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Re: WritePrinter Fails to Print on Inkjet Printer

David Crow30-Sep-20 2:01

David Crow

30-Sep-20 2:01

As Esc/P is an older technology only supported by a few printers, have you considered using PCL instead?

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Re: WritePrinter Fails to Print on Inkjet Printer

sandford_j30-Sep-20 4:54

sandford_j

30-Sep-20 4:54

I did try to use PCL6 but fail.
I send the PCL command by calling WritePrinter API.
I do not know if I need to call another Win32 Printing API to send the PCL command.
The PCL command is arranged in an array of bytes. But, no response from the printer.
Any code sample to send PCL command, please?
Thank you.

Sandford

Re: WritePrinter Fails to Print on Inkjet Printer

Gerry Schmitz29-Sep-20 18:33

Gerry Schmitz

29-Sep-20 18:33

Installing the Epson Universal Print Driver -Windows

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

Re: WritePrinter Fails to Print on Inkjet Printer

sandford_j29-Sep-20 22:23

sandford_j

29-Sep-20 22:23

Hi Gerry,

Thanks. I will try.

Sandford

Re: WritePrinter Fails to Print on Inkjet Printer

mo149230-Sep-20 8:55

mo1492

30-Sep-20 8:55

Just a suggestion if you get really desperate; If the printer has a hex dump mode feature you can enable it and print out exactly what's being sent to the printer. Another way is to set the printer driver to 'Print to File' and your job will print to a file. Then if you are familiar with the printer language, you can examine the data to see if something has been added or missing in the printer data stream.
Good luck

Re: WritePrinter Fails to Print on Inkjet Printer

sandford_j30-Sep-20 12:05

sandford_j

30-Sep-20 12:05

Thanks.

Sandford

Re: WritePrinter Fails to Print on Inkjet Printer

mo14921-Oct-20 1:18

mo1492

1-Oct-20 1:18

I found some old code that I wrote some time ago but never tested. I did a quick test with it and found that when I printed to my hp laserjet that I was only getting 1/2 of the data. After a little investigating I found that i didn't adjust for unicode data so using "RAW" mode passing 2 * datasize to

WritePrinter((void*)data, 2*datasize, &dwBytesWritten)

seem to fix the problem. However, as I said, this code is not fully tested so don't know if this is a real fix or if it has anything to do with your problem. I have problem using "TEXT" mode also but don't feel like investigating. The documentation just says "size of the array". Doesn't mention anything about unicode.

Test data _T("abcd")
Sending a size of 4 resulted in "ab" printing out.
Sending a size of 8 resulted in "abcd" printing out.

Also, if your printer data escape sequence as nul values in it, you may have to adjust it for unicode; ie. double nul.
_T("escN") + nul + nul

Best regards.

-- modified 1-Oct-20 8:17am.

Re: WritePrinter Fails to Print on Inkjet Printer

sandford_j1-Oct-20 2:53

sandford_j

1-Oct-20 2:53

Noted. Thanks.

Sandford

Copying to ClipBoard By using SendInput, Failure....[Solved]

EuiyongYun28-Sep-20 14:37

EuiyongYun

28-Sep-20 14:37

Hi~
I wrote the following function to copy the selected part of NotePad.
( Sending Control+C Message )
However, it does not work!
Only 'C' is printed in NotePad.
Does anyone know why?

>> OS : Windows10
>> Compiler : VisualStudio 2010

C++

Send_KeyBoard_Control_C()
{
	HWND notepad = ::FindWindow(__T("NotePad"), NULL );
	if (notepad == NULL) {
		return;
	}
	if (!::SetForegroundWindow(notepad)) {
		return;
	}

	int sendCount = 0;
	INPUT input;

	// Press the "Ctrl" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = VK_CONTROL;
	input.ki.wScan = 0;
	input.ki.dwFlags = 0;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Press the "C" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wScan = 'C';
	input.ki.dwFlags = KEYEVENTF_UNICODE;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Release the "C" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wScan = 'C';
	input.ki.dwFlags = KEYEVENTF_UNICODE | KEYEVENTF_KEYUP;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Release the "Ctrl" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = VK_CONTROL;
	input.ki.wScan = 0;
	input.ki.dwFlags = KEYEVENTF_KEYUP;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	if ( sendCount != 4 ) {
		TRACE("fail\n");
	}
}

modified 30-Sep-20 6:56am.

