How does uhd (for usrp2) talk to a signal?

Hello,
I am new to UHD. I have 2 questions about uhd. Maybe for your sides they
are very simple, but …

  1. I don’t know about how can i send a siganl to uhd. Could you give me
    a simple example? For example, source is a sinewave signal, combined
    with USRP2 (all parameters are default values).

  2. Except for GNU, can I make uhd to talk with the generated code from a
    simulink model? I know that Simulink has the ursp block (SDRu), but I
    want to run the model in real time linux, so i generate code from model
    and compile the code in Linux. Mathwork don’t support the source code
    for usrp block, i cannot finish the compiling, because its library(usrp
    block) libmwusrp_uhd_capi.dll cannot be linked in Linux. I don’t know
    whether i can make uhd to talk with code (Simulink model with usrp
    block).

I need your help and suggestion.
many many thanks!!!

Yanlei