Toggling LFRX gpio pins

GNU Radio
1

Hi guys again,

I have designed small RF frontend using TI’s cc1000 transciever. Since
the
transciever need to be configured using external pins, I need to be able
to
toggle gpio pins on my LFRX. I have found that I should use dboard_iface
which is available in python via swig. However I have several questions:
How should I address my board, since there are 4 possible slots, and
onlt 2
values of type unit, UNIT_RX and UNIT_TX.
As far as i can see, every uhd source has method get_iface, does this
anyhow concerns me?

Thanks again,
Nemanja

2

After some time I maybe realized how this thing works, but I don’t know
jow
to call correctly methods from dboard_iface:

def get_pin_ctrl(self, *args, **kwargs):
“”“get_pin_ctrl(self, unit_t unit) -> boost::uint16_t”""
return _uhd_swig.dboard_iface_get_pin_ctrl(self, *args,
**kwargs)

ef get_gpio_ddr(self, *args, **kwargs):
“”“get_gpio_ddr(self, unit_t unit) -> boost::uint16_t”""
return _uhd_swig.dboard_iface_get_gpio_ddr(self, *args,
**kwargs)

or any of these methods that have *arg and **kwargs. When I call like
this:
iface = usrp1_src.get_dboard_iface()
print iface.get_pin_ctrl(uhd.dboard_iface.UNIT_RX, 0)

I get following error:

Traceback (most recent call last):
File “lftx_io.py”, line 31, in
print iface.get_pin_ctrl(uhd.dboard_iface.UNIT_RX, 0)
File
“/usr/local/lib64/python2.6/site-packages/gnuradio/uhd/uhd_swig.py”,
line 1691, in get_pin_ctrl
return _uhd_swig.dboard_iface_sptr_get_pin_ctrl(self, *args,
**kwargs)
TypeError: dboard_iface_sptr_get_pin_ctrl() takes at most 2 arguments (3
given)

3

On 07/24/2013 12:46 PM, Nemanja S. wrote:

line 1691, in get_pin_ctrl
return _uhd_swig.dboard_iface_sptr_get_pin_ctrl(self, *args, **kwargs)
TypeError: dboard_iface_sptr_get_pin_ctrl() takes at most 2 arguments (3
given)

You have the right idea, but that particular function only takes one
argument. So thats the error.

Take a look at include/uhd/usrp/dboard_iface.hpp for documentation. The
python interface may be a little different syntax wise, but the function
names are all the same.

-josh

4

Hi,

thank you Josh. Yesterday late I figured out almost everything. I
suppose
everything would be faster with a little bit more documentation.
So, I have USRP1 with wbx, lftx and lfrx.
There is one doubt now. When I set USRP source to wbx and after that
read
register for setting direction of the pins i get some value (49116). The
binary representation is not the same as i expect from WBX schematic. In
schematgic is written that for example io_rx[5] for selecting rx1 or rx2
is
output pin, but I get 0 when I read. Also io_rx[15] and io_rx[14] are
unused, but still one is set as output and other as input. Also when I
change antenna selection and read the same value again i read the same
number.

thanks,
Nemanja