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9. Troubleshooting
RAP-B511 series
– User's Manual
67
Troubleshooting
Usually, if the system seems not to transport the signal as expected, the best
strategy for troubleshooting is to check signal integrity through the whole
signal chain starting from source side and moving forward to device end.
At first, check front panel LEDs and take the necessary steps according to their states. For more information
about status, LEDs refer to
and
sections.
Symptom
Root cause
Action
RS-232 signal
Connected serial
device does not
respond
Cable connection
problem
Check the connectors to fit well; check the wiring of the
plugs.
RS-232 settings are
different
Check the port settings of the RAP-B511 and the
connected serial device(s).
RS-232 mode is not right
Check the RS-232 mode settings (control, command
injection, or disconnected)
Network
No LAN
connection can be
established
Incorrect IP address is
set (fix IP)
Use dynamic IP address by enabling DHCP option.
Restore the factory default settings (with fix IP).
IP address conflict
Check the IP address of the other devices, too.
GPIO
Connected device
does not respond
Cable connection
problem
Check the connectors to fit well; check the wiring of the
plugs.
Output level
cannot be changed
The direction of the
selected pin is set to
input
Check and modify the direction setting of the desired pin
Miscellaneous
Front panel
buttons are out of
operation
Buttons are set as
locked in LDC
Unlock the buttons