random range value when testing gr-radar on just one X310 about gr-radar HOT 1 OPEN

Hi,I'm testing gr-radar on just one X310 with two daughterboards. Firstly, I tried to transmitting and receiving the signal in the same channel(A:0 TX/RX and RX2), but the range value was always a constant even I changed the distance of two antennas, I thought the reason was that the signal leaked from the transmitting port to the receiving port. Then I modified the file of usrp_echotimer_cc_impl.cc to add a choice of selecting the subdevices(A:0,B:0), and it works when transmitting with A:0 TX/RX and receiving with B:0 RX2, but the problem was that the initial range value changed randomly each time. Whenever the program restarted, the initial range value was a random value, and when the distance of two antennas changed, the range value changed based on the initial value, it seems that it takes a random time to complete the configuration process of transmitting and receiving, so I can't to determine the initial value. I have tried a bit to fix this problem with the time command, but it doesn't work well. so, how to fix it? Would anyone be so kind as to let me know, How to solve this problem?

Hello! I've encountered the same question when implementing gr-radar onto x310, would you please share how you modify the file of usrp_echotimer_cc_impl.cc to make it work? Thank you very much!

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