[Discuss-gnuradio] USRP decimation range change while upgrading from gnuradio 3.1.2 to 3.2.2

[Todd Borrowman]

I have been using the USRP and gnuradio version 3.1.2 to run the back-end of a 
4 channel UHF radio for about a year.  I use the std_4rx_0tx.rbf firmware and 
decimate by 250 to give me a 256 kHz bandwidth.  I recently upgraded to 
gnuradio version 3.2.2 to begin a similar project.  In this version I can only 
decimate up to 128 in the fpga.

Does this mean that the halfband filter is no longer implemented in the 
firmware, or that it was never implemented and the decimation done previously 
was erroneous (could contain aliased signals)?

Additionally some of the function calls for the usrp, such as nddc() and 
nduc(), have been changed, to nddcs() and nducs().  Is there a compatibility 
issue from the old usage to the new or was this a stylistic change?

Thank you,
Todd Borrowman