Purpose

Establishes a connection channel to an ECU using the VW TP 2.0.

Format 

        long ndVWTPConnect(
      TD1 *diagRef,
      unsigned long channelID,
      unsigned char applicationType);

Input

diagRef

Specifies the diagnostic session handle, obtained from ndOpenDiagnosticOnCANFD and passed to subsequent diagnostic functions. Normally, it is not necessary to manually manipulate the elements of this struct.

channelID

Defines the CAN identifier on which the ECU responds for this connection. The ECU defines the ID on which the host transmits.

applicationType

Specifies the communication type that takes place on the communication channel. For diagnostic applications, specify KWP2000 (1). The other values are for manufacturer-specific purposes. Output

Return Value

The return value indicates the function call status as a signed 32-bit integer. Zero means the function executed successfully. A negative value specifies an error, which means the function did not perform the expected behavior. A positive value specifies a warning, which means the function performed as expected, but a condition arose that may require attention.

Use the ndStatusToString function to obtain a descriptive string for the return value.

Description

For the VW TP 2.0, you must establish a connection to the ECU before any diagnostic communication can occur. This function sets up a unique communication channel to an ECU that you can use in subsequent diagnostic service requests.

You must maintain the communication link thus created by periodically (at least once a second) calling ndVWTPConnectionTest.

No equivalent exists for the ISO TP (ISO 15765-2), as the ISO TP does not use a special communication link.