0049-2702-XXX Alliance Series Modems – USER MANUAL
08/05/2010
Rev. A
Page 146 of 197
Front Panel Control
From screen 2 of the LCD MAIN MENU, select TEST. This will take you to screen 1 of the
LOCAL TEST menu, where ALBST will be visible as one of the selections. Select ALBST.
The SELFTEST screen will be displayed, with ON and OFF as the possible selections. Select
ON to activate the test. The TIA/EIA status screen will be displayed while the test is being
conducted. If “ER” is present on the LCD, data errors have occurred. The ER indicator may
flash on when the test is first turned on, but it should quickly go out and remain off until the end
of the test.
To end the test, press the ENT pushbutton to return to the SELFTEST screen, and then select
OFF.
Analog Loopback Self Test with Errors (ST/E)
This test can only be initiated through the front panel LCD; there is no AT command for it.
In the analog loopback self test with errors, data is sent and received by an internal 511-bit
pattern generator and receiver; therefore, no DTE or external BERT is necessary. This test
differs from the ALBST in that errors are injected into the data flow every few seconds. The
data flow is the same as that shown in Figure 6-2 (the ALBST).
To run this test, follow these steps:
From screen 2 of the LCD MAIN MENU, select TEST. This will take you to screen 1 of the
LOCAL TEST menu, where ST/E will be visible as one of the selections. Select ST/E.
The SELFTEST W/ERROR screen will be displayed, with ON and OFF as the possible
selections. Select ON to activate the test. The TIA/EIA status screen will be displayed. The ER
indicator should flash every few seconds, indicating that the pattern generator and detector are
working. Errors are injected every few seconds. To end the test, press the ENT pushbutton to
return to the SELFTEST W/ERROR screen, and then select OFF.
External Analog Loopback (ALBX) Test
The external analog loopback test is available for
4-wire leased line mode only
.
The ALBX test checks the local modem and its associated terminal and verifies the availability
of the leased line circuit. The test circuit does not include the remote modem. Figure 6-3 shows
the connections automatically made during the ALBX test.