Re: Copying to ClipBoard By using SendInput, Failure....

Victor Nijegorodov28-Sep-20 22:59

Victor Nijegorodov

28-Sep-20 22:59

Why are you using KEYEVENTF_UNICODE flag?

Re: Copying to ClipBoard By using SendInput, Failure....

EuiyongYun29-Sep-20 2:50

EuiyongYun

29-Sep-20 2:50

Thanks a lot!
I fixed it thanks to you.

C++

void Send_KeyBoard_Control_C()
{
	HWND notepad = ::FindWindow(__T("NotePad"), NULL );
	if (notepad == NULL) {
		return;
	}

	if (!::SetForegroundWindow(notepad)) {
		return;
	}

	int sendCount = 0;
	INPUT input;

	// Press the "Ctrl" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = VK_CONTROL;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Press the "C" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = 'C';
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Release the "C" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = 'C';
	input.ki.dwFlags = KEYEVENTF_KEYUP;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	// Release the "Ctrl" key
	ZeroMemory(&input, sizeof(INPUT));
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = VK_CONTROL;
	input.ki.dwFlags = KEYEVENTF_KEYUP;
	sendCount += SendInput(1, &input, sizeof(INPUT));

	if ( sendCount != 4 ) {
		TRACE("fail\n");
	}
}

Re: Copying to ClipBoard By using SendInput, Failure....

Victor Nijegorodov29-Sep-20 7:22

Victor Nijegorodov

29-Sep-20 7:22

How do I convert my C++ function pointer to a C function pointer?

arnold_w28-Sep-20 5:06

arnold_w

28-Sep-20 5:06

I am writing code for an ARM processor and compiling with GCC inside Eclipse IDE. When the application wants something to get done, it needs to create a task and queue it:

C++

typedef uint32_t (*task_t)(uint8_t* data, uint16_t dataSizeBytes);
void queueTask(task_t task, uint8_t* data, uint16_t dataSizeBytes);

Now I want to be able to queue C++ tasks inside the same task queue:

C++

#include <functional>
using namespace std;
using taskCpp_t = function <uint32_t(uint8_t* dataPtr, uint16_t dataSizeBytes)>;
void queueTaskCpp(taskCpp_t task, uint8_t* data, uint16_t dataSizeBytes);

The compiler complains when I simply try to cast my C++ function pointer into a C function pointer:

C++

void queueTaskCpp(taskCpp_t task, uint8_t* data, uint16_t dataSizeBytes) {
    queueTask((task_t)task, NULL, 0);  // Compiler complains!!!
}

Does anybody know what I can do to be able to queue taskCpp_t tasks into the same queue as the task_t are queued into?

Re: How do I convert my C++ function pointer to a C function pointer?

Richard MacCutchan28-Sep-20 5:54

Richard MacCutchan

28-Sep-20 5:54

I don't think you can. A C++ object cannot be used as a simple pointer as the two are totally different.

Re: How do I convert my C++ function pointer to a C function pointer?

CPallini28-Sep-20 6:07

CPallini

28-Sep-20 6:07

You may use a C++ static function as task. That would be equivalent to a standard C function.

Re: How do I convert my C++ function pointer to a C function pointer?

arnold_w28-Sep-20 7:33

arnold_w

28-Sep-20 7:33

I'm hoping to be able to use the function like this:

C++

queueTaskCpp([](uint8_t* data, uint16_t dataSizeBytes) {
    // My function implementation in PURE C (no C++) goes here...
}, NULL, 0);

I would assume the above function implementation would become static, right? God forbid if the function gets implemented on the stack, obviously that would mean I can't use this concept at all since the function implementation on the stack will most likely be corrupt when it's time to execute the queued function. I'm not planning to use any classes or object orientedness, I'm only using C++ to be able to pass anonymous functions like this.

Re: How do I convert my C++ function pointer to a C function pointer?

Mircea Neacsu28-Sep-20 6:14

Mircea Neacsu

28-Sep-20 6:14

To show how different the two things are try this:

C++

int main ()
{
  taskCpp_t t;
  cout << "taskCpp_t size: " << sizeof (taskCpp_t) << '\n';
  cout << "task_t size: " << sizeof (task_t) << '\n';
}

I get:

taskCpp_t size: 64
task_t size: 8

but it is up the compiler what a function object should contain.

Mircea

Embedded C program

Parth Akshay Barange22-Sep-20 22:27

Parth Akshay Barange

22-Sep-20 22:27

write an 8051 embedded c program in which after every 200 ms the leds connected to port 2 are turned on or off. assume xtal 11.0592mhz. use timer 0 in mode 1.

Re: Embedded C program

Graham Breach22-Sep-20 22:59

Graham Breach

22-Sep-20 22:59

I can't be bothered. You do it.

Re: Embedded C program

Richard MacCutchan22-Sep-20 23:40

Richard MacCutchan

22-Sep-20 23:40

Please read HOW TO ASK A QUESTION - C / C++ / MFC Discussion Boards[^]. As you can see there is no option for us to do your work.

Re: Embedded C program

CPallini23-Sep-20 1:12

CPallini

23-Sep-20 1:12

Start reading the 8051 datasheet (that you may find easily online) and your C compiler documentation (because you probably have to implement the timer 0 interrupt servicing routine).

Re: Embedded C program

Victor Nijegorodov23-Sep-20 8:42

Victor Nijegorodov

23-Sep-20 8:42

It seems to be a good idea. Good luck!

Re: Embedded C program

Dave Kreskowiak23-Sep-20 9:20

Dave Kreskowiak

23-Sep-20 9:20

Asking questions is a skill[^].
Seriously, if you want help from people, read that article.

Asking questions is a skill
CodeProject Forum Guidelines
Google: C# How to debug code
Seriously, go read these articles.

Dave Kreskowiak

Why isn't the copy constructor called

Mircea Neacsu22-Sep-20 14:59

Mircea Neacsu

22-Sep-20 14:59

I feel I'm turning slightly mad. In my mind the two variants below should give the same output:

C++

class A {
public:
  A () { cout << "A created" << endl; }
};

class B {
public:
  B () { cout << "Default B constructor" << endl; }
  B (A oa) { cout << "B created from A" << endl; }
  B (const B& other) { cout << "B copy constructor" << endl; }
};
int main()
{
  A aobj;
  B* bptr = new B (B (aobj));

  cout << "--------" << endl;

  B bobj (aobj);
  B* bbptr = new B (bobj);
}

After A is created, I create a B from A and then I copy the B using the copy constructor. At least that's my intention.

However the output I get is:

A created
B created from A
--------
B created from A
B copy constructor

What am I missing here?

Mircea

Re: Why isn't the copy constructor called

_Flaviu22-Sep-20 19:48

_Flaviu

22-Sep-20 19:48

I might be wrong, but

B (aobj)

from

new B (B (aobj))

should call move constructor, not copy constructor ...

P.S.

B (B (aobj))

would call a copy constructor only if what is inside of first brackets would be an already created B object, a l value, so, since

B (aobj)

is an anonymous object, move construct would be called.

P.P.S. I added move constructor to B

B(B&& rhs) { std::cout << "B move constructor" << std::endl; }

and is never called either.

modified 23-Sep-20 6:34am.

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