[Discuss-gnuradio] USRP / LFTX controlling I/O pins

[Faschingbauer, Alexander]

Hello,

the following code snippet is part of a runnable python script.
I want to control some or one of the I/O pins on the USRP / LFTX board but I 
can't measure any changes on the USRP / LFTX io_pins by using the following 
code snippet.

Could somebody give me a hint please what to do ?
I'm not sure especially about the "#not sure" commented lines...

...
u = usrp.sink_c(0,usrp_interp)
tx_subdev_spec = usrp.pick_tx_subdevice(u)
m = usrp.determine_tx_mux_value(u, tx_subdev_spec)
print "mux = %#04x" % (m,)
u.set_mux(m)
subdev = usrp.selected_subdev(u, tx_subdev_spec)
print "Using TX d'board %s" % (subdev.side_and_name(),)
u.set_tx_freq (1, cordic_freq)
u.set_pga(0,0)
print "Actual frequency: ",u.tx_freq(1)
subdev.set_enable(True)
subdev.set_auto_tr(True) # enable auto T/R

u.write_atr_mask(1, 21) #not sure
u.write_atr_txval(1,  21) #not sure
u.write_atr_rxval(1, 21) #not sure
...

Thank' s in advance,

Alex (DM5AX)