ashtech DG16 Reference Manual page 345

If you have purchased the User Defined Messaging option [X], then you can use
the UDM Utility program to create the script file which defines the custom
messages. You can use the custom message feature to set the receiver to output
only the information you need in a single message. This can save you from
sending several receiver commands.
UDM Utility is designed for 32-bit operating systems: Windows 95, 98, 2000, or
NT4.0, with a 486/66 computer or better.
To install the UDM Utility program, perform the following steps:
1. Insert the UDM Utility installation disk.
2. Click on the Windows Start menu and select "Run".
3. Type in "a:\setup.exe", where the "a:" is the letter of your CD-ROM drive.
4. Follow the instructions of the installation program.
UDM Utility is intended to create the format of a receiver command. Receiver
commands are used to output various operating/solution parameters such as
elevation mask, latitude of antenna, and operating mode. UDM Utility allows the
user to create commands to output solution or receiver parameters. The user can
construct a project with output commands, then compile this project and upload to
the GPS receiver.
UDM Utility 325