Interfacing PCAN USB using C++

[ganeshredcobra]

Hi,

Can i get a sample C++ code for loading PCANBasic dll, Initializing, sending and receiving CAN message. I am having PCANBasic.dll and PCANBasicCLR.h. In PCAN forum i found one simple C code is a there a C++ code for the same available. The example in the directory is associated with the User interface i am asking for a console app. The requirements will be PCAN USB, BAUD = 500 KBps, Send a message, read a message.

[K.Wagner]

Hello,

the code for sending/receiving CAN messages is the same, no matter if you are using a UI or not. Simple examples in C++ can be found in the help file. Look for the section "Example" in the help of the desired function (CAN_* in PCAN-Basic Documentation/Reference/Functions) :

Initialize a channel at 500K:

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TPCANStatus result;
char strMsg[256];

// The Plug & Play Channel (PCAN-USB) is initialized
//
result = CAN_Initialize(PCAN_USBBUS1,PCAN_BAUD_500K);
if(result != PCAN_ERROR_OK)
{
    // An error occurred, get a text describing the error and show it
    //
    CAN_GetErrorText(result, 0, strMsg);
    MessageBox(strMsg);
}
else
    MessageBox("PCAN-USB (Ch-1) was initialized");

Send a message:

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TPCANMsg msg;
TPCANStatus result;
char strMsg[256];

// A CAN message is configured
//
msg.ID = 0x100;
msg.MSGTYPE = PCAN_MESSAGE_STANDARD;
msg.LEN = 3;
msg.DATA[0] = 1;
msg.DATA[1] = 2;
msg.DATA[2] = 3;

// The message is sent using the PCAN-USB Channel 1
//
result = CAN_Write(PCAN_USBBUS1, &msg);
if(result != PCAN_ERROR_OK)
{
    // An error occurred, get a text describing the error and show it
    //
    CAN_GetErrorText(result, 0, strMsg);
    MessageBox(strMsg);
}
else
    MessageBox("Message sent successfully");

Read a message:

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TPCANMsg msg;
TPCANTimestamp timestamp;
TPCANStatus result;
char strMsg[256];

do
{
    // Check the receive queue for new messages
    //
    result = CAN_Read(PCAN_USBBUS1,&msg,&timestamp);
    if(result != PCAN_ERROR_QRCVEMPTY)
    {
        // Process the received message
        //
        MessageBox("A message was received");
        ProcessMessage(msg)
    }
    else
    {
        // An error occurred, get a text describing the error and show it
        // and handle the error
        //
        CAN_GetErrorText(result, 0, strMsg);
        MessageBox(strMsg);
        // Here can be decided if the loop has to be  terminated (eg. the bus
        // status is  bus-off)
        //
        HandleReadError(result);
    }
// Try to read a message from the receive queue of the PCAN-USB, Channel 1,
// until the queue is empty
//
}while((result & PCAN_ERROR_QRCVEMPTY) != PCAN_ERROR_QRCVEMPTY);

Put all three together and you have what you need.

NOTE: PCANBasicCLR.h is a header to be used only in managed environments (C++/CLR). For C++ you need to use PCANBasic.h

[ganeshredcobra]

Thank you, That worked fine.
While reading the CAN messages continuously and processing i am getting a lot of delay. When a value change happens in a message the effect comes on my code after some time, why is this happening? Do i need to clear any buffer i didn't see any other API calls other than

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PCAN_Read

.Is there any event triggered method other than polling.

An another query is regarding Filtering of messages.If i want to filter multiple messages which are not in order say i have to filter ten messages, is it OK call

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g_CAN_FilterMessages

ten times.

If i need to a filter a particular ID say 0x265, can i give the call like this.

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CANStatus = g_CAN_FilterMessages(g_hChannel, 0x265, 0x265, PCAN_MESSAGE_STANDARD);

the start and end of the sequence with same id.

