Purpose

Executes the UDS ReadDataByIdentifier service. Reads an ECU data record.

Format 

        long ndUDSReadDataByIdentifier(
       TD1 *diagRef,
       unsigned short ID,
       unsigned char dataOut[],
       long *len,
       LVBoolean *success);

Input

diagRef

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

ID

Defines the identifier of the data to be read. The values are application specific. Output

dataOut

Returns the ECU data record. If you know the record data description, use ndConvertToPhys to interpret this record.

len

On input, len must contain the dataOut array length. On return, it contains the number of valid data bytes in the dataOut array.

success

Indicates successful receipt of a positive response message for this diagnostic service.

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

This function requests data record values from the ECU identified by the ID parameter.

For further details about this service, refer to the ISO 15765-3 standard.