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Diffstat (limited to 'host/docs/usrp_nxxx.rst')
| -rw-r--r-- | host/docs/usrp_nxxx.rst | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/host/docs/usrp_nxxx.rst b/host/docs/usrp_nxxx.rst index 1c270df08..575f0ff70 100644 --- a/host/docs/usrp_nxxx.rst +++ b/host/docs/usrp_nxxx.rst @@ -227,19 +227,27 @@ The LEDs reveal the following about the state of the device: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Ref Clock - 10MHz ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -Using an external 10MHz reference clock requires a signal level between -+5dBm and +20dBm at 10MHz applied to the Ref Clock SMA port on the front panel. +Using an external 10MHz reference clock, square wave will offer the best phase +noise performance, but sinusoid is acceptable. The reference clock requires the following power level: + +* **USRP2** 5 to 15dBm +* **N2XX** 0 to 15dBm ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PPS - Pulse Per Second ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -Using a PPS signal for timestamp synchronization requires a 5Vpp square wave signal +Using a PPS signal for timestamp synchronization requires a square wave signal with the following amplitude: + +* **USRP2** 5Vpp +* **N2XX** 3.3 to 5Vpp + +Test the PPS input with the following app: + +* <args> are device address arguments (optional if only one USRP is on your machine) -Test the PPS input of the USRP2 with the following app: :: cd <prefix>/share/uhd/examples ./test_pps_input --args=<args> -* <args> are device address arguments (optional if only one USRP is on your machine) |