It's a bit obscure, but the default is set in the register map: https://github.com/EttusResearch/uhd/blob/master/host/lib/ic_reg_maps/gen_zbx_cpld_regs.py#L111
(i.e., default is cal-loopback). --M On Tue, Sep 23, 2025 at 11:15 PM Rob Kossler via USRP-users < [email protected]> wrote: > Thanks for the reply Martin, > I looked at the linked code, but it looks to me like it doesn't provide > the answer. It seems to me that my question boils down to figuring out the > four entries in the lookup table RX0_ANT_1 which holds a switch setting for > each of the ATR states: 0X, RX, TX, XX. > > After reviewing the code snips you linked as well as where these functions > are called from the zbx rx/tx programming experts for the specific case of > the Rx antenna configured for Tx/Rx and the Tx antenna configured for > Tx/Rx, my mental compiler tells me that the only entry in RX0_ANT_1 that > will be modified during the configuration is the ATR state RX. The other 3 > states (0X,TX,and XX) in the table are not touched. I'm guessing that these > are defaulted elsewhere in the code, but I can't figure out where. > > Rob > > On Tue, Sep 23, 2025 at 10:09 AM Anderseck, Martin via USRP-users < > [email protected]> wrote: > >> Hi Rob, >> >> >> >> Looking into the zbx_cpld_ctrl.cpp it looks like the RX Ant1 switch is >> not moved away from the TX/RX port: >> >> >> https://github.com/EttusResearch/uhd/blob/master/host/lib/usrp/dboard/zbx/zbx_cpld_ctrl.cpp#L322-L325 >> >> and >> https://github.com/EttusResearch/uhd/blob/master/host/lib/usrp/dboard/zbx/zbx_cpld_ctrl.cpp#L276-L277 >> >> >> >> For the TX part I’d have to look up what the amplifiers in the antenna >> settings mean exactly, though. >> >> >> >> /Martin >> >> >> >> *From:* Rob Kossler via USRP-users <[email protected]> >> *Sent:* Monday, September 15, 2025 10:23 PM >> *To:* usrp-users <[email protected]> >> *Subject:* [EXTERNAL] [USRP-users] Rx antenna Tx/Rx with full duplex >> streaming state >> >> >> >> Hi, >> >> I am wondering if anyone knows what happens with the Tx and Rx switches >> in the case of the Rx antenna setting of Tx/Rx for a full-duplex streaming >> state. In particular, I'm interested in the case of the X410/ZBX where the >> switches in question are Sw 1 (Rx) and Sw 11 (Tx). It seems that if the >> streaming state were Rx only, both of these switches would route the Tx/Rx0 >> port to the Rx path. But, for the case of simultaneous Tx/Rx streaming, I >> expect that Sw 11 (Tx) is changed to the Tx path. What I'm unclear about is >> what happens to Sw 1 (Rx). Does this change to the Rx1 port or does it >> remain on the Tx/Rx0 port? >> >> Rob >> _______________________________________________ >> USRP-users mailing list -- [email protected] >> To unsubscribe send an email to [email protected] >> > _______________________________________________ > USRP-users mailing list -- [email protected] > To unsubscribe send an email to [email protected] >
_______________________________________________ USRP-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
