CAN_GetValue

PCAN-Basic

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PCAN-Basic Documentation

CAN_GetValue

Retrieves information from a PCAN Channel.

Syntax

C++

TPCANStatus __stdcall CAN_GetValue(
        TPCANHandle Channel,
        TPCANParameter Parameter,
        void* Buffer,
        WORD BufferLength
);

Parameters

Parameters	Description
Channel	The handle of a PCAN Channel (see TPCANHandle).
Parameter	The code of the information to be retrieved (see TPCANParameter).
Buffer	The buffer to return the required value.
BufferLength	The length in bytes of the given buffer.

Returns

The return value is a TPCANStatus code. PCAN_ERROR_OK is returned on success. The typical errors in case of failure are:

PCAN_ERROR_ILLPARAMVAL:	Indicates that the parameters passed to the function are invalid. Check the parameter 'Buffer'; it should point to a valid data container for the requested value.
PCAN_ERROR_INITIALIZE:	Indicates that the given PCAN channel was not found in the list of initialized channels of the calling application.
PCAN_ERROR_ILLPARAMTYPE:	Indicates that the requested information is not available for the given PCAN Channel. Check the value of 'Parameter'; some values are not available for all PCAN-Channels or cannot be read.

Remarks

Use the function CAN_GetValue to get information about PCAN environment as parameters like the Message Filter and values like the availability of a PCAN-Channel. Take in account that not all parameters are supported for all PCAN-Channels. The access's type of the parameters can also be different.

More information about the parameters and values that can be read can be found in Parameter Value Definitions.

Example

The following example shows the use of CAN_GetValue on the channel PCAN_USBBUS1 to check if the Message Filter is fully opened. In case of failure, the returned code will be translated to a text (according with the operating system language) in English, German, Italian, French or Spanish, and it will be shown to the user.

Note: It is assumed that the channel was already initialized.

C++:

int iBuffer;
TPCANStatus result;
char strMsg[256];

// The status of the message filter of the PCAN-USB Channel 1 is asked
//
result = CAN_GetValue(PCAN_USBBUS1, PCAN_MESSAGE_FILTER, &iBuffer, sizeof(iBuffer));
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
{
    // A text is shown giving information about the current status of the filter
    //
    switch(result != PCAN_ERROR_OK)
    {
        case PCAN_FILTER_OPEN:
            MessageBox("The message filter for the PCAN-USB, channel 1, is completely opened.");
            break;
        case PCAN_FILTER_CLOSE:
            MessageBox("The message filter for the PCAN-USB, channel 1, is closed.");
            break;
        case PCAN_FILTER_CUSTOM:
            MessageBox("The message filter for the PCAN-USB, channel 1, is custom configured.");
            break;
    }
}