Model Debug Messages


Overview

Model debug messages provide detailed information for diagnosing problems such as synchronization with the host and for repairing a malfunctioning model. They provide a review of a model interacting with a terminal datastream, allowing you to diagnose and repair screen recognition, data reads and/or writes, and synchronization flaws in a model. This feature is particularly helpful for those model designers working with VT hosts, where synchronization issues are more common.

A model debug message recording can be used for models under development in the Design Tool and for runtime models that have been deployed to the Host Integrator server.

You can have up to fifty model debug message recordings open at the same time. This allows you to compare model behavior under different circumstances or after you have made changes to the model.

Configuring model debug message recording mode

Model debug message recording is always enabled for models you open in the Design Tool. When testing your model within the Design Tool, you can configure the message recording level for the test server.

You can record deployed models on the Host Integrator server. You can configure the recording option as you deploy the model.

Model Debug Message Components

The model debug messages list

The left hand panel of the Model Debug Messages dialog box shows a list of the messages. The time-based list includes messages that have a subset or a series of nested subsets of additional messages, or descendants, associated with that action. Click the + symbol to view the message subset. These descendants typically display the underlying steps that transpired to produce the top level action.

Click an underlined link in a message to navigate to the entity in question. This option is not available when viewing a saved model debug message (.vmr) file when the model file is not present.

When you're viewing all messages (not datastream messages only), right-click a message for additional options:

Use the following symbols to manipulate the model debug messages list:

Symbol
Meaning
Display all messages.
Display datastream messages.

This option displays all messages that relate to the terminal exchanging data with the host, such as transmit, receive, and data processing messages. This option also displays entity arrival and departure, operation start and end, and errors associated with the datastream messages.

Display relative time for descendants.

By default, descendant messages associated with an action such as navigating to another entity are displayed with the time of the descendant message. Click this option to show relative time that elapsed relative to the action's start. This option helps identify abnormal delays associated with specific messages.

Find a message.

Click this option and type in a string to locate a specific message. You can also use the Find Message dialog box to find other occurrences of the messages, or to find messages of the same type as the selected message.

Find next error.

Click this button to locate the messages that are tagged as errors in the model debug messages list.

Clear all messages. (Actions that are in progress will not be cleared.)

Use this option when you are debugging a development version of a model and want to see the model's behavior after making some changes. You can save the previous collection of model debug messages before you use this option.

If you have opened a model debug message file other than the one associated with the current model, click to close the file.
Model debug message details

The right hand panel of the model debug message dialog box shows the details of the message highlighted on the left. Depending on what type of message is selected, it can include one or more of the following:

You can view all messages associated with the runtime model or focus on datastream messages only.

Datastream messages

Click the datastream messages icon to view datastream messages only in the model debug messages list.

When you select a datastream message (whether you're viewing all model debug messages or just datastream messages), select a message to see datastream details in the window at the lower right of the dialog box.

The datastream window

The datastream window displays the real-time data sent and received from a host. This information is particularly valuable when debugging datastream issues on a character mode host. You can copy and paste text from this window into the WaitForCommString command dialog box or the Host Communication String event dialog box to configure operations that include raw host communications. This window contains errors, and operations in addition to the datastream messages.

Without this window, it is difficult to determine what effect a single key has on the host. With a character mode host, a simple cursor movement can use three packets of 50 or more characters. Lack of knowledge about these internal communications can often lead to missed synchronization points.

In addition, this view allows an easy view of the data that comes from the host, allowing you to choose which data to use for synchronization. Review the information about nonprintable characters, such as control functions, that appear in the Datastream view.

If you select a procedure in the Model Debug Message list, the details in the lower right include a Copy button. You can copy the procedure results to the Clipboard.

Searching datastream content

When debugging a VT model, use the Suggest Escape Sequence button to have the model debug messages utility suggest a unique escape sequence (if present) that can be used to help synchronize the model. This option is available for VT models only.

You can copy text from this panel to the Clipboard by using the right-click menu or Ctrl+C keystroke. This is useful to paste into a WaitForCommString command (in the Operation Edit dialog box, or in the Host Event Edit dialog box after selecting Host Communication String event) to resolve synchronization issues.

Type a string into the text box at the bottom of the datastream window. All instances of that string in the datastream window are highlighted.

When debugging a VT model, the Next Packet option lets you move to the next packet using the same search string, simplifying the search process.

When debugging a VT model, the Previous Packet option lets you move to the previous packet using the same search string, simplifying the search process.

Use the Next Match button to move to the next occurrence of the string.

Use the Previous Match button to move to the previous occurrence of the string.

 

Related Topics
Bullet Debugging models
Bullet Using model debug messages