User manual

905U-D Radio Modem User Manual
Man_905D_1.10.doc Page 52
Chapter Six TROUBLESHOOTING
6.1 Diagnostics Chart
INDICATOR
CONDITION
MEANING
OK LED OFF
Continuously
• Power supply failure
• CPU failure
OK LED ON
Continuously
• Normal Operation
Radio TX LED ON
Flashes briefly
• Radio transmitting
Radio RX LED ON
GREEN flash
RED flash
• Radio receiving data
• Weak radio signal (< -95dBm)
Serial RX LED ON
GREEN flash
RED flash
• Serial Port Receiving
• Input buffer almost full
Serial TX LED ON
Flashes briefly
• Serial port transmitting
DCD LED ON
Continuously
• In transparent mode, always on.
• In controlled mode, a radio link
has been established.
The green OK LED on the front panel indicates correct operation of the unit. This LED extinguishes
on failure as described above. When the OK LED extinguishes shutdown state is indicated. On
processor failure, or on failure during startup diagnostics, the unit shuts down, and remains in
shutdown until the fault is rectified.
6.2 Test Functions
6.2.1 Radio Testing - AT&Tx
To aid in the checking and setup of the 905U-D unit, diagnostic functions are provided using the
standard Hayes AT commands. To perform the tests, you will need a terminal (PC + hyper-
terminal) set-up to match the module (same character type and serial speed). The table below
outlines the functions of the various tests:
AT&T
Self Tests. Allows in-field diagnostics, and factory testing.
&T0
Transmit Bit Error Rate Test. Generates pseudo random data and sends out radio.
&T1
Receive Bit Error Rate Test. Receives data from &T0 module, and displays BER
statistics.