Eric,

Thank you for your prompt comment.  :-)

My mistake on the previous explanation. Actually, what I want to do is not
simply change the filter coefficients but to change the entire filter.

To prevent the sample value converge to '0' by the hardware decimation
filters in FPGA(I posted once asking this matter before), I fixed the usrp2
decimation rate to '4' and implemented software decimation filters.
The filter frequency band(passband cut-off, stopband cut-off) and number of
decimation would dynamically changes. So, my idea is to re-generate the
filter every time the user command changes. To do this, I thought I had to
perform the 'lock/disconnect/changing_filter(s)/connect/unlock' procedure.
(The filter(s) shall be between 'self.u' and 'self.s2v' in my previous post)

1. Am I on the right track? Or, still can I just change the filter coeffs.
and decimation rate at runtime?

2. Filter coeffs. and decimation rate are two parameters of
gr.fir_filter_ccf() function to generate a decimation filter. What function
can I use to change the parameters of running filter instance?

3. This is an off topic, but I wonder if gnuraio.org server is still down. I
could not have connected the site since evening of the day before yesterday.

Regards,
ILKYOUNG.

2010/1/3 Eric Blossom <e...@comsec.com>

> On Sun, Jan 03, 2010 at 02:41:35AM +0900, ILKYOUNG KWOUN wrote:
> > Happy New Year! folks,
> >
> > I need to dynamically change software filter coefficient according to
> user
> > command while the program is running.
> > So, I made a test program similar to the following.
>
> There's no reason to do all this lock/disconnect/connect/unlock stuff
> if all you want to do is change the filter coefficients.
>
> Just set them.
>
> Eric
>
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