Chapter 7. Test Menu61202129L1-1 TSU 120 User Manual 7-7Press Shift+9 to clear results. The results are accumulated untilthe test pattern is set to N ONE or C LEARED.Using TST DS0s for testing can be very useful, particularly inFractional T1 applications. You can run an end-to-end test onthe Fractional DS0s by:1. Setting for Map B the TST in the same DS0 as used by MapA to receive data from an Nx/DBU port, and2. Looping the far end using a V.54 loopback code on the Nx/DBU port (DBU is TSU 120e only).In addition, a single DS0 can be used for continuous testingwhile other DS0s are passing normal data. This will also pro-vide an end-to-end check on the entire link. Set each end tosend QRSS in TST DS0s (using 1 DS0) and occasionally viewthe results on the PATTERN RESULT menu selection.Run Self-testThe self-test checks the integrity of the internal operation of theelectronic components by performing memory tests and bysending and verifying data test patterns through all internalinterfaces. Although actual user data cannot be passed duringthese tests, the self-test can be run with the network and DTEinterfaces in place and will not disturb any external interface.The memory portion of the self-test automatically executesupon power-up. A full self-test can be commanded from a frontpanel menu or from T-WATCH Pro.In addition to the specified self-tests, background tests are alsorun on various parts of the internal electronics. These run dur-ing normal operation to confirm continued correct functioning.This menu selection is used to execute a full internal self-test.The results of the self-tests are displayed in the LCD. Uponinvoking the command, the LCD displays S YSTEM S ELF- TESTand the test LEDs are illuminated. Test failures are displayed inthe LCD window.
