<p dir="ltr">Am 23.10.2013 19:14 schrieb "Andreas Kemnade" <<a href="mailto:andreas@kemnade.info">andreas@kemnade.info</a>>:<br>
><br>
> On Wed, 2013-10-23 at 18:52 +0200, Andreas Kemnade wrote:<br>
> > On Wed, 2013-10-23 at 15:25 +0200, Christoph Mair wrote:<br>
> > > On Wed, Oct 23, 2013 at 1:06 PM, Andreas Kemnade <<a href="mailto:andreas@kemnade.info">andreas@kemnade.info</a>> wrote:<br>
> > > > On Mon, 2013-06-24 at 11:38 +0200, Dr. H. Nikolaus Schaller wrote:<br>
> > > >> Hi,<br>
> > > >> fm-radio appears to work. At least on one board (the one where I did solder some wires to measure the clocks and PCM signals).<br>
> > > >> [...]<br>
> > > >> Now comes the bad news: it works only on one GTA04 board and I don't<br>
> > > >> know why it fails on the others I have tested. Since they have no wires I<br>
> > > >> can't check if the clocks are available and the Si47xx is sending PCM<br>
> > > >> to the CPU or not. Or if there is something unreliable in the McBSP config.<br>
> > > >><br>
> > > >> It could also be some hardware issue. If you look into the schematics, there<br>
> > > >> are series resistors for the McBSP1 interface. Their values are choosen<br>
> > > >> based on the recommendations of a reference design we had found.<br>
> > > >><br>
> > > >> But 2k2 appears a little high value, taking into account that we have a 2.5 MHz<br>
> > > >> clock. I.e. the signals may be damped and too slow so that e.g. the clocks<br>
> > > >> are not recognized correctly.<br>
> > > >><br>
> > > > I do not understand the connection here. The McBSP sends out its clocks.<br>
> > > > It should look at the data pin at the right times and interpret whatever<br>
> > > > is avilable there at sampling time if i understand the I2S stuff<br>
> > > > correctly. So we should be able to read some suff and arecord should<br>
> > > > spit out something.<br>
> > ><br>
> > > One thing which comes to my mind: did you mux the clock output pin as<br>
> > > input? While this seems wrong, the McBSP needs this configuration to<br>
> > > use its own clock as receive clock. The pin works as output<br>
> > > nonetheless.<br>
> > ><br>
> > Ehm,.. I should have followed the link about uboot in the mail. As<br>
> > pinmux settings in uboot are of course right (everything to output I<br>
> > thought, I have checked that often), I thought hns has accidently run an<br>
> > ancient uboot instead of an old one...<br>
> > So I did not update my uboot. Ok, that seems to be the missing part of<br>
> > information I needed all the time when I was experimenting with that.<br>
> > At least I now get something out of the McBSP1. Now I am searching my<br>
> > headphone.<br>
><br>
> Ok, I found my headphone, I put the gta04 near a window on the side<br>
> towards the radio station, replaced the arecord | aplay pipe in the<br>
> script by<br>
><br>
> arecord -D default:CARD=gta04fm -r 48000 -f S16_LE -c 1 | aplay -r 48000<br>
> -f S16_LE -c 1<br>
><br>
> and I had reception with good sound quality.</p>
<p dir="ltr">Hey, congrats! Great to hear that :)</p>
<p dir="ltr">Regards,<br>
Christoph<br>
</p>