[PEAK-Support]

please take a lock in the API description. There you will find all answers to your questions.
We also have a very good documented sample code that alsow shows all types of sending and receiving.
The Docu is part of the PCAN-Basic API package: LINK Please spend some time with study this document (Windows Help File)

[nadaanas1985]

Hi

I want to ask what's the header file I should include to use this C++ program. I tried but still getting errors in ProcessMessage function and HandleReadError. also I'm getting link2019 error in visual studio and that related o Can Read. I think I have to include not just PCANBasic.h. I'm using Peak- PCI, but I think I can use the same functions.

I need help please

Thank you

[K.Wagner]

Hello,

if you are using native C, or C++, then you have to use the header file PCANBasic.h
Otherwise, if oyu are using Visual C++/CLR (managed C++), then you need to include the file PCANBasicCLR.h

Note that you have project samples for both cases, so feel free to open them and check which one fits better for you.

[nadaanas1985]

Hi

Thank you for your reply K.Wagner. I'm using native C++. I've already include the header file PCANBasic.h in my program but the problem I'm still have this lnk2019 error (Error LNK2019 unresolved external symbol _CAN_Read@12 referenced in function _main

Error LNK2019 unresolved external symbol _CAN_Initialize@20
)

This is my program:

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#include "stdafx.h"
#include "iostream"
#include <stdlib.h>

#include "windows.h"
# include "PCANBasic.h"



//#define _WIN32_WINNT 0x0500

using namespace std;

int ProcessMessage(TPCANMsg msg) {
	return 0;
}

int HandleReadError(TPCANStatus result) {
	return 0;

}

int main()
{
	TPCANMsg msg;
	TPCANStatus result;
	char strMsg[256];
	TPCANTimestamp timestamp;


	// The Plug & Play Channel (PCAN-USB) is initialized
	//
	result = CAN_Initialize(PCAN_USBBUS1, PCAN_BAUD_500K);
	if (result != PCAN_ERROR_OK)
	{
		// An error occurred, get a text describing the error and show it
		//
		CAN_GetErrorText(result, 0, strMsg);
		std::wcout<<(strMsg);
	}
	else
		std::wcout<<("PCAN-USB (Ch-1) was initialized");
	// sending the message

	

	// A CAN message is configured
	//
	msg.ID = 0x701;
	msg.MSGTYPE = PCAN_MESSAGE_STANDARD;
	msg.LEN = 3;
	msg.DATA[0] = 1;
	msg.DATA[1] = 2;
	msg.DATA[2] = 3;

	// receiving the message



	do
	{
		// Check the receive queue for new messages
		//
		result = CAN_Read(PCAN_USBBUS1, &msg, &timestamp);
		if (result != PCAN_ERROR_QRCVEMPTY)
		{
			// Process the received message
			//
			std::wcout<<("A message was received");
			ProcessMessage(msg);
			
		}
		else
		{
			// An error occurred, get a text describing the error and show it
			// and handle the error
			//
			CAN_GetErrorText(result, 0, strMsg);
			std::wcout << (strMsg);
			// Here can be decided if the loop has to be  terminated (eg. the bus
			// status is  bus-off)
			//
			HandleReadError(result);
		}
		// Try to read a message from the receive queue of the PCAN-USB, Channel 1,
		// until the queue is empty
		//
	} while ((result & PCAN_ERROR_QRCVEMPTY) != PCAN_ERROR_QRCVEMPTY);

    return 0;
}

I tried to search and solve my errors but I couldn't. I've already have a look to the samples but all of them is not a native C++.

Please, I need help.
Thank you

[K.Wagner]

Hello,

about my last post, I mean the C++/MFC example. This is not a simple native C++ example, though the use of the PCAN-Basic library in this project is the same as in a native C++ application.

Nevertheless, your problem is actually the linkage to the library. Did you use already DLLs within a C++ application? if not, then take a look here for more information: About Dynamic-Link Libraries.

If you deside to use the load-time dynamic linking, tehn you will find the needed *.lib files for each platform within the PCAN-Basic packages you have downloaded (32-Bit: Win32\VC_LIB, 64-Bit: x64\VC_LIB).

[nadaanas1985]

Thank you K.Wagner for your help and support.

[nadaanas1985]

Hi K.Wagner

I want to ask if you know what's the function of the ProcessMessage and HandleReadError in native c++. Do you know how to write these function in the simple c++.

Thank you