Cant open usrp

My USRP has something wrong when started. when i want to open USRP, I
input
the command: usrp_fft.py -R B. but the system mentioned that:
RuntimeError: cant open usrp, failed to load fpga bitstream
/usr/share/usrp/rev4/std_2rxhb_2tx.rbf.
what 's wrong with my USRP? how can I fixed it?

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On Mon, Oct 25, 2010 at 11:15 AM, zhdiamond [email protected]
wrote:

My USRP has something wrong when started. when i want to open USRP, I input
the command: usrp_fft.py -R B. but the system mentioned that:
RuntimeError: cant open usrp, failed to load fpga bitstream
/usr/share/usrp/rev4/std_2rxhb_2tx.rbf.
what 's wrong with my USRP? how can I fixed it?

During the fpga load, one of the LEDs will turn on and stay on for the
duration the loading process, which is about one second. If the LED
never turns on, there is a problem occurring prior to the loading of
the fpga. Otherwise, it is likely that the fpga load itself is
failing.

Thomas