National Instruments USRP-2940, Getting Started Manual

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Table 4. USRP-2940 Module LEDs
LED Description Color State Indication
RF 0 TX1
RX1
Indicates the transmit
status of the module. OFF — The module is not active.
Red Solid The module is transmitting
data.
Green Solid The module is receiving
data.
RX2 Indicates the receive
status of the module. OFF — The module is not
receiving.
Green Solid The module is receiving.
REF Indicates the status of
the reference signal. OFF — There is no reference
signal, or the device is not
locked to the reference
signal.
Green Blinking The device is not locked to
the reference signal.
Solid The device is locked to the
reference signal.
PPS Indicates the pulse per
second (PPS). OFF — There is no PPS timing
reference signal, or the
device is not locked to the
reference signal.
Green Blinking The device is locked to the
PPS timing reference
signal.
GPS Indicates whether the
GPSDO is locked. OFF — There is no GPSDO or the
GPSDO is not locked.
Green Solid The GPSDO is locked.
LINK Indicates the status of
the link to a host
computer. OFF — There is no link to a host
computer.
Green,
yellow, or
red Solid The host is actively
communicating with the
device.
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