Digital Signature Verifier  is a tool that enables you to check whether the original file saved in the PLC has changed.

In Unistream there are several options to store Data Table to SD card by Store DTI To File function block.

The function block lists 4 options for saving:

While creating the file the system will create automatically a signature file for each CSV or UDTF file.

In case one we change the original CSV or UDTF file you can verify if the file was changed using the Digital Signature verifier.

To use the signature tool, both files must be in the same directory.

You can find this tool in UniLogic Tools menu >>Digital Signature Verifier:

Steps to use:

1. Place the CSV or UDTF file with its SIG file in the same directory

2. Open the Digital Signature Verifier

3. Click on browse and navigate to the directory with two files 

4. Click on Check Signature.

 In case the file was not changed: 

In case the file was changed: