To process the sample messages that you saw in Analyzing Your Incoming Message, you must create a VMD file in which the following HL7 segments are defined:

• The MSH segment, since every message processed by Chameleon is assumed to start with this segment;
• A custom segment that contains the data provided in the sample messages. The name of this segment must start with Z, since all custom segments start with this letter. This example uses ZSU as the name of the custom segment.

To create the VMD file and define the segments:

• Start Chameleon, and click New to create a new VMD file.
• From the Workspace menu, select Import Segments From Library.
• In the Import Segments From Library window, ensure that the Import segments from a library radio button is selected. Also ensure that HL7 2.6 has been selected from the list box next to this radio button.
• Click Next.
• From the list of check boxes, select MSH. Click Next.
• Click Finish to close the window. The MSH segment and its composites are now displayed in the Workspace panel at the left:

Now that you have imported the MSH segment, the next step is to define the custom ZSU segment:

• In the toolbar, click Segment. A segment named Segment1 appears in the Workspace.
• Right-click Segment1 and select Rename. Name this segment ZSU.
• Double-click ZSU to display the Segment window. In this window, define the data fields that are shown in the picture below. These fields are the fields that appear in the sample message, listed in the order in which they appear in the message. (The first field, DateTimeOfMessage, matches the date enclosed in square brackets [ ] at the left of each message.) Note that all fields have a Data Type of ST (string).

• In the Description field, type Arbitrary Segment.

You have now defined all the segments that your message will need. The next step is to write the Global Inbound Script that converts your incoming message into the HL7 message format.