True or False: To display the contents of a device, you must generate a directory.

The correct answer is that it is true that to display the contents of a device, you must generate a directory. In the context of FANUC systems, generating a directory is essential because it creates an organized list or overview of all the files and data stored in a specific directory or device. This allows the user to see which programs, parameters, and other relevant data are present and accessible.

Generating a directory essentially reads the file system and presents the contents in a way that can be easily navigated. Without this directory, users would not have a clear view of what exists on the device, making it harder to manage files effectively or retrieve necessary data. This is particularly important for ensuring efficient workflow and data management.

The other options imply specific conditions under which a directory might be needed, but in general practice on FANUC systems, a directory is necessary regardless of the device type or operating mode.