Reliable online debugging

Reliable online debugging

The online debugger streams variable values and breakpoint events from the edge runtime, through the cloud, into the portal. The connection is designed to self-heal: a brief network blip will not lose your debug session, and reconnects happen automatically.

For the basics of viewing live values, see Online Values. This page covers the connection’s reliability behavior.

Starting a debug session

1. Open your project in the logiccloud IDE and select the Debug node in the project tree (the Debug entry in the IDE sidebar).
2. Select the debug-enabled device running your project from the device drop-down.
3. Wait for the session indicator to show Connected.

Note

Debug subscriptions retry automatically on transient errors, so it is normal for the session indicator to flicker briefly when the device is under heavy load.

What happens when the connection drops

1. The device/session indicator returns to Connecting… while the link is re-established.
2. The debugger reuses your existing selection once the connection is restored — you do not need to reconnect manually.
3. Variable values resume streaming as soon as the runtime acknowledges the resubscription.

When the session will not connect

1. Confirm the device is online on the device page.
2. Confirm the last installed build on the device matches the build you opened in the editor.
3. If the build identifiers differ, reinstall the build on the device before retrying the debug session.

Caution

Debugging requires the build running on the device to exactly match the build loaded in the portal. If you debug against a stale build, online values may bind to unexpected locations or fail to appear at all.