I am trying to make loopback call on osmo-bts VTY interface using ettus B200/B210 hw.

 in vty.c file i can see options available for loopback call , but loopback call is not started once triggered from  osmobts VTY interface. 

Can some one help ?

DEFUN(bts_t_t_l_loopback,

                bts_t_t_l_loopback_cmd,

                "bts <0-0> trx <0-0> ts <0-7> lchan <0-1> loopback",

                BTS_T_T_L_STR "Set loopback\n")

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