Going Online & Compare

When you go online with a PLC, AnyAutomation Studio opens an engineering connection to the controller CPU. This connection is for transferring and comparing engineering data — not for continuously watching live values. To read, write and watch individual tag values cyclically, use the Tag Browser in the PLCSim Advanced panel (see Hardware Simulation).

Going online / offline

Right-click a PLC in the project tree and choose Go Online from the context menu. A connection dialog opens (see below) where you pick the connection path and confirm with Go Online. Use the same right-click to disconnect again with Go Offline.

A status badge on the PLC shows the connection state — Online or Offline. It reflects only whether a connection exists.

The connection dialog

The dialog is modeled on TIA Portal's own go-online dialog:

• At the top, the Configured access nodes table lists the CPU's configured interfaces: device, slot, interface type, address and subnet. The table is for reference only and cannot be edited.
• Below it you pick the connection path: Type of the PG/PC interface (e.g. PN/IE), PG/PC interface (your network adapter, such as the PLCSIM virtual adapter) and Connection to interface/subnet (direct at a slot or via a subnet).
• The Address field takes the target IP. It is enabled when the connection goes via an address; with an invalid address the Go Online button stays disabled.
• Start Search scans for reachable devices on the selected interface and lists them. Clicking a result (or pressing Enter on it) adopts its address. On interfaces that connect directly at a slot, the search is unavailable and a hint in the dialog says so.
• Go Online connects; Cancel closes the dialog without going online.

The dialog remembers your last confirmed choice per PLC and preselects it the next time it opens. Reconnecting is usually a single click or Enter.

If connecting fails, a notification shows the error. Problems during the device search appear inside the dialog.

Per-block online/offline compare

As soon as the PLC is online, each block in the project tree shows a compare badge on the right that reconciles the offline state in the project against the online state on the CPU. The possible states are:

• Identical — the block's offline and online state match.
• Different — the block exists on both sides but differs.
• Offline only — the block is present in the project but missing online on the CPU.
• Online only — the block is present online on the CPU but missing from the project.

The comparison uses TIA Portal's own compare engine. The states shown therefore match exactly what TIA Portal's online/offline compare reports for the same PLC at the same moment.

Upload from Device (Compare)

The per-block compare badges only tell you that a block differs. To see what differs, upload the program from the controller and compare its content: right-click the PLC in the project tree and choose Upload from Device (Compare).

• The familiar connection dialog opens, titled for the upload. Pick the interface and target just as when going online and confirm with Upload.
• Studio reads the program from the running controller in the background. This takes a few minutes — a separate engineering instance starts in the background first. Progress is shown and the operation can be cancelled. If the PLC was online in Studio, it goes offline first.
• When the upload finishes, the comparison view opens automatically: every block, data type, tag table and technology object of the controller program is classified against your open project — changed, only in project, only on the controller, or unchanged. The header shows the source of the comparison. Activating a changed row opens a side-by-side diff of the project content versus the controller content.
• To adopt controller-state items into your project, check their rows and press Import Selected. The selected items are imported into your open project and the comparison refreshes afterwards.

If some items could not be read from the controller, a notice tells you so; they appear as "only in project" in the comparison. Know-how-protected blocks cannot be compared in content. The upload never writes to the controller, and your project only changes when you import.

Notes

• The engineering connection is not meant for continuously watching live values. Use the Tag Browser for that (see Hardware Simulation).
• The compare badges appear only while the PLC is online; they are not shown in the offline state.