Not able to set TX freq from c++ (branch trondeau/dbs)

GNU Radio
1

Hi,

I tried setting TX frequency using the c++ db branch. Setting the RX
frequency
works fine, setting the TX frequency using the python code works as
well.

The problem, as far as I could pin it down, is the missing lock. Result
from
io_read is: 0xff5b.

Regards,

Stefan

–
Stefan Brüns / Bergstraße 21 / 52062 Aachen
mailto:lurch at gmx.li http://www.kawo1.rwth-aachen.de/~lurchi/
phone: +49 241 53809034 mobile: +49 151 50412019

2

Found the bug, at least the first:
db_flexrf.cc:

flexrf_base_tx::flexrf_base_tx(usrp_basic usrp, int which, int
_power_on)
: flexrf_base(usrp, which, _power_on)
{
/
@param usrp: instance of usrp.sink_c
@param which: 0 or 1 corresponding to side TX_A or TX_B
respectively.
*/

d_usrp = (usrp_basic_tx*)usrp;
d_tx = true;

int d_spi_enable; // <-- shadows class member!
if(which == 0) {
d_spi_enable = SPI_ENABLE_TX_A;
}
else {
d_spi_enable = SPI_ENABLE_TX_B;
}

At least, the board is able to tune to the right frequency, and I was
able to
send a few times.

Unfortunately, after running a few other (python) examples, it stopped
working, so I think, the python code modifies some registers and the c++
code
is not able to set this registers to working values.

Disconnecting power from the USRPs did not help - any hints?

Stefan

3

Stefan Bruens wrote:

Stefan,

Thanks, that was indeed a bug. It has been fixed in my branch as of
r9682.

This is also the first time that I’ve had the equipment in my new place
to test the transmitters, so, frankly, I’m impressed that this is the
only bug so far.

Tom

4

On Tuesday 16 September 2008 05:05:37 Tom R. wrote:

Stefan,

Thanks, that was indeed a bug. It has been fixed in my branch as of r9682.

This is also the first time that I’ve had the equipment in my new place
to test the transmitters, so, frankly, I’m impressed that this is the
only bug so far.

Found some more, added a tx test application, and streamlined the flexrf
code
somewhat.

See followup for patches.

Tom

–
Stefan Brüns / Bergstraße 21 / 52062 Aachen
mailto:lurch at gmx.li http://www.kawo1.rwth-aachen.de/~lurchi/
phone: +49 241 53809034 mobile: +49 151 50412019

5

On Tuesday 16 September 2008 14:24:49 Stefan Brüns wrote:

output of svn diff dbs/config dbs/gnuradio-examples/c++/usrp_test_tx

Stefan