or not.
Thanks
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Now i tried to re-build the application and it is giving me loads of errors like
Cannot convert parameter 2 from 'const char[6]'to'LPCWSTR'.
And many others similar to the above.
Well i guess this application is written in some older version of VC++ compiler and now when i tried to compile it over VS2005 i got a message saying
"The project 'abc.dsp' must be converted to the current Viusal C++ project format. After it has converted, you will not be able to edit this project in previous version of Visual Studio."
So what does this mean. Is the problem related to this.
Pls let me knw
Thanks
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Software_Specialist wrote: Now i tried to re-build the application and it is giving me loads of errors like
Cannot convert parameter 2 from 'const char[6]'to'LPCWSTR'.
Somehow you've changed the project settings to make a unicode build. If that's your intention
then you're going to have to fix your code to use Unicode.
Software_Specialist wrote: "The project 'abc.dsp' must be converted to the current Viusal C++ project format. After it has converted, you will not be able to edit this project in previous version of Visual Studio."
Make a backup of the old project - everything. Just in case you have to go back to the old VC
version. Then you can let the new VS convert the project to be compatible with the current
version.
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Software_Specialist wrote: Yeh i placed break pt over switch(uMsg) and when cursor stops at dis pt then next jump it takes to return False
That's because you'll get alot of messages in your DialogProc that you haven't handled in your
switch statement. A breakpoint there will stop on every message - there will be alot of them.
If you want to catch WM_INITDIALOG, then put a breakpoint at the code after "case WM_INITDIALOG:".
Software_Specialist wrote: "There is no source code available for the current location."
That's not an error. That means you are trying to step into code that doesn't have debug info
available to match up source code with machine code. In that case you can only step in via
the disassembly window.
There's nothing strange going on. You need breakpoints in YOUR code 
Mark
"Posting a VB.NET question in the C++ forum will end in tears." Chris Maunder
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Hi,
sometimes I can't use the debug breakpoints for A or B reason... When that happens... I use AfxMessageBox (...) / MessageBox (NULL,...).
You can not have lots of info, but at least you can determine when it chrashes by moving the message up and down (or with 2 or 3 and different messages). Once you know exactly WHERE, is easier to determine WHAT.
Greetings
--------
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
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Hello,
I'm receiving a windows message box (actual name of EXE omitted):
First-chance exception in ______.exe: 0xC0000005: Access Violation
Possible deallocation error? Any other ideas what the problem may be? Any help is appreciated. The disassembly code is shown below (crash at line 44).
38: void CPlex::FreeDataChain()
39: {
00479931 test ecx,ecx
00479933 je CPlex::FreeDataChain+15h (00479946)
00479935 push esi
40: CPlex* p = this;
41: while (p != NULL)
42: {
43: BYTE* bytes = (BYTE*) p;
44: CPlex* pNext = p->pNext;
<code>00479936 mov esi,dword ptr [ecx]</code>
45: delete[] bytes;
00479938 push ecx
00479939 call operator delete (0047f53d)
0047993E pop ecx
0047993F test esi,esi
46: p = pNext;
00479941 mov ecx,esi
00479943 jne CPlex::FreeDataChain+5 (00479936)
00479945 pop esi
47: }
48: }
Regards,
Mike
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Either the caller provied a bad this (but non-NULL) pointer or the linked list structure is corrupt.
Steve
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