Re: [Discuss-gnuradio] Mux settings...

[Eric Blossom]

On Tue, Oct 23, 2007 at 08:42:59AM -0700, Hans Glitsch wrote:
> >
> >For the Basic Rx, 0xf3f2f1f0 is the correct setting to feed 4 separate
> >signals into the I inputs of 4 DDCs, with zeros fed to the Q inputs.
> >
> >To use 4 channels, you must use the std_4rx_0tx.rbf fpga image.
> >If you use the std_4rx_0tx.rbf image, the decimation rate must be <= 128.
> >If you need more decimation, you must do it in software.
> >
> >Eric
> >
> 
> I wasn't aware that I couldn't use a decimation of 250.  250 seemed to work 
> fine with release 3.0.

This is the problem that was reported last week.  Without the halfband
in the FPGA, the CIC sections aren't wide enough to support decimation
> 128 without losing information.

> Are odd numbers ok? Can I use a decimation of 125?

With the std_4rx_0tx.rbf image, I believe odd numbers will work.
They will not work with std_2rxhb_2tx.rbf

> Thanks,
> Hans 

Eric