Re: [Discuss-gnuradio] about tune the daughterboard

[Eric Blossom]

On Fri, Jul 21, 2006 at 01:31:57PM -0700, WaveMaker wrote:
> 
> What "code of GMSK2" are you talking about?
> 
> I read this in CVS at
> http://cvs.savannah.gnu.org/viewcvs/gnuradio/gnuradio-examples/python/gmsk2/benchmark_gmsk_tx.py?rev=1.19&view=markup
> and it does not contain any mention of tune.
> 
> This code is only 3 weeks old, so I'm ASSsuming it's good :)

FYI, I think he's talking about the receive_path and transmit_path code.

> 
> 2 1 wrote:
> > 
> > Hi, all:)
> > I've read through the code of GMSK2 and I found the difference of tune in
> > transmit_path and receive_path.
> > In the transmit_path:
> >     self.u.tune(self.subdev._which, self.subdev, target_freq)
> > In the receive_path:
> >     self.u.tune(0, self.subdev, target_freq)
> > 
> > The self.subdev._which indicate the channel of TX/RX, 0 for A, 1 for B.
> > (Am
> > I right?)

No, you're not right.  They transmit and receive set ups are different
because of the location of the muxes and DDC/DUC are in different
places in the two cases.  The code above is correct for the single
channel case, regardless of which slot or daughterboard you are using.

> > So I am confused about why the first parameter of tune depends on channel
> > selection in transmit_path while it's set to 0 in receive_path?

Don't worry, be happy.  As long as you are using a single channel,
the code above works perfectly.

The detailed answer requires a diagram of the full transmit and
receive paths.  Somebody was working on this  a while ago, and I'm
pretty sure what they came up with was right, or pretty close.
Don't recall where it's stashed.

[There's work taking place in the background to get the wiki turned
back on.  Should be in place by sometime next week.]

Sorry for the delay in getting back to you on this.  I'm currently
vacationing, and have intermittent connectivity.

Eric