Re: [Discuss-gnuradio] TDMA Engine Error

[Sam mite]

On Mon, Apr 29, 2013 at 12:53 PM, Sam mite <address@hidden> wrote:

On Fri, Apr 26, 2013 at 10:15 AM, Josh Blum <address@hidden> wrote:

>   File "/home/s/tdm/tdma_radio.py", line 70, in __init__
>     freq=freq,
>   File "/home/s/.grc_gnuradio/tdma_hier.py", line 76, in __init__
>     self.tdma_engine =
> precog.tdma_engine(initial_slot,slot_interval,guard_interval,number_of_slots,lead_limit,link_speed)
>   File "/usr/local/lib/python2.7/dist-packages/precog/tdma_engine.py", line
> 100, in __init__
>     self.set_tag_propagation_policy(extras_swig.TPP_DONT)
> NameError: global name 'extras_swig' is not defined
>

Looks like an import got removed from that file, but I dont think its
needed.

try changing this trouble line to

self.set_tag_propagation_policy(gnuradio.extras.TPP_DONT)

Or if that doesnt work

from gnuradio import extras
self.set_tag_propagation_policy(extras.TPP_DONT)

-josh

Thanks that solved the problem. tdma_radio.grc ran without any error with output as follows:

UHD Warning:
    The send buffer could not be resized sufficiently.
    Target sock buff size: 1048576 bytes.
    Actual sock buff size: 1000000 bytes.
    See the transport application notes on buffer resizing.
    Please run: sudo sysctl -w net.core.wmem_max=1048576

--     1) catch time transition at pps edge
--     2) set times next pps (synchronously)
--     1) catch time transition at pps edge
--     2) set times next pps (synchronously)

>>> gr_fir_fff: using SSE

How can I use tdma_engine in my following FSK flow graph;

TX Flow graph:

File source ---> Packet Encoder ---> pack to unpack/chunks to symbol --> upsample  by 8---> Freq Mod---> USRP

Lets say USRP sampling rate is 500k.

 I want USRP to transmit for 1 second and then wait for 2 second (in these two seconds two other same type of transmitters would transmit)and this process should continue.  Can I do that? Where should I place this "tdma_engine" block. And what would be the values for its parameters?

Thanks for the time.

--

Best Regards,

Sam

Any thoughts or comments on this, please. Anyone done this before?

--

Best Regards,

Sam