Range of Measurement in A2L File for the ECU Measurement and Calibration Toolkit

Updated Dec 22, 2023

Reported In

Software

  • ECU Measurement and Calibration Toolkit

Issue Details

When using the ECU Measurement and Calibration Toolkit to measure and calibrate an electronic control unit (ECU), how is data outside the expected range handled?

Solution

In the following, how the ECU Measurement and Calibration Toolkit uses (.A2L) database files to measure the ECU is explained.

The (.A2L) file contain information on the measurement calibration and event definitions used for acquiring and simulating data from an ECU.

The ranges for used for measuring the data from an ECU is given by a .A2L file, this defines a table which is used for the conversion of data. For example, in the A2L file given in the LabVIEW example CCPECU.A2L (see C:\Program Files (x86)\National Instruments\LabVIEW 20xx\examples\ECUMC), the following conversion table is given:
 
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If the measured data in the XCP command is out of range, then the default output is returned as specified in the .A2L file by the "DEFAULT_VALUE" (string) or "DEFAULT_VALUE_NUMERIC" (float value).

Additional Information

To make use of the powerful testing and verification framework of VeriStand, this software can be used with the ECU by using the ECU Measurement and Calibration Toolkit  with the XCP/CCP Master Custom Device. In this case, VeriStand also uses the default output as defined by the .A2L file

MC Text To Double.vi performs the conversion from the text input value into a double value. You can use this especially if the measurement or characteristic has an associated enumeration or range text type scaling before writing the double values to the ECU, using the regular write VIs.