ADTRAN 1202076L2 - Manual (Page 40)

Chapter 2. Installation
2-14 TSU 600 User Manual 61202076L1-1
The Passcode, the Unit ID, and the Control Port settings are stored in a
nonvolatile memory. This ensures that they are operable for subsequent
power-up sequences.
Normal Power-Up Procedure
After the unit has been put into operation with the initial power-up and
initialization, subsequent power-up procedure includes only the Power-
Up Self-Test followed by the request for a passcode (password) if this
option was selected during initialization.
Use the number keys to key in the previously recorded passcode and
press Enter.