ad9361 digital loop back

Hello all,

I am using the ad9361 SOM board and I can transmit my own signal (dac_init(ad9361_phy, DATA_SEL_DMA, 1); ) and receive it correctly. The TX1A antenna is connected with a cable to the RX1A connector. I remember reading somewhere that I can loop back the digital data instead of going through the RF !?...is that possible?...and how please?

Vivado 2017.1 and no-os

Regards,

Murad