ELF ORIENTED DEVICES AND NOT ELF ORIENTED DEVICES

2 types of devices can be handled:

1. ELF-oriented devices
2. NOT ELF-oriented devices

The ELF-oriented devices can only handle variables that are contained in the ELF file that characterizes them. The ELF file is a result of the compilation of application sw, is administered by the developers of this sw and can be made available to users.

The process of verification of consistency between the variables in the database and the variables retrievable from the ELF file, is called validation. A database that can not be validated can not perform the majority of communication operations.

The validation performed by ECT provides that:

• factory names (the names assigned to the variables in the application sw source) used in the database are actually present in the ELF file, which in turn corresponds exactly to the ECU application sw.
• attributes of the variables used in the device (size of the variable, array size, signed) correspond to what is stated in in the ELF and then in the application sw.

The validation will automatically assign the correct addresses for recognized variables. These addresses will be used for all communication operations.

In the configuration of a device-oriented ELF an identifying string is also specified. That string is used as a sw version signature during the communication. The string is read from ELF in the validation phase and permanently stored in the XML file. In the initial dialog between the ECU and ECT, ECT requires the identification string to the ECU and then compares this string with the identification string contained in the XML database of the device. If the strings match, ECT can ensure consistency between the ELF file used to validate the XML database and the application sw running in ECU. If unsuccessful, ECT can not communicate.

The ELF file is needed for the validation of the XML database of the device but after validation it is no longer necessary for ordinary tasks and there is no need to release the ELF file to the final user. The validation result is saved in the XML file and if no change is made to the content of the database, this result is valid even if the ELF file is missing. However, if the user wants to modify the device by adding new communication channels or new calibration variables, the ELF file must be available. An ELF file is available if is is located in a subfolder of [device_name].DEV called ELF. The full path to ELF [ECT_directory]\DEVICE\[device_name].DEV\ELF

The NOT ELF-oriented devices have no ability to check the validity of the addresses and size of the variables. The accuracy of the information contained in the device is derived only from checks on the sw sources owned by application sw developers.

In the NOT ELF-oriented devices, the address of the channels and other variables are specified in an indirect way through static table indexes. The real map of communication addresses shall be required by ECT to the ECU at the beginning of the communication session.