Each of the CD-ROM test cases can be executed by invoking the DDTT from either a command line, a batch file, or a REXX file. Test scripts are described below. The user is free to create additional tests or construct multi-threaded test cases after becoming familiar with the DDTT and the CD-ROM grammar files.

Test scripts generally start by opening to the device (CDROM_OPEN) and closing at completion (CDROM_CLOSE). The device open will not succeed unless a disc is present. All test scripts log information to a log file of the same file name, but with a file name extension of .LOG. When current status is queried (for example, track, channel, or drive), this data is written to the DDTT's scroll output window and to the log file. Log files can be examined with a text editor after the test case has completed.

The CD-ROM Play-Audio function causes the CD-ROM drive to play the audio media by sending the audio signal to the CD-ROM's own pre-amplified outputs. The audio is not played through the system speaker or any multi-media device.

CD-ROM discs are accessed by Logical Block or Redbook format. Logical block format sequentially addresses each block on the disc starting at 0. Redbook format addresses each block using a time format of MM:SS:FF (MM represents minutes from the start of the CD, SS represents seconds, and FF represents frames.) Each frame represents 1/75th of a second. Logical block 0 and Redbook format block 0:2:0 are coincident and both represent the first addressable block.