61200.078L1-1
DSU 5600 User Manual
13
Chapter 3. Test Modes
Chapter 3
Test Modes
In addition to a self test mode, other DSU 5600 test modes allow
the user to isolate problems to specific components of the
communications circuit. These various test modes for the DSU
5600 are initiated and terminated from the front panel using
Select
and
Test
.
SELF TEST
When the DSU 5600 is powered on, all LEDs on the front panel
turn
On
simultaneously for approximately two seconds then
turn
Off
briefly. The LEDs then cycle
On
in pairs with a fan-out
pattern away from the
ALM
indicator. Next, the LEDs cycle
Off
in pairs with a fan-in pattern back towards the
ALM
indicator.
These patterns are repeated four times to determine that all
LEDs are functioning properly.
At completion of the LED test patterns the
PTRN
LED is
On
,
indicating the DTE with TP test is being performed. This test is
successful if the
Error
indicator does not turn
On
. If the DTE
with TP test fails, the
RS
,
ALM
,
DTE
,
PTRN
, and
Error
indica-
tors all
Flash
.
If an EPROM CHECKSUM failure is detected during self test,
CS
,
ALM
,
PTRN
, and
Error
indicators
Flash
at the end of the self
test.