Re: [Discuss-gnuradio] help: cannot send after transport endpoint shutdown

[Eric Blossom]

On Sat, Jan 31, 2009 at 10:59:10PM +0800, Joreen Tan wrote:
> 
> Hi,
>
> i am actually trying to do a half duplex (receive) using one board
> (900MHz) and half duplex (transmit) using another board (1800MHz) in
> the same usrp. I have another usrp for the same function.

> I actually make use of the benchmark_rx and benchmark_tx files to
> modify the codes to make the receiver send an acknowledgement back
> to the transmitter to acknowledge the receive of the packet and
> proceed with asking the transmitter to send the next packet.

> I used the following code inside the transmitter, to call the
> receiver to wait for an ack.
>
> os.system("python benchmark_tx.py --freq 900 --bitrate 500k")
>
> The program is able to activate and start to receive. However, i
> couldn't actually stop the receiver to go back to the transmitter
> mode after doing so.

Joreen, I think this will be easier if you keep both the transmitter
and receiver in a single top_block, like is done with tunnel.py.
benchmark_rx uses receive_path as does tunnel.py.  Likewise
benchmark_tx uses transmit_path as dooes tunnel.py
My thought is that you ought to be able to reuse the guts of
benchmark_tx and rx in a single program that does what you want.

Also, I don't think that you need to explicitly stop the receiver.
The Auto T/R stuff will ensure that it's stopped when the transmitter
is running.

Eric