Version Control with Git, GitHub and TIA Portal V21

Context and evolution in TIA Portal V21

In previous versions of TIA Portal it was already possible to integrate Git through Version Control Interface and add-ons such as VCI-VCS Connector. The previous series already covered how to prepare the environment, work with a local and remote repository, and recover versions: Part 1, Part 2 and Part 3.

The difference in this article is TIA Portal V21: SIMATIC Source Documents already existed for certain objects, such as LAD, DBs and PLC types, but Siemens extends its use to more languages, especially SCL, FBD and blocks with mixed languages. This allows more PLC logic to be represented through textual formats such as .s7dcl and .s7res, making comparison and versioning with Git easier.

The goal remains the same: traceability, comparison and recovery of PLC code changes. Instead of relying only on the TIA project binary file, the blocks are exported to a workspace with Version Control Interface and those files are versioned with Git.

TIA Portal V21 VCI / Workspace SIMATIC SD Git GitHub

Requirements

TIA Portal V21 with Version Control Interface available.
Git installed on Windows.
GitHub Desktop, optional but convenient for reviewing diffs, commits and push.
A GitHub account signed in to GitHub Desktop if a remote copy is required.
A dedicated local workspace folder, for example C:\PHS\TIA_GIT_TEST.

SIMATIC SD and VCI

SIMATIC Source Documents does not appear for the first time in V21: it is the textual format that TIA Portal can use to represent certain engineering objects outside the project. VCI exports blocks and types to files such as .s7dcl and, where applicable, .s7res. This allows Git to show line-by-line changes: new entries, modified conditions or removed logic.

TIA Portal V21 project with the Version Control Interface panel open

Initial VCI workspace configuration in TIA Portal

Prepare the workspace

From the project tree, add a new workspace under Version control interface and associate it with the local folder shared by TIA Portal and Git. In this example the folder is C:\PHS\TIA_GIT_TEST.

Export formats

In Configure workspace, under Export formats, select SIMATIC SD for the available languages and objects: LAD, FBD, SCL, data blocks and PLC data types. It is best to define this when the workspace is created.

Workspace export format options before selecting SIMATIC SD

Change the formats to SIMATIC SD.

With that configuration, VCI generates the files in the folder shared by TIA Portal and Git.

Files generated in the shared folder between TIA Portal and Git

First SCL FB exported

Program, save and compile the block. In the example, the motor FB in SCL is exported from VCI using Action: Export and Synchronize, taking advantage of the SIMATIC SD expansion in TIA Portal V21.

Motor block export from Version Control Interface

FB_Motor block exported into the workspace

When the directory is checked, the exported file is already there, for example FB_Motor.s7dcl.

Local directory with the exported FB_Motor file

First commit and publication

Local Git

Now move to Git. First, open PowerShell in the workspace folder.

$PowerShell opened in the C:\PHS\TIA_GIT_TEST folder$

         PowerShell
      

        cd C:\PHS\TIA_GIT_TEST
git init
git status
git add .
git commit -m "Version inicial FB_Motor"
git log --oneline
      

Initialize the repository and check the project status.

Git repository initialized and project status in PowerShell

Add all exported files and check that they are staged for the commit.

Git add and git status with exported files staged for commit

Create the first commit. If Git asks for identity, configure it once with git config --global user.name and git config --global user.email.

Check that the repository is on the master branch and that the working tree is clean.

Git status on master branch with no pending changes

GitHub Desktop

Then add the local repository in GitHub Desktop by selecting the same workspace folder.

Local repository opened in GitHub Desktop with the exported block

At this point the repository is local, so publish it from GitHub Desktop. For real projects it can be kept private.

Publish repository option in GitHub Desktop

The motor block is now published in GitHub.

GitHub repository with the published FB_Motor block

Changes, diff and history

Modify the FB

With the first version saved, modify the FB by adding one more variable and some logic.

FB_Motor modification with a new variable and additional logic

The project detects the change. In the workspace, the synchronization status of the objects is visible.

TIA Portal shows the modified block inside the project

Synchronization states between project and workspace in VCI

To make the workspace match the project, select Export again.

Export action in the workspace to synchronize the modified block

GitHub Desktop shows the change because it compares the exported file with the version that was already uploaded before.

Line-by-line diff of the FB_Motor block in GitHub Desktop

Commit, push and history

Create a commit with a clear comment, push it and check those changes in the history.

GitHub Desktop history with the block changes commit

Key points: VCI is not Git; VCI synchronizes TIA with external files and Git keeps the history. Export moves changes from TIA to the workspace; Import does the opposite. Commit saves a local version; Push sends it to GitHub.

Ladder block: workflow check

The Ladder test remains a practical check of the same system: when the block is exported through SIMATIC SD, VCI generates files that Git can detect and compare within the workflow.