Motherboard Re-Clocking Questions
FIXME this section is outdated, from before c++ drivers.
� I would like to run my USRP off a 44 MHz clock
instead of the 64 MHz clock that is currently
used. Can I generate a 44 MHz clock from the 64
MHz or do I have to change the crystal? If I
change over to the 44 MHz will everything else
still work? Especially the DBSRX and RFX2400
boards?
You need a new crystal or an external oscillator. You'll need to
change the definition of
/*!
**** rief return frequency of master oscillator on USRP
*/
long fpga_master_clock_freq () const { return 64000000; }
in source:usrp/host/include/usrp/usrp_basic.h Proced
ure: I purchased a 44 MHz oscillator from digi-key (p/n 300-
7254-1-ND, CSX750FJC44) for $3.38. The first attempt to
remove the USRP 64 MHz failed miserably with a pen iron. I
purchased a heat gun from digi-key (MA1008-ND) for $52,
set it to the 1000 degree setting and the old oscillator came
up in about 10 seconds. Installed the new oscillator